Nature Unbound III – Holocene climate variability (Part B)

by Javier

The Neoglacial has been a period of progressive cooling, increasing aridity, and advancing glaciers, culminating in the Little Ice Age. The main Holocene climatic cycle of ~ 2400 years delimits periods of more stable climatic conditions which were identified over a century ago. The stable periods are punctuated by abrupt changes.

Previous post:  Part A

The Neoglacial period

Neoglaciation was the term coined to describe the global glacier advances after the Holocene Climatic Optimum (HCO) that François Matthes identified in the 1940’s. Glacier growth was caused by orbital-driven insolation changes. Although variability in local conditions caused the Neoglacial to start at different times in different glaciological areas, it is generally agreed that it started between 6000-5000 years BP in both hemispheres. Glaciers fluctuated with major glacier advances followed by shorter glacier retreats, culminating in the Little Ice Age when globally glaciers reached their maximum Holocene extent (figure 43). The Neoglaciation featured global cooling as temperatures responded more to the decrease in solar forcing due to orbital insolation changes than to the increase in GHG forcing.

Figure 43. Global glacier advances during the Holocene. Number of areas that display glacier advances for every century during the Holocene. World glaciers were distributed between 17 geographical areas. 12 belonging to the Northern Hemisphere are represented in brown, 4 from the Southern Hemisphere in blue, and one for the Low Latitudes in yellow. For a geographical representation of the glaciers included in each area see Solomina et al., 2015, figure 1. Orange and grey downward bars represent significant volcanic and cold events respectively according to the references indicated. Grey curve is the June insolation at 60°N (inverted scale). The Neoglacial period is characterized by generalized glacier advances that take place coinciding with the decrease in Northern Hemisphere solar forcing. Source: Courtesy of Olga Solomina.

Cooling events during the HCO, like the 8.2 kyr event, were followed by a complete recovery of temperatures and globally glaciers reached their minimum Holocene extent in most areas between 6000-5500 years BP. However there is evidence that the world did not completely recover from the cooling events that took place between 5600 and 5100 BP, initiating the Neoglaciation. This Mid-Holocene climate reversal has been recorded globally in multiple proxies both as a decrease in temperatures and as hydrological changes (Magny & Haas, 2004; Thompson et al., 2006). While the entire sixth millennium BP had a very challenging climate compared to previous millennia, the cooling event that took place 5.2 kyr BP was particularly abrupt (figure 44, Thompson et al., 2006). Due to the contemporary change of climate regime and global temperatures, some regions became cooler and drier, while others became cooler and wetter, leading to a rapid global glacier advance that buried organic remains, like the Quelccaya Glacier plant (Distichia muscoides, Peru), the South-Cascade Glacier rooted tree-trunk (Washington State) and the Ötztal Alps ice-man, that have remained continuously frozen until the present global warming (Thompson et al., 2006).

Figure 44. Evidence for an abrupt global cold and arid event at 5.2 kyr BP. High and low latitude locations of proxy evidence for abrupt climate change ~ 5,200 yr ago. Evidence for abrupt cooling (blue), aridity (red), flooding (green) and high wind (purple). South-Cascade Glacier rooted tree-trunk (Washington State); remains and artifacts in the Little Salt Spring (Florida); Cariaco Basin metal concentration (Fe, Ti) in ODP site 1002; Quelccaya Glacier ice-buried wetland plant Distichia muscoides (Juncaceae), dated at 5,138 ± 45 yr B.P.; bog pollen records of rapid and drastic vegetation changes in Isla Santa Inés (Chile); eolian soil record from Hólmsá (Iceland); North Atlantic benthic core in ODP site 980; dendrochronological records from Irish and Lancashire oaks with some of their narrowest rings during the 3,195 BC decade; Ötzi, the ice-man from South-Tyrol; core S53 palynological record from Burullus Lagoon (Nile Delta); Soreq Cave (Israel) speleothem; Mauritanian coast core 658C; Kilimanjaro ice-core record; Awafi dry lake sediments in SE Arabia; Lake Mirabad sediment in the Zagros Mountains (Iran); Lunkaransar dry lake sediments in NW India; sedimentary section along the Hongshui River, in the southern Tengger Desert, NW China. From multiple sources, some referenced in L.G. Thompson et al. 2006. PNAS 103, 10536–10543.

Coincident with the abrupt cooling and hydrological changes of ~ 5,200 yr BP, archaeological studies support a general pattern of abandoned Neolithic human settlements in several areas, including the Andes and the entire Eastern Mediterranean, indicating a widespread climatic crisis that marks the transition from the Chalcolithic to the early Bronze Age (Weninger et al., 2009).

Holocene climate variability

The Last Glacial Maximum and the HCO constitute two extreme metastable states, separated by only 10,000 years, that correspond to essentially the same amount of incoming energy from the Sun. The main difference between both states is in the redistribution and minimal or maximal exploitation of that energy by the planet. This is due to the orbital configuration, tectonic disposition, ice and cloud albedo, oceanic-atmosphere response and biological feedback. Since they constitute dramatically different climatic states, the nature of abrupt climatic changes is also different in the two states. Glacial variability comes mainly in the form of warming episodes (Dansgaard-Oeschger events; figure 45) while interglacial variability comes from cooling episodes (Bond events; figure 45). There are no global warming abrupt changes in the Holocene once the thermal maximum is reached, just cooling events followed by recovery.

The other major salient characteristic of the Holocene abrupt climatic changes compared to glacial abrupt changes is their much smaller amplitude (figure 45). It has become a lot more difficult to identify these changes because their signal is much lower and more difficult to separate from the noise of small high frequency climatic variability. This has created much confusion about the nature and causes of Holocene abrupt climatic changes and has given many the false impression that the Holocene is characterized by long periods of climate stability. Nothing is further from the truth. The Holocene is a period of almost constant climate change with climatic stability being the exception.

Figure 45. Nature of climatic oscillations during the Ice Age. Oscillations during an interglacial are smaller and are cooler (Bond) events, and oscillations become larger the colder temperatures become. During the glacial period oscillations are very large and are of a warming nature (Dansgaard-Oeschger events). The black line represents the obliquity cycle. The asterisk marks the current position, where we are very worried that the present warming is the ‘largest in thousands of years’ instead of being worried that the next cooling will also be bigger than the previous and will probably lead to glacial inception.

In 1968 climatologist J. Roger Bray recognized several major past cooling episodes and attributed them to a solar cycle. “A combination of geophysical, biological and glaciological information supports the idea of a 2,600 year solar cycle” (J.R. Bray. 1968. Glaciation and Solar Activity since the Fifth Century BC and the Solar Cycle. Nature 220, 672-674). This solar cycle, slightly shorter than he calculated, is now known as the Hallstatt cycle while, in justice, it should be named the Bray cycle. Since Bray’s report, other researchers have confirmed the reoccurrence of cooler climates with a periodicity of about 2400 – 2600 years by different techniques, glacial moraines, temperature-sensitive tree rings widths, and δ18O isotope and chemical analysis of sea salts and dust in ice cores (O’Brien et al., 1995). Most researchers also ascribe a solar origin to this climatic cycle, since the cooling periods coincide with periods of high Δ14C formation, which is associated with low solar activity.

By looking at proxy temperature reconstructions and at major global glacier advances, and other climate proxies, it is easy to recognize the major abrupt cooling changes of the Holocene. Roger Bray identified cooling episodes at 0.3, 2.8, 5.5, 8.2 and 10.2 kyr BP over 45 years ago (figure 46). These episodes give us an average spacing of ~ 2400 years and, at the same time, they define the major climatic states of the Holocene.

Figure 46. Northern Hemisphere paleoclimate records showing main Holocene abrupt climate change events. (A) Greenland GISP2 ice-core δ18O. (B) Western Mediterranean (Iberian Margin) core MD95-2043, sea surface temperature (SST) C37 alkenones. (C) Eastern Mediterranean core LC21 (SST) fauna. (D) North Atlantic Bond series of drift-ice stacked petrologic tracers. (E) Romania (Steregoiu), mean annual temperature of the coldest month. (F) Gaussian smoothed (200 yr) GISP2 potassium (non-sea salt) ion proxy for the Siberian High pressure system. (G) High resolution GISP2 potassium (non-sea salt). Notice that all Holocene abrupt climate changes are cooling events. Source: B. Weninger et al. 2009. Documenta Praehistorica Vol. 36, pp. 7-59.

The Bray cycle delimits five periods that roughly correspond to the Blytt-Sernander sequence. Vegetation changes suggest that they constitute distinctive climatic states established by insolation conditions from the obliquity and precession cycles (figure 47). Every abrupt cooling from the Bray cycle would constitute a tipping point in the gradual insolation changes and the world would settle to a different climatic state after recovering. We have just started a sixth period with the proposed name of Anthropocene, that should last around 2,200 years, until about 4,200 C.E. Every one of the last five periods (since 10.2 kyr ago) started with global warming as a recovery from the depressed temperatures of the cooling oscillations that separate the periods.

Figure 47. Major periods of the Holocene set by obliquity and a ~2400 year Bray cycle. Black curve, global temperature reconstruction by Marcott et al., 2013, from 73 proxies averaged by differencing and with the original published dates. Temperature anomaly rescaled as in figure 37. Purple curve, Earth’s axis obliquity cycle. Blue boxes, major periods of regional and global glacier advances as in Mayewski et al., 2004 and references within. Red curve, Bond et al., 2001 ice-rafted debris stack (inverted) from four North Atlantic sediment cores. Grey bars, cooling oscillations part of the ~2400 year Bray cycle. Pink bars, the 8.2 kyr cooling event proposed to be due to the outburst of pro-glacial Lake Agassiz and the 4.2 kyr arid-cold event. Grey arches on top, a regular 2475 year periodic marker.

Bond events

In addition to the major cooling events of the Bray cycle, other cooling events have taken place during the Holocene, and they have been seen in numerous proxies, but particularly in the Bond series of events. The amount of detrital petrological tracers transported by icebergs and deposited in the ice-rafted debris belt (an Atlantic region between 40-50° N) greatly increases during episodes of southward and eastward advection of cold surface waters and drift ice from the Nordic and Labrador seas (Bond et al., 2001; figure 48 A). This sensitive proxy has registered every cold episode of the Holocene, with a resolution of 50 years.

Figure 48. Bond events constitute a record of cold events during the Holocene. (A) Map of North Atlantic coring sites. Bond events represent periods of increased deposition of petrological tracers by drift ice at the core locations (black dots) within the ice-rafted debris belt (IRD, yellow box). They are interpreted as periods of cooler, ice-bearing surface waters displaced eastward from the Labrador Sea and southward from the Nordic Seas. (B) The Holocene record of iceberg activity (black curve) is a stack of the four cores showing the combined detrended record of hematite-stained grains, detrital carbonate, and Icelandic volcanic glass. The last drift-ice period corresponds to the Little Ice Age, and other known climatic periods of the past can be correlated to this record. The numbering of enhanced drift-ice periods represents the unsuccessful attempt by Gerard Bond to correlate the now called Bond events with the ~ 1500 year Dansgaard-Oeschger stadial cycle, also reflected in ice-rafted debris records. Source: G. Bond et al., 2001 Science 294, 2130-2136. The Bond cycle is a composite of different periodicities. The early Holocene period clearly displays 1,000 year periodicity as shown by a Gaussian filter applied on the series (green curve). A 1,500 year periodicity is only present from 6,000 yr BP (red curve). The 1,500 year fit is problematic as some peaks appear to follow the 1,000 year periodicity. Source: M. Debret et al., 2007. Clim. Past Discuss., 3, 679–692.

Gerard Bond attempted to fit the periods of increased drift-ice that he identified during the Holocene into a single cycle related to the Dansgaard-Oeschger cycle, by making two unwarranted assumptions: That every period of cooling responded to the same cause, and that some well-resolved peaks separated by several centuries to a millennium could correspond to a single cold event. The evidence, however, shows that the HCO displays a millennial periodicity in Bond events, with single isolated peaks separated by ~ 1000 years, while the Neoglacial shows a more complex picture with multiple peaks not so well resolved and a more irregular spacing. Debret et al. (2007), adjust the Bond record of Holocene cold events to a 1,000 year periodicity between 12 and 7 kyr BP and to a 1,500 year periodicity for the last 6,000 years (figure 48 B). It is clear that the Bond record mixed periodicity reflects the climatic shift that took place at the MHT from mainly solar forcing to a mixed solar and oceanic forcing (figure 41), and therefore it can be concluded that the first assumption of Gerard Bond is incorrect: different peaks represent cooling from different causes, and thus a Bond cycle does not exist in the Holocene. We must reject also his second assumption and treat every peak as a different cooling event and try to identify the cause that originated it. We must move from a Bond series of 8 events (plus number zero) in 12,000 years (one event every 1500 years), to a series of at least 15 cold events with a mixture of periodicities during the Holocene.

The lows of the ~ 2400 year Bray cycle, the main climatic cycle during the Holocene, correspond to Bond events 7, 5a, 4a, 2a, and 0. These events not only show a corresponding age and correct periodicity, but they also constitute the highest petrological tracer peaks for each 2400 year period, suggesting that they were the strongest cooling periods at each time, as glaciological, biological and geophysical evidence also supports.

Holocene millennial cycles

As we have seen in part I and II of the series, low frequency-high amplitude climate change does not take place in a chaotic manner, but mainly through cycles, quasicycles, and oscillations that respond to periodic changes in the forcings that act over the climate system. Figure 49 (adapted from Maslin et al., 2001) shows that these climatic periodicities cover the full spectrum of climate variation, and that, in general, the longer periodicities produce larger variations in climate. Thus Holocene climate change is dominated by periodic variability in the millennial band (grey band, figure 49).

Figure 49. Climate cycles and periodicities dominate climate change at all temporal scales. Spectrum of climate variance showing the better studied climatic cycles and their proposed forcings, although some are not widely accepted. Cycles, quasicycles, and periodic oscillations are found over the entire temporal range, indicating they are a salient property of climatic variability. As a general rule, the lower the frequency, the more intense the climatic variance produced. The 150 Myr Ice Age cycle has produced four Ice Ages in the last 450 million years. It is proposed to be caused by the crossing of the galactic arms by the Solar system. The 32 Myr cycle has produced two cycles during the Cenozoic era, the first ending in the glaciation of Antarctica and the second in the current Quaternary Ice Age. It is proposed to be caused by the vertical displacement of the Solar system with respect to the galactic plane. The orbital or Milankovitch cycles are the best studied, and between them and the Lunar nodal regression cycle of 18.6 years lies the orbital gap, where no astronomical cycle is known to affect climate. Our knowledge of this range is very insufficient, despite millennial climate cycles (grey band) determining most of Holocene climatic variability. Short term climate variability is dominated by the El Niño-Southern Oscillation. Adapted from: M. Maslin, et al. 2001. Geophysical Monograph Series 126. pp. 9-52.

Within the paleo-climatological scientific community there is widespread acceptance of millennial cycles during the Holocene because their effects are observed in most climatic proxies, and there is ample agreement over certain periodicities that come out of frequency analysis and are in phase from multiple proxies at different locations. Instrumental-era climatologists and astrophysicists are however very skeptical of such periodicities because they have not collected evidence about these long cycles in the short time of modern instrument observations, and we lack a proper understanding of the mechanisms that generate the periodicity and produce the climatic effect. Similar objections were made to Alfred Wegener’s continental drift theory that despite solid evidence from geography, geology, paleontology, and biology, was shunned until the development of plate tectonics theory could explain how continents drifted.

A further complication arises because some climate periodicities do not show the behavior of proper cycles and present gaps when the signal cannot be detected in the data. We already observed that problem when reviewing the Dansgaard-Oeschger cycle, where the oscillations depend on a set of conditions in sea-level, temperatures, and obliquity, to become perceptible. Wavelet analysis of millennial climate cycles during the Holocene shows periods when one or more of the currently operable cycles do not show up in the data. As we do not have a proper knowledge of the mechanisms of these cycles, we do not have an explanation for this behavior. And we also have to consider the awkward nature of most climate proxy data (Witt & Schumann, 2005), which is affected by random and systemic errors causing uncertainties along the age axis that grow worse as we go back in time. This data is often unevenly sampled and has increasing compression with growing age, causing a reduction in data density in the older portion of the data. It also suffers from different noise intensity for different paleoclimatic periods and is affected by changing sampling rates. Quite often this awkward nature of paleoclimatic proxy data is not properly accounted for when performing standard time series analyses, which were developed for evenly sampled and stationary time series over a well-defined time axis.

Despite these problems, three relatively well established millennial-scale climatic periodicities can be described based on evidence. They are the already mentioned ~ 2400 year Bray solar variability cycle, a ~ 1500 year oceanic cycle that might be related to the D-O cycle of glacial periods, and the ~ 1000 year Eddy solar variability cycle. As mentioned above, Holocene cycles display abrupt cooling at their lows, creating the conditions for enhanced iceberg activity in the North Atlantic that produces Bond ice-rafting events. As the three cycles have different periodicities, sometimes the lows of two cycles are so close together in time as to make it difficult to resolve them. This is the case in the Little Ice Age, when the lows of all three cycles took place in close succession, contributing to make this the coldest period in the Holocene, bringing it to the brink of triggering a glacial period. After each abrupt cooling of the lows of these three cycles comes a warming recovery, that was a complete recovery during the HCO, but only partially complete during the Neoglacial. The global warming that has taken place during the last 350 years cannot be separated from the previous cooling without losing part of its context. As already indicated in figure 46, each period of warming during the descent to the next glacial stage should be more intense than the previous ones, as climatic variability increases outside the warm conditions of an interglacial climatic optimum.

Conclusions

6) The Neoglacial has been a period of progressive cooling, increasing aridity, and advancing glaciers, delimited by the 5.2 kyr event at its beginning and the Little Ice Age at its end.

7) Holocene climate variability is characterized by periodic cooling events of reduced amplitude compared to glacial climate variability. The main climatic cycle of ~ 2400 years delimits five periods of consistent climatic conditions identified over a century ago in the Blytt-Sernander sequence, separated by abrupt climatic changes.

8) Additional Holocene abrupt climatic variability is reflected in Bond peaks of increased drift ice in the North Atlantic. Abrupt Holocene variability responds mainly to periodicities in the millennial time frame. Abrupt Holocene changes have all been of a cooling nature, followed by global warming.

9) Bond events display a mixture of periodicities that respond to different forcings, thus a Bond cycle does not exist in the Holocene.

Acknowledgements

I thank Andy May for reading the manuscript and improving its English.

References [bibliography  ]

Moderation note:  As with all guest posts, please keep your comments civil and relevant.

314 responses to “Nature Unbound III – Holocene climate variability (Part B)

  1. Good to know (and not surprising) that the climate is not naturally unchanging. Need to tell NSF this, see my https://www.cato.org/blog/nsf-climate-denial. Is there any other relevance of this post to the present situation? You mention the little ice age as an end point, but do not discuss this that I can see. Did it end naturally?

  2. Thank you Javier. You have advanced my understanding of Holocene climate considerably. Previously I only thought in terms of Minoan, Roman and Middle Ages warm events.

    • That’s exactly my goal, Mike. To increase people’s knowledge of paleoclimatology. It is surprising how even climate scientists are writing articles about past climate without having done enough reading of the scientific literature on the subject.

  3. Hi David,

    Taking the present situation out of its context is likely to lead to a misunderstanding of what is happening.

    So far the LIA is the end of the cooling. This says nothing about the future. The end of the LIA was obviously natural. Solar activity recovered and volcanic activity diminished. This allowed a natural rebound of the climate to warmer conditions. What on a millennial scale looks like a progressive cooling, on a centennial scale is characterized by more abrupt cooling and posterior warming. Our point of view is just too shortsighted for these processes.

    Present and future climate change will be dealt with in the last article of the series. As they are, the articles are already so long that they need to be split in two.

    • Javier thank you very much.You work hard at your craft. I will enjoy reading these posts twice. You answer questions with knowledge, patience and scientifically. Very impressed!

  4. Pingback: Nature Unbound III – Holocene climate variability (Part B) – Enjeux énergies et environnement

  5. There is a hint of something important happening at the end of this period that needs to be addressed for a complete treatment of this subject.

    I know some don’t regard the last century of warming as significantly outside of the millennial variation, but there is an argument that it is when you look at it.

    • Jim D:

      If a spike (for want of a better name) of the type demonstrated by the HadCRU trace (red) had occurred 2,000 or 4,000 years ago would the Marcot reconstruction have caught and displayed it? Put another way, does Marcot’s method have sufficient bandwidth to catch such rapid changes?

      And … why is the shaded area so much wider beginning 500 years or so ago?

      • That’s why I called it only a hint. There is a school of thought that this is the beginning of a rise of several degrees that could last centuries, which would put other millennial fluctuations into a different context when you visualize that on this graph.

    • The post 1950 warming will be dealt with in due term.

      But I can tell you that figure is deceiving. Instrumental temperatures don’t extend prior to 1850 except for CET, which doesn’t show such prominent spike, and neither do proxies that extend to the present, so with that mix you have built yourself a deception, and you know it.

      We are quite sure that at the Holocene Climatic Optimum globally glaciers were more reduced than now and there was much less sea ice in the Arctic. That figure is bogus.

      • The last part is thermometer based, so it is the most certain part. I know skeptics don’t accept this part of the graph. The HCO, while interesting, is peanuts compared to projected temperatures, even if you average them through the 21st century, or whatever averaging period you want to compare with Marcott. The theory for AGW is better founded in observations and physics than Milankovitch’s, so I find it interesting that skeptics accept the latter scientific consensus, and not the former, despite it being the same scientists who accept and develop both. The scientific community has no such dichotomy.

      • The last part is thermometer based, so it is the most certain part.

        Precisely. You cannot compare temperatures measured by thermometers to temperatures estimated from proxies.

        The HCO, while interesting, is peanuts compared to projected temperatures

        The HCO is real. Projected temperatures are fantasy. You can always make fantasy much bigger than reality.

        The scientific community has no such dichotomy.

        I am part of the scientific community.

      • You seem to believe the proxy part more than the thermometer part and therefore Milankovitch more than AGW. Have you figured out your basis for making these distinctions? Radiative physics says doubling CO2 adds a lot more forcing to polar latitudes than the Milankovitch effect, but you demur on accepting that it is also important for the sea-ice and glacier balance and possibly that higher CO2 levels near 500 ppm could prevent the next Ice Age. There is a book by David Archer called The Long Thaw that brings these two concepts of CO2 and Milankovitch cycles together. I recommend you to also find a way to combine these to make your work more relevant to what is actually happening today. How much carbon needs to be burned to prevent the next Ice Age is an interesting question that he addresses, and there is enough paleo-evidence to get a good estimate.

      • Except for the last few years, proxy evidence is all we have to try to know the past climate of the earth. Thermometers are useless for that.
        David Archer is wrong. He doesn’t understand glaciations, as he uses 65°N summer insolation, when glaciations clearly respond to obliquity, as we saw in the first article of the series.
        https://judithcurry.com/2016/10/24/nature-unbound-i-the-glacial-cycle/

      • Then your view, contrary to David Archer and paleoclimate science in general, is that lots of CO2 can’t prevent an Ice Age, or how much do you think it takes? How do explain the absence of Ice Ages for most of the last 100 million years? I don’t think you have thought this aspect through much because you have avoided that critical topic of why Ice Ages now and not before. There were no Ice Ages until CO2 levels dropped into the 300 ppm range. What is your preferred, and it better be published, explanation for that?

      • Then your view, contrary to David Archer and paleoclimate science in general, is that lots of CO2 can’t prevent an Ice Age

        It cannot be argued that paleoclimate science in general has a unique view on this matter. Some authors like Archer and André Berger believe that a glaciation is not possible under present circumstances, but if their assumptions are wrong, they are wrong. They are not based on evidence as glaciations have not failed to take place under falling obliquity for millions of years.

        How do explain the absence of Ice Ages for most of the last 100 million years?

        No explanation is needed. Periods of ~ 100 Myr between ice ages are the default situation regardless of what CO2 does. Ice ages present an apparent periodicity that CO2 does not.

        There were no Ice Ages until CO2 levels dropped into the 300 ppm range. What is your preferred, and it better be published, explanation for that?

        How do you rule out the opposite explanation, that CO2 levels dropped because there was an ice age?
        How do you explain past periodicities in temperatures? How do you explain this for example:

        Original figure from Bill Illis.

      • You have some very odd views. I’ll leave it at that. Does anyone else share these opinions of yours? CO2 levels are mostly governed by plate tectonics, geological cycles, where volcanoes emit it and weathering reduces it. To no one’s surprise periods of high CO2 such as the mid-Eocene 50 million years ago were iceless hothouse conditions, while the decline in the last 50 million years has corresponded to a slow cooling until now, and being the lowest CO2 level in the last 100 million years,this corresponds to the only period with Ice Ages that dominate the last 2 million years.

      • Well, you can try for example Nick Eyles.
        Eyles, N. (2008). Glacio-epochs and the supercontinent cycle after∼ 3.0 Ga: tectonic boundary conditions for glaciation. Palaeogeography, Palaeoclimatology, Palaeoecology, 258(1), 89-129.
        http://www.brynmawr.edu/geology/documents/Eyles2008Palaeo.pdf

        “some authors propose a 10 Ma long North African glaciation that started much earlier in the Ordovician (Ghienne, 2003) and lasted well into the Silurian (Grahn and Caputo, 1992; Caputo, 1998; Pope and Read, 1998; Crowell, 1999; Saltzman and Young, 2005). The last (and thus best known) Late Ordovician Saharan ice sheet formed during a time of high (16 × the modern value) atmospheric CO2 (Torsvik and Cocks, 2004; Fig. 2E). The ice sheet may have been comparable in size to the last North American Laurentide Ice Sheet (∼36×106 km3) and expanded eastward from North Africa onto the Arabian platform.”

        Do you get that? An ice age with 16x modern CO2 values. Things don’t appear to be as you tell.

      • The Ordovician ice can be explained using one extra fact known from the evolution of such stars in astrophysics, that the sun is now 4% stronger than it was then. 4% nicely works out to be equivalent to 16xCO2. SkS addressed this one already, but it does keep coming up. This neatly puts it in perspective.

      • Crowley, T. J., & Baum, S. K. (1995). Reconciling Late Ordovician (440 Ma) glaciation with very high (14X) CO2 levels. Journal of Geophysical Research: Atmospheres, 100(D1), 1093-1101.
        http://onlinelibrary.wiley.com/doi/10.1029/94JD02521/full
        “The most dramatic exception to this correlation involves the Late Ordovician (440 Ma) glaciation, which occurred at a time when CO2 levels may have been much greater than present (14–16X?). Since decreased solar luminosity at that time only partially offset increased radiative forcing from CO2, some other factor needs to be considered to explain the glaciation.”

        Sorry, wrong answer, but you get to participate again.

        The Late Ordovician is like the Pause. Plenty of different, often incompatible, explanations for evidence that doesn’t fit the hypothesis.

      • You express a lot of certainty about the CO2 level which is not warranted that far back in time. Just in terms of relative forcing, 4% less solar, which is also an estimate, balances 16xCO2 in the physics that you seem to want to deny. This turns it into far less of a mystery than you want it to be. It is well within the error bars that the data have. Better to look at the Eocene where CO2 and temperatures are known better, and sea-levels and continental configurations.

      • When you don’t like the data you question it. When you like it you accept it like revealed truth.
        The uncertainty is a doubled edged sword. If you can’t be sure about CO2-temp relation in Late Ordovician, you can’t be sure either at any other past ice age. So you don’t score.

        Now let’s see what Horton says about Late Paleozoic Ice age:
        “In our simulations, ice sheets appear at atmospheric pCO2 concentrations between 420 and 840 ppmv.”
        Horton, D. E., Poulsen, C. J., & Pollard, D. (2010). Influence of high-latitude vegetation feedbacks on late Palaeozoic glacial cycles. Nature Geoscience, 3(8), 572-577.
        http://www.nature.com/ngeo/journal/v3/n8/full/ngeo922.html

        Last time I checked we were at 415 ppm. So it appears other authors defend ice ages are possible with double amount of CO2.

        Lots of scientific opposition to Archer ideas.

      • You can be much more sure of the recent Ice Ages than the Ordovician, and also the Eocene is better known. Your argument about the foggy past uncertainty in data does not have relevance to what we can measure accurately today. How about a billion years ago? We don’t know much about that CO2 level or temperature either? Does that forward your argument any? From the Eocene we can see geological effects on time scales of 10 million years, a resolution we don’t even have for the Ordovician.
        Now you want to talk about a modeling study. Tell me why you believe it? Models failed to predict the loss of sea ice we have seen. This seems to indicate that their sea ice is too insensitive to changes. Sea ice is a particularly difficult area for them as it is also tied in with ocean currents.

      • Much more sure is still very unsure. I just linked an article that shows we do not know what was going on with the carbon cycle at the Eocene 50 Myr ago.

        You have your favorite explanation. Fine. Your insistence in it being the right one when you don’t have the evidence to demonstrate it is bothersome. Alternative explanations exist in the literature and they are vigorously defended, as I have shown.

        As Matthew Saltzmann says:
        “The cause of the late Paleozoic (ca. 355–255 Ma) ice age remains uncertain. A lowering
        of atmospheric carbon dioxide levels near the beginning of this time period occurred in response to the rise of land plants and likely cooled Earth, but the rapid growth of extensive Gondwanan ice sheets was delayed for tens of millions of years, until the Late Mississippian.”

        Saltzman, Matthew R. “Late Paleozoic ice age: Oceanic gateway or pCO2?.” Geology 31.2 (2003): 151-154.
        http://u.osu.edu/saltzman.11/files/2014/05/Geology_2003_Carbonif-1l0g927.pdf

        So stop pretending that science agrees with you. Some scientists do and some don’t.

      • You can read that article and they have the same expectation of high temperatures with high CO2 levels as me. You can try to find someone that didn’t expect the mid-Eocene to be so warm, or who explains it a different way to make an actual argument here, but n one has been forthcoming.

      • Nothing wrong with the Eocene. Doesn’t need any more explaining that any other bump in this Phanerozoic graph.

      • Giving a whole new meaning to post hoc ergo propter hoc.

      • “You can always make fantasy much bigger than reality.” (Javier, above)

        An elegant summation of the present situation.

      • Jim D:
        “How do explain the absence of Ice Ages for most of the last 100 million years?”
        Continental drift setting up ocean circulations.

      • The Ice Ages started within the last 2 million years. What aspect of continental drift do you think happened in such a short period? Why not that CO2 levels only became 300 ppm or less in this period, lower than at any time in the last 100 million years. Did you discount that as a factor? Can you have Ice Ages at 500-700 ppm by any theory that you can imagine?

      • Can you have Ice Ages at 500-700 ppm by any theory that you can imagine?

        Late Ordovician Ice Age is believed to have taken place at >5000 ppm with a huge ice-sheet over the Sahara. Your theory must be wrong.

      • The sun was weaker, see above.

      • The sun was weaker, see above.

        Sorry, that doesn’t explain it unless you reduce a lot CO2 climate sensitivity. That is the problem of setting it so high. See above.

      • It’s not sensitivity, it is forcing. There is a difference. The forcing change by reducing the sun 4% and by increasing CO2 16 times is about 15 W/m2. The energy may be redistributed, but the net is the same.

      • You say they match. The Crowley paper referenced above says they don’t. I’ll go with the published scientific article.

      • You can read your 1995 paper and find that they can get snow cover under reduced solar forcing, so I am not sure what point you want to make with it, but it is good that you support it. Progress. Yes, the solar difference was important in the Ordovician. Move on.

      • you seem to conveniently forget the main point:

        “some other factor needs to be considered to explain the glaciation.”

      • yes, elevation.

      • Or not.

      • OK, so now you disagree with the paper you promoted. Fine.

      • I have noticed you have problems to understand. Scientists do not agree on the explanations for the Late Ordovician glaciation, as they do not agree on the causes of the Pause. That is my point.

      • You have not yet even acknowledged that the large 4% change in solar intensity since then is equivalent to 16xCO2. I think it is you that is having trouble understanding this rather important factor.

      • We go back to the same issue. Why should I acknowledge something that is a proposition and has not been demonstrated?

        The effect of CO2 on climate and temperatures is largely unknown, as for 38 years we have not advanced in constraining the uncertainty of its climate sensitivity. Therefore its forcing is “assumed.” Nobody knows. Then how could we possibly acknowledge that it exactly matches the long term change in solar intensity? It is proposed to match it so we can give an explanation to the apparent homeostasis of temperatures. But that explanation might very well be incorrect.

        I am very suspicious of explanations that require that two independent processes (sun’s star sequence evolution and earth’s CO2 evolution) neatly match each other for billions of years.

        To me the mot likely explanation is that water regulates temperatures on earth through its amazing properties, and CO2 just goes along for the ride having a lot less effect on temperatures that is currently assumed.

      • The forcing from CO2 is not assumed. It is calculated from physics. If you even dispute the 3.7 W/m2 per doubling, I can see how you cannot equate irs effect to solar changes, and that is an extreme view far beyond Lewis, Curry, Lindzen. Spencer and even Monckton, who all accept the forcing part. In reality we can equate the forcings. Doubling CO2 is about the same effect as increasing solar intensity by 1%. You don’t want to believe it. I can’t help you.

      • And you forget the fine print: “all other things being equal.” And they never are. Changes in the opacity of the atmosphere or the lapse rate make those calculations invalid. Not to speak of changes in water vapor. If you want to believe that you can equal past solar intensity to past CO2 levels, keep dreaming.

      • If you want to argue about the quantitative forcing effect, take it up with Judith. This is a basic assumption in papers by the A-list skeptics I have listed, and puts you in a skeptical B list that doesn’t even rise to their level. If you deny that CO2 has any effect at all on even the forcing, let alone the temperature, that would be the C list. So far, I have not gathered enough information from you to see if you believe in any CO2 effect at all on the forcing.

      • Jim, my thoughts are that the deepening of the Antarctic ocean allowing a circumnavigation of waters, the closure of the Panama opening, the cool waters going up Atlantic way increasing productivity and blooms of krill evidenced by whales to get to their massive size in the last two million years. The mixing of cool and warm waters allowed increase in productivity and a drawdown of carbon. Why the sudden changes to interglacial periods? Not sure, working on a hypothesis of ice linking South America interrupting the flow forcing bottom waters to come to the surface releasing sequestered carbon. BTW, the Antarctic glaciers were forming at 800 ppm. What would it take to prevent the next glaciation event? My guess 500 ppm maybe 550. We have about 50-70 years until that happens. How much carbon resources do we have? We have rejuvenated the earth for a bit accidentally. I think we will be fine, we have time to figure things out.

      • From CO2 estimate like this, we don’t see that Antarctic glaciation 35 million years ago could have occurred at much more than 800 ppm, and the much higher CO2 levels before that were even favorable for forests at polar latitudes. Forests expand in high-CO2 conditions and replace tundra in the Arctic areas. Glaciation has no chance in those conditions, and it is because of the CO2. For Greenland the Arctic sea-ice the threshold may be nearer 400 ppm.
        http://environmentcounts.org/dl525?display&x=700&y=446

      • From CO2 estimate like this, we don’t see that Antarctic glaciation 35 million years ago could have occurred at much more than 800 ppm, and the much higher CO2 levels before that were even favorable for forests at polar latitudes. Forests expand in high-CO2 conditions and replace tundra in the Arctic areas. Glaciation has no chance in those conditions, and it is because of the CO2. For Greenland the Arctic sea-ice the threshold may be nearer 400 ppm.

        Sounds like you are reciting a creed. In reality if in the near future we find out CO2 climate sensitivity is low we will have absolutely no problem in changing the hypothesis and will still be able to explain everything. We have a very high capacity to explain things, not so high to get the correct explanation.

      • Reciting what is observed in the last 100 million years. High CO2 no ice, Low CO2 ice. Also a relation to sea level.

      • High CO2 no ice, Low CO2 ice.

        You can also say it backwards. No ice high CO2, Ice low CO2.
        That you can write it one way doesn’t mean that you have the correct cause-effect relation.

      • CO2 changes by about 10-15 ppm per degree C from outgassing, as we see since the last Ice Age, and it is largely the ocean chemistry that explains this magnitude. No one is surprised that CO2 went up from 190 ppm to 280 ppm with warming and no other emissions. In the Eocene, variations are ~1000 ppm, which would either take a heck of a temperature swing or geological processes. The scientists go with geological processes because the long-term carbon cycle is understood. These types of things I say seem to come as a complete surprise to you, but you can read about them in textbooks.

      • the long-term carbon cycle is understood.

        We wish. Here is an example of how little we understand the long-term carbon cycle:

        Sluijs, Appy, et al. “A middle Eocene carbon cycle conundrum.” Nature Geoscience 6.6 (2013): 429-434.

        In science almost everything from the past is up for discussion and everything about the future is speculation. You don’t get this because you are not a scientist and you don’t see the coming and going of hypotheses with new evidence all the time.

      • OK, what do they refute that I have said? They explain high temperatures with high GHG levels, which you apparently don’t. Is every detail known? No. Do we know more about it than the Ordovician? Yes.

      • Read the paper. Our knowledge of the carbon cycle does not explain the evidence.

        They refute that we understand the long-term carbon cycle. Clearly we don’t.

      • They just had to account for elevation. Did you read past the beginning into what they did?

      • Of course they had to add some other explanation. That was the main goal of the paper. But I have several articles each one with a different explanation, so the point is not that they found one, but that the glaciation at 16X CO2 levels cannot be explained solely as a function of a fainter sun as you claim.

        So we are back at square one. The hypothesis cannot explain Late Ordovician glaciation. Of course we can find alternative explanations, but are they true? Probably not.

      • The fainter sun is still 90% of the explanation whether you like it or not. Maybe you recognized its importance some way back in this argument, but there it is. When skeptics have to go back into the foggy past 450 million years ago to make an uncertainty argument, you know they’re just avoiding the more recent and certain data which they still have trouble with, and this ploy does not remove.

      • You like to talk about things we don’t know as if they were a certainty, while criticising others for raising doubts. The Phanerozoic paleo data can support one thing and the opposite. That’s the reality whether you like it or not. The fundamental problem is not the Late Ordovician, but the disparity between CO2 levels and temperatures. Excepting the Carboniferous atmospheric crisis CO2 levels have been generally on the decrease, while temperatures have shown a cyclic behaviour.

        Temperatures are always oscillating within the narrow margins that allow life, and alternate greenhouse and icehouse conditions. Since the CO2 does not show alternation the hypothesis has a problem, and obviously the farther back the bigger the problem as CO2 has been on a down trend for hundreds of millions of years.

        The fainter sun hypothesis tries to save the CO2 hypothesis, but has a problem. The rate of increase in solar forcing is very slow, many hundreds of millions of years, while the rate of decrease of CO2 is very fast. From 10,000 ppm to 300 ppm in the same period.

        So the next attempt to salvage the CO2 hypothesis has been to change the temperature reconstruction (this is a classic) and try to give it a downward trend that matches better the CO2 downward trend. This aggravates the problem the farther back in time because it leaves the Late Ordovician with the temperatures of the Miocene optimum and higher CO2 levels making impossible an ice age.

        So what we have is the same story all the time. A hypothesis that doesn’t fit the evidence. Ad hoc explanations are built for the most egregious deviations, while the data is reinterpreted as much as needed to fit the hypothesis. And this is what you claim success.

        Once most scientists become convinced that CO2 cannot have that much effect on climate this is all going to be extremely easy to undo. We go back to the prior reconstructions and discard the ad hoc explanations and bingo, in one day we can explain the opposite.

      • Without allowing for the effect of changing GHGs, which we know already has a 33 K effect at today’s level very little of the geological link to climate change can be understood by you. Perhaps you think that just because CO2 varies by 1000 ppm due to tectonic plate movements it has no link to climate changes that occur with the GHG changes. Without knowing how you explain the warming by up to 10 C as CO2 rises in response to volcanic periods, it is hard to figure out your thinking, if any, on this issue. Perhaps these 10 C swings are a complete mystery to you rivalled only by what has happened to global temperatures in the last 100 years. That is what you are implying.

      • Jim D, I have tried to explain to you that scientists build hypotheses all the time to try to explain the evidence. But the fact that we can build a hypothesis doesn’t mean that:
        a) It is the right hypothesis
        b) we couldn’t easily build an alternative one

        Even with Royer’s doubtful corrections, the temperature on earth shows a very clear 150 Myr periodicity

        While CO2 despite we know it is both influenced by temperatures and influences temperatures, does not show that periodicity.

        The conclusion is clear. CO2 cannot be the primary driver of temperatures. All the rest is wiggling and introducing ad hoc explanations at different times to defend a failed hypothesis.

      • Hypotheses are built to explain things. In this case much of paleoclimate is explained by GHG changes driven by known geological processes as the continental plates move. Basically it explains the big picture of what has happened over the past billion years including icy phases in the Ordovician, Permian and now, and how the former two terminated, plus the last century of steady warming. If you want to replace the hypothesis you have to have a better explanation because throwing it out leaves you with mysteries like how the earth escaped any of its past Ice Ages, for which you would have no mechanism that fits the evidence, and how we had a degree of warming just at the same time as the CO2 rose by 40%, which is a demo of the hypothesis if you ever needed one.

      • Discarding a wrong hypothesis and not substituting it by another does not decrease knowledge. If a hypothesis is incorrect it is better to throw it out, because false knowledge is worse than knowing what is unknown.

      • This hypothesis explains things. Discarding it means you can’t explain it at all, or you have a better explanation. You are telling the scientists that you don’t understand it at the level they do and are somehow blaming them for your own failing.

      • Providing an explanation is not a goal for science. Providing the real explanation is. If a hypothesis is wrong it doesn’t matter that you don’t have another one.

        Scientists don’t understand sufficiently the climate or models would not perform so poorly.

      • The explanation covers the known facts. No one is surprised the 1 C of warming in the last century because what would be more unexpected given the basic physics of such a large forcing change would be no warming.

      • About 20 million years ago, the Americas joined in area of Panama. What is now the Suez canal also closed. Equatorital ocean currents could no longer more or less, circle the globe and they could circle the globe around Antarctica. Somewhat isolating Antarctica. Also about 85 million years ago, Australia broke away from Antarctica.
        The end of this illustrates:

        Your 2 million years, thermal mass I suppose. Since CO2 levels used to be so stable, I guess it needed to be put into the oceans while the atmosphere cooled, think of the ocean disruptions when continents meet and separate. Assume the Thermohaline circulation reversed. Do you think that might upwell some carbon somewhere? If it did, it would have end up back in the oceans perhaps slowing cooling. When do we expect equilbrium when continents meet or separate?

      • Your plot shows Antarctica glaciating with CO2 more or less stable at 500 ppm and then about 1/2 way through the ppm drops. They also decide to show continental drift.

      • Ragnaar, the drop in ppm possibly results from a sudden cooling that occurred about the time of the Antarctica glaciation. It is consistent with this cooling.

      • Steven Mosher

        More Science by Assertion

        Javier: ‘The conclusion is clear. CO2 cannot be the primary driver of temperatures.”

        1. You havent presented one single bit of data to show this.
        2 You havent done one single bit of math to show this.
        3. Your claim is absolute, worse than anything real scientists do.

      • Javier,

        You are wasting time with Jim D. You respond with science and he counters with examples such as David Archer, who wrote an alarmist book claiming 10 meters of SLR by end of century.

        It is CO2 all the way for Jim and anything to the contrary is automatically filtered out.

        And he says you have weird ideas.

      • Thank you Tim,
        I know Jim D has learned all the responses without understanding the science, and thinks this is a college debate that can be won by persistence.

        Dr. Judith Curry has dedicated a lot of effort explaining the uncertainty problem that we face in our current climate situation. It is important to know that regarding paleoclimate the CO2 hypothesis is even more uncertain and a lot of paleoclimatologists are showing evidence that we are not accounting correctly the effect of solar variability and greenhouse gases.

        If alarmists have trouble explaining current temperatures, they have even more trouble explaining past climate changes.

      • Peter Lang

        Javier,

        It; strange you’ll spend hours arguing with deniers like Jim D and Willard, but wont answer straight forward questions I ask you. The links to our previous discussion you posted instead of answering questions were to long exchanges where you repeatedly could not or refused to answer the question I asked. And, yes, after a while, I got frustrated and recognised you could not or would not provide a straight, clear concise answer.

    • You Cannot (with a capital C) meaningfully compare datasets that have two different integration times. To put them on the same plot is nonsense.

  6. All I see is an unaccountable,dramatic uptick. Contrivance comes to mind.

  7. Javier,you mention the need to increase others knowledge . I realize the subject at hand is post the last maximum ice age, however the time during the building of the continental ice sheet was another period of an extremely warm Arctic, about one hundred thousand years ago. The origin of man kind to NA fits into the end of this period also. What might have been the forcing at that time and is there any common factors to today’s warming trend? Atmospheric or ocean currents?

    • the time during the building of the continental ice sheet was another period of an extremely warm Arctic, about one hundred thousand years ago.

      What is the evidence for this?

      • Ice Core Data provides the evidence for this. The ice accumulates in the warmest time when polar oceans are high and warm. The accumulated ice then advances, spreads and causes the cooling for the ice age. As it cools, it continues to snow decreaingly as it cools. The really deep ice keeps flowing and ice extent increases cooling for many years after the ice volume maxes and starts decreasing. Ewing and Donn, 1950’s

  8. Pingback: Bits and Pieces – 20170528, Sunday | thePOOG

  9. “The complex planetary synchronization structure of the solar system, which since Pythagoras of Samos (ca. 570–495 BC) is known as the music of the spheres, is briefly reviewed from the Renaissance up to contemporary research. Copernicus’ heliocentric model from 1543 suggested that the Planets of our solar system form a kind of mutually ordered and quasi-synchronized system. From 1596 to 1619 Kepler formulated preliminary mathematical relations of approximate commensurabilities among the planets, which were later reformulated in the Titius-Bode rule (1766-1772) that successfully predicted the orbital position of Ceres and Uranus. Following the discovery of the ∼11 yr sunspot cycle, in 1859 Wolf suggested That the observed solar variability could be approximately synchronized with the orbital movements of Venus, Earth, Jupiter and Saturn. Modern research have further confirmed that: (1) the planetary orbital periods can be approximately deduced from a simple system of resonant frequencies; (2) the solar system oscillates with a specific set of gravitational frequencies, and many of them (e.g. within the range between 3 yr and 100 yr) can be approximately constructed as harmonics of a base period of ∼178.38 yr; (3) solar and climate records are also characterized by planetary harmonics from the monthly to the millennia time scales. This short review concludes with an emphasis on the contribution of the author’s research on the empirical evidences and physical modeling of both solar and climate variability based on astronomical harmonics. The general conclusion is that the solar system works as a resonator characterized by a specific harmonic planetary structure that synchronizes also the Sun’s activity and the Earth’s climate. The special issue “Pattern in solar variability, their planetary origin and terrestrial impacts” (Mörner et al., 2013) further develops the ideas about the planetary-solar-terrestrial interaction with the personal contribution of 10 authors.” https://arxiv.org/pdf/1405.0193.pdf

    The solar system is an n-body problem and in the strictest physics sense chaotic. We find small changes in insolation – including UV – producing large shifts in climate. It is the definition of abrupt change.

    “What defines a climate change as abrupt? Technically, an abrupt climate change occurs when the climate system is forced to cross some threshold, triggering a transition to a new state at a rate determined by the climate system itself and faster than the cause. Chaotic processes in the climate system may allow the cause of such an abrupt climate change to be undetectably small.” https://www.nap.edu/read/10136/chapter/3#14

    The theory suggests that the climate system is pushed by greenhouse gas changes and warming – as well as solar intensity and Earth orbital eccentricities – past a threshold at which stage the components start to interact chaotically in multiple and changing negative and positive feedbacks – as tremendous energies cascade through powerful subsystems. Some of these changes have a regularity within broad limits and the planet responds with a broad regularity in changes of ice, cloud, Atlantic thermohaline circulation and ocean and atmospheric circulation.

    It is all technically chaotic – not periodic at all in any strict sense. Just shifts in a multi-dimensional state space. Rejecting chaos gives some comfort that we can predict the evolution of climate (to cooling) I suppose – but I doubt if that’s the case.

  10. 8.2 kyr ago is cold on the Greenland GISP2 proxy, but 5.2 kyr ago is warm on GISP2. Though you have various alternative regional proxies to show that 5.2 kyr ago was otherwise a cold-dry period. The 8.2 kyr event is very warm on the Antarctic Vostok proxy, but very cold on GISP2. So which pole gets warmer during a cold event, and which pole gets colder?

    • which pole gets warmer during a cold event, and which pole gets colder?

      I suppose it depends on the nature of the cold event, which is not the same for the 8.2 kyr event and the 5.2 kyr event. The 8.2 kyr event had the contribution of the proglacial Lake Agassiz outbreak. And Antarctica is essentially responding through teleconnections, as it has pretty much its own climate, different from the rest of the world, as it does now.

      • The Arctic responds strongly through teleconnections controlling the rates of poleward oceanic and atmospheric heat transport. The Antarctic has comparatively very little, the unusual warmth of the 8.2 kyr event there requires an alternate explanation. There is no clear evidence that 8.2 kyr was a cold event other than in Greenland. It was though contemporary with the establishment of village settlements off the current coast of the Isle of Wight England growing wheat, village settlements in Sophia Bulgaria, and an early Harrapan expansion.

      • I recommend:
        Rohling, E. J., & Pälike, H. (2005). Centennial-scale climate cooling with a sudden cold event around 8,200 years ago. Nature, 434(7036), 975-979.
        http://www.academia.edu/download/46240278/nature0342120160604-24868-1ho1vi1.pdf
        They analyze 19 different proxies and they do definitely see cooling at 8.2 Kyr event.

      • Re. Rohling, E. J., & Pälike, H. (2005).
        Yes you have posted that before, and the comment I made was the Aegean sea and Craig cave show warm spikes centered at 8.2 kyr BP, and more importantly, intensified trade winds, which is the wrong sign to associate with a cold period.

      • Well, that’s the problem when not all the proxies agree. But as I said, there are plenty of proxies that indicate cold during the 8.2 kyr event.

      • At 5.2 kyr BP is a warm spike in GISP2, what do you have to say about that?

      • I seem to remember I already answered this one to you. Kobashi has demonstrated quite convincingly in my opinion that Greenland presents an opposite response to Northern Europe to low solar activity conditions.
        Kobashi, T., et al. “Causes of Greenland temperature variability over the past 4000 yr: implications for northern hemispheric temperature changes.” Climate of the Past 9.5 (2013): 2299.
        http://www.clim-past.net/9/2299/2013/cp-9-2299-2013.pdf

        So low solar activity -> colder North Atlantic -> warmer Greenland.

      • “So low solar activity -> colder North Atlantic -> warmer Greenland.”

        No way, low solar drives a warm AMO because it increases negative North Atlantic Oscillation conditions, and a warm AMO means a warm Greenland too. As we have seen since the mid 1990’s.

      • Kobashi is the foremost expert in Greenland paleoclimate and he bases his conclusions on multiple proxies. I don’t think you can dismiss all that only with your understanding and what has been taking place since the mid 1990’s.

      • Kobashi, T., et al:
        “We found that greenhouse gases played two important roles over the past 4000 yr for the rapid warming during the 20th century and slightly cooler temperature during the early period of the past 4000 yr”

        With rising greenhouse gas forcing modeled to increase positive North Atlantic Oscillation conditions, rising CO2 should then in theory inhibit warming phases of Greenland and the Arctic (and AMO).
        http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-3-5-6.html

      • “I don’t think you can dismiss all that only with your understanding and what has been taking place since the mid 1990’s.”

        It actually agrees with this :
        “Therefore, it can be expected that stronger (weaker) solar activity induces warming (cooling) in NH temperature, and relative cooling (warming) in Greenland through positive (negative) NAO. Consistent with this theory, Greenland temperatures have deviated negatively (positively) from the NH temperature trend when solar activity was stronger (weaker) over the past 800 yr (Kobashi et al., 2013). Climate modelling also indicates that the Atlantic meridional overturning circulation (AMOC) reduces (increases) during weaker (stronger)
        solar activity”

      • Ok, then we agree that the evidence supports that weaker solar activity induces cooling in NH temperatures and relative warming in Greenland through negative AMO.

        Then apply that to the 5.2 kyr event and you can see why GISP2 should not display much cooling when the rest of NH did.

      • If you had said ‘So low solar activity -> colder NW Europe -> warmer Greenland’, rather than ‘colder North Atlantic’, I could begin to agree with you. Take the colder run of years in for England during the 1880’s solar minimum, the AMO was warm then.
        https://climexp.knmi.nl/data/tcet.dat

      • North Atlantic proxies like the Bond series correlate quite well with NW Europe proxies and very poorly with Greenland ice cores. I fail to see the distinction. It seems to me that you are giving too much importance to the AMO. Most authors highlight the role of AO/NAO in determining climatic conditions in the North Atlantic realm, that includes NW and SW Europe.

      • “Ok, then we agree that the evidence supports that weaker solar activity induces cooling in NH temperatures and relative warming in Greenland through negative AMO.”

        No the AMO is warm when Greenland is relatively warmer, because both are driven by increased negative North Atlantic Oscillation.

      • Sorry, I should have said negative NAO. This letter soup sometimes gets me.

      • “It seems to me that you are giving too much importance to the AMO.”

        Actually I considered it important to address your claim that:
        ‘colder North Atlantic -> warmer Greenland’.

      • “I suppose it depends on the nature of the cold event, which is not the same for the 8.2 kyr event and the 5.2 kyr event. The 8.2 kyr event had the contribution of the proglacial Lake Agassiz outbreak.”

        And what if the final drainage event of Lake Agassiz was actually at 8.4 kyr BP (or 8.475 kyr from some sources), where GISP2 has a warm spike?
        And why should a global cooling event cause a sharp ~3°C rise in the Vostok ice core proxy at 8.2 kyr BP?

        http://tsunamisociety.org/233murty.pdf
        http://www.enn.com/top_stories/article/43359

      • The exact date and effect of the Lake Agassiz outbreak are still open to debate. I would think that the best proxy to identify it would be North Atlantic salinity. Thornalley et al., 2009 show a very clear freshening spike at the right time.

        why should a global cooling event cause a sharp ~3°C rise in the Vostok ice core proxy at 8.2 kyr BP?

        Perhaps it didn’t. These are the dangers of relying on a single proxy. There are numerous East Antarctic ice cores and the only one that displays warming is Vostok. In fact Masson et al., 2000 reconstruction of East Antarctica temperatures from numerous cores shows one of the three coldest periods of the Holocene at 8 kyr BP.

        In my opinion the unique methane downward spike at 8.2 kyr BP in Antarctic records is likely to be tied to the other unique event that we know at the time, the outbreak of Lake Agassiz. Although the effect could have some delay, it allows to date it within a few decades.

      • “In fact Masson et al., 2000 reconstruction of East Antarctica temperatures from numerous cores shows one of the three coldest periods of the Holocene at 8 kyr BP.”

        And GISP2 shows one of the three warmest periods at ~7950 yr BP.

        “In my opinion the unique methane downward spike at 8.2 kyr BP in Antarctic records is likely to be tied to the other unique event that we know at the time, the outbreak of Lake Agassiz. Although the effect could have some delay, it allows to date it within a few decades.”

        The final lake drainage event could easily have been 200-275 years before 8.2 kyr BP. I don’t any rational reason to not include the 8.2 kyr event as a regular polar see-saw event of the Holocene. The issue is the sign of climate forcing. And as the two next coldest periods in GISP at ~3740 years later around 4800-4450 BP, and another 3740 years later in the 8th century AD were very warm for the mid latitudes, I expect to see more archeological evidence for human settlement and trade expansion close to 8.2 kyr BP, to add to the three examples I gave above.
        Through the glacial period there were huge D-O events up and down that didn’t seem to perturb the Antarctic much and must have involved considerable melt events. And I don’t believe that there is any such strong negative feedback to the Antarctic to account for the 8.2 kyr warm spike.

      • to account for the 8.2 kyr warm spike.

        What 8.2 kyr warm spike?
        Dome C doesn’t show it
        Taylor Dome doesn’t show it
        Law Dome doesn’t show it
        Komsomolskaia doesn’t show it
        Byrd doesn’t show it
        Dominion Range doesn’t show it

        There wasn’t a warm spike in Antarctica at 8.2 kyr BP.

      • “There wasn’t a warm spike in Antarctica at 8.2 kyr BP.”

        There is in the Vostok core. I’ll study the others. Byrd for starters seems to have resolution problems in that period.
        http://lgge.osug.fr/personnels/CHAPPELLAZ_Jerome/publications/a20.pdf

        And typo in my previous comment, 3470 yrs not 3740 yrs. This also fits warm spike intervals in GISP particularly well.

      • Padre Cave in Brazil shows it wetter through 8.2 kyr BP, that should be less El Nino for that region of Brazil to be wetter. The same for a drier southern China for the Dongge Cave, and the Qunf Cave in Oman.
        https://www.geo.umass.edu/climate/papers2/Cheng_Geology2009.pdf

      • Dongge cave stalagmite D shows at 8.2 kyr the usual Asian monsoon weakening that takes place during periods of low solar activity.

      • From an ENSO perspective low solar would increase El Nino, and drive a drier northern China and a wetter south.
        This ENSO proxy (fig 5) shows El Nino intensity increasing a couple of hundred years after 8.2 kyr where GISP is naturally warm again, as El Nino episodes are a driver of Arctic warming.
        With Rohling, E. J., & Pälike, H. (2005) showing a well timed increase in trade wind speed at 8.2 kyr, the event obviously involves global teleconnections, and of the wrong sign to be a global cold event.

        http://www.clim-past.net/6/525/2010/cp-6-525-2010.pdf

      • “From an ENSO perspective low solar would increase El Nino

        That’s not what the evidence supports. You can compare that ENSO proxy with a proxy for solar activity and see for yourself.

      • Low solar increases negative North Atlantic Oscillation states, and negative NAO is directly associated with slower trade winds. El Nino episodes increase in frequency through the weaker phases of solar minima.

      • El Nino episodes increase in frequency through the weaker phases of solar minima.

        If this was true, you should be able to show it by comparing the Moy et al., 2002 Laguna Pallcacocha ENSO proxy and a solar activity reconstruction, like the one from Steinhilber et al., 2012. Have you tried or is it just a theoretical conjecture?

      • Fig 5 in my last link is from Moy et al, and shows much weaker El Nino around 8.2 kyr BP.
        I would first argue that slower solar wind periods drive negative NAO and slower trade winds and hence El Nino episodes, at an event level. And that specific phases of solar minima have greatly increased frequency and intensity of negative NAO periods. For the Dalton Minimum it was roughly between the sunspot maxima of solar cycles and 5 and 6, from 1807 to 1817. Which was the coldest part of Dalton for England. https://climexp.knmi.nl/data/tcet.dat
        SM Silverman – ‎1992 shows a dearth of aurora sightings for most of the years 1807-1817, and the mean El Nino frequency roughly doubled through the period.
        https://sites.google.com/site/medievalwarmperiod/Home/historic-el-nino-events

      • We have about 11,000 years of data. Why are you talking vaguely about “around 8.2 kyr BP.” and about “from 1807 to 1817.”? Is the rest of the data not good or not supportive of your conjecture that low solar activity is linked to enhanced ENSO activity?

      • “Why are you talking vaguely about “around 8.2 kyr BP.””

        Why do you say vaguely? El Nino intensity was reduced around 8.2 kyr BP.

      • El Nino intensity was reduced around 8.2 kyr BP.

        El Niño intensity was reduced during the entire Holocene climatic optimum, including the 9th millenium BP.

      • “Is the rest of the data not good or not supportive of your conjecture that low solar activity is linked to enhanced ENSO activity?”

        Well look at Moy et al, the early LIA has the most intense events of the series. I used the Dalton Minimum case as there is good information on El Nino episodes as well as the aurora observations, to correlate to the specific part of the solar minimum when the bulk of negative NAO and cold for NW Europe occurred.

      • “From an ENSO perspective low solar would increase El Nino”

        “El Nino episodes increase in frequency through the weaker phases of solar minima.”

        I just don’t understand why you talk and talk and won’t even check the data to see if it is supportive of what you say or not.
        I’ll show you how this is done. You take Moy et al., 2002 ENSO proxy, of which you have talked so much. And you take a solar activity reconstruction, for example Solanki et al., 2004 sunspot reconstruction.
        https://www1.ncdc.noaa.gov/pub/data/paleo/paleolimnology/ecuador/pallcacocha_red_intensity.txt
        https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/solar_variability/solanki2004-ssn.txt
        And then you plot them to see if your conjecture is supported by the evidence or not.

        I have marked with an asterisk periods of very low solar activity (grand solar minima) that do not coincide with periods of high ENSO activity. With hollow circles periods of very low solar activity (GSM) that coincide with periods of reducing ENSO activity (higher ENSO activity at the beginning of the GSM that at the end). And with black triangles peaks of ENSO activity not associated to low solar activity. All that is left is a couple of spots with question marks.

        The conclusion is clear. Periods of very low solar activity that define grand solar minima not only do not increase ENSO activity. They appear to inhibit ENSO activity when it was high at the time the GSM started. So you have it backwards. Low solar activity decreases El Niño episodes frequency.

        Now you can do two things. You can reject your conjecture or you can reject the evidence. What will it be?

      • “I have marked with an asterisk periods of very low solar activity (grand solar minima) that do not coincide with periods of high ENSO activity. With hollow circles periods of very low solar activity (GSM) that coincide with periods of reducing ENSO activity (higher ENSO activity at the beginning of the GSM that at the end). And with black triangles peaks of ENSO activity not associated to low solar activity. All that is left is a couple of spots with question marks.”

        I see some hollow circles where ENSO is high. With grand solar minima each not being more than 50 years in duration, a chart with 100 yr averaging doesn’t suit the purpose. I would compare ENSO against a geomagnetic proxy over a shorter period.

        “The conclusion is clear. Periods of very low solar activity that define grand solar minima not only do not increase ENSO activity. They appear to inhibit ENSO activity when it was high at the time the GSM started. So you have it backwards. Low solar activity decreases El Niño episodes frequency.”

        Your conclusion is far from clear. El Nino activity did increase in the coldest part of the Dalton Minimum, and you can see that El Nino activity increased earlier in the LIA and the Antique LIA in you own chart. So you have it backwards. Earlier in the Holocene stronger solar due to orbital factors would have raised the threshold for solar variability to initiate El Nino episodes. I don’t see how you can argue against the logic that weaker solar increases negative North Atlantic Oscillation states, and that negative NAO is directly associated with slower trade winds and hence increased El Nino.

        “Now you can do two things. You can reject your conjecture or you can reject the evidence. What will it be?”

        Your evidence is specious, and you have rejected mine.

      • Your evidence is specious

        That is a most common attitude these days. I don’t know if the scientific method has stopped being taught or what but lot of people, including scientists, are so in love with their conjectures and hypotheses, that when contradicted by empiric evidence they question the evidence. Same with CO2 hypothesis that temperature data must be wrong or in need of adjusting if not showing warming.

        I have used the same evidence you talk about so much, Moy et al., 2002, and it does not support your conjecture. You should have been the one doing the checking before spreading your conjecture around, and I invited you to do it. Your answer when presented the evidence is not the right one. I have little time for people that promote conjectures and reject the evidence that contradicts them. Do all the checking you need to do or not. That’s your problem.

      • You have not contradicted anything as your hollow circles by periods of low solar are mostly coincident with higher El Nino. You should have been the one doing the checking before spreading your conjecture around. I have supplied a few lines of empiric evidence of increased El Nino frequency through the Dalton Minimum, and Moy et al shows increased El Nino through the LIA. Who is to say that the Solanki solar proxy maps all GSM’s well anyway, it shows no GSM for the early Antique LIA. or the GSM at around 3200 and 4200 BP. One could do far better with an empirical model of past grand solar minima.
        And why are El Nino weaker between 2750-3250 BP in this chart compared to the original?

      • why are El Nino weaker between 2750-3250 BP in this chart compared to the original?

        Have you actually read Moy et al., 2002? This is the graph they present in their figure 1a. Number of ENSO events per 100 years.

      • OK so the other one is intensity and this one is frequency.
        https://sci-hub.cc/10.1038/nature01194
        The bottom line is that negative NAO increases through solar minima, and negative NAO is directly associated with slower trade winds and hence increased El Nino. I rest my case.

      • Moys and colleagues measured red sediment intensity – low red intensity is La Nina and high El Nino. It is base on the hydrological impacts of ENSO. More (less) rain in the lake catchment is El Nino (La Nina). More rain washes more red sediment into the lake. Thus there was a shift from La Nina dominance prior to 5000 years BCE – to El Nino dominance – higher frequency and intensity – since. It’s a terrific proxy but the interpretation here is a bit haphazard.

        Over the past 1000 years we have seen a El Nino peak followed by centuries of high La Nina frequency and intensity – and higher rainfall in Australia – until the 20th century. More salt in the Law Dome ice core is La Nina.

        Eyeballing it in and the patterns of solar and ENSO variability seem obvious – but one to one correlation does not work at all. Low solar activity favours La Nina and vice versa.

        The mechanism is UV/ozone chemistry modulating both the northern and southern annular modes – spinning up winds and currents at lower latitudes and biasing the system to more or less upwelling in the eastern Pacific.

      • Robert I. Ellison writes:
        “Low solar activity favours La Nina and vice versa.”

        Increased negative NAO is observed through solar minima, and negative NAO is directly associated with slower trade winds and hence increased El Nino.

        “More salt in the Law Dome ice core is La Nina.

        I’m not buying that, there was not increased La Nina through the Dalton Minimum. Look at the 1970’s:
        https://www.researchgate.net/publication/248801967_A_700-Year_Record_of_Atmospheric_Circulation_Developed_from_the_Law_Dome_Ice_Core_East_Antarctica

  11. Javier, where is the evidence of a warm Arctic entering the last major ice age?

    Looking for information, I am not aware of any papers addressing this , do you? What was the source of water vapor large enough to build such ice sheets? The Rockies shut out Pacific Ocean moisture from the west, central Canada normally does not receive Atlantic weather, unless systems moved north from the Gulf of Mexico the Arctic would need to be somewhat ice free. Presently it is June before significant water vapor arrives on the prairies from the north, after the Precambrian Lakes become ice free. Typical air is warm dry from the Pacific and cold dry from the Arctic. I do recall a paper last winter on Climate Etc. That suggested an area north of the Berring Strait, called Berinia existed as a temperate grassland during the LGM. I assume that needed to be well into the last ice age after ocean draw down. Any source of information would help. Thanks.

    • carlfrohaug,

      That your model requires an Arctic free of ice during the build up of the continental ice-sheets ~ 100 kyr ago, doesn’t mean that the Arctic was free of ice at that time. The climate during glacial periods is quite different and the moisture could be brought from lower latitudes by the atmosphere. It is an awfully long process that could take place even under much lower snow precipitation rates as now, as long as the balance is heavily tilted towards ice build up, with very little melting.

      I am not aware of any sea-ice proxy that extends so far back. We know that during the LIA sea-ice reached Scotland in the winter, so it is very counter-intuitive that under much colder glacial conditions sea ice would actually be reduced.

      • There is ice core data for Antarctica that goes back 800 thousand years.
        There is NEEM data for Greenland that goes back 150 thousand years.

        This is well known documented data. I don’t know why you are not aware.

        O

      • You seem to ignore that ice sheets and ice caps accumulate over land, where ice-cores can be taken, while sea ice accumulates … well over sea. Ice cores provide no evidence about sea ice.

  12. Note co2 concentrations were lower during the Minoan, Roman , and Medieval Warm periods which were as warm or warmer then today.

  13. The good news is that the so called modern warming period is now in the process of ending(now – through coming years) as solar activity is becoming very weak and will become weaker as we move forward.

    I expect global mean temperatures to be at or below 30 year average means within the next 12 months.

    I think it is a very low solar/increase albedo /lower overall sea surface temperature play that will result in lower global temperatures as we move forward from here.

    Low solar – If solar irradiance deceases say by .15% that is a .2c reduction in global temperatures just do to that factor alone.

    Increase albedo – even a 1/2 of 1% increase will result in a significant global temperature drop. Albedo should increase in response to very low solar conditions which should result in an increase in major volcanic activity , increase in global cloud coverage and sea ice/snow coverage.

    Increasing galactic cosmic rays being a main factor for major volcanic activity to increase and global cloud coverage to increase while less EUV light should result in a more meridional atmospheric circulation which would also result in more clouds and also greater snow coverage.

    I think at the start of global cooling the atmospheric circulation becomes more meridional only later to transition to a more zonal circulation.

    Overall lower sea surface temperatures – this should happen as a result of weakening UV light which penetrates the ocean surface to significant depths which should impact the surface ocean temperatures.

    My solar criteria which is now coming into play are

    solar flux 90 or less

    solar wind 350 km/sec or less

    cosmic ray counts 6500 units or greater

    euv light less then 100 units and uv light lessening just below visible light wavelengths

    solar irradiance off by .15%

    imf – 4.2 nt or lower

    ap index – 5 or lower but isolated spikes which could contribute to an increaae in geological activity

    All of this in combination with a weakening geo magnetic field which should compound given solar effects.

    The test is on now that solar is finally reaching my cooling criteria and if global temperatures do not drop despite these low solar conditions I will be wrong, on the other hand if they do I think we will have to conclude that AGW theory is dead.

    In the big picture Milankovitch cycles are favorable on balance and the land /ocean arrangements are very favorable for global cooling.

    Precession /obliquity — Precession very favorable while obliquity is lessening and becoming more favorable as compared to the Holocene Optimum period of time and this is why I think the global temperatures in general have been on a decline overall since the Holocene optimum however with fits and starts due to solar activity changes /volcanic activity and enso superimposed upon this general trend.

    Note Javier does not accept the major volcanic /low solar correlation and is convinced with out any real evidence that this low solar period will not be that severe. We shall see.

    • Javier does not accept the major volcanic /low solar correlation

      While I can believe in six impossible things before breakfast, after breakfast I restrain myself to believe only in things supported by evidence. Spurious correlations are the bane of scientists with little rigor. Find the unambiguous evidence and I will believe that the sun controls volcanoes.

      • AbstractSolar activities eject high energetic particles, instead of electromagnetic radiation. The well-know solar activity main indicator is the existence of sunspot which has mean variation in 11 years, named by solar cycle. Solar activities are related to the space weather affecting all planets atmospheric variability, moreover to the Earth’s climate variability. The big question arises to the relation between solar forcing energy to the Earth’s global volcanic activities. We search its connectivity from yearly volcanic activities refer to Volcano Explosive Index (VEI) and sunspot number within year of 1900 to 2013 (113 years) which represent the global warming period and the range of Maunder minimum within year of 1615 to 1751 (136 years) which known as the global cooling period. We found that the declining solar cycle significantly show more volcanic activities (VEI=1 to 5) with more than 40% occurrences for both warming and cooling periods. They have mean occurrences of (50.1±4.5) % and (42.0±10.4) %, respectively. In the rising phase of solar cycle, the average occurrences are (27.1±3.3) % and (28.8±5.3) %, respectively. When we selected the interval time in 3 years around the peak of maximum and minimum of the solar cycle, the global warming period had average of (27.1±5.5) % and (32.1±4.4) %, respectively and the global cooling period showed an average of (32.7±11.1) % and (21.3±5.0) %, respectively. The minimum phase showed higher frequency events of volcanic activity than the maximum phase during the warming period, opposite to the cooling period. Although the physical reason is far for explanation, we argue that solar activities have a clear relation with global volcanic activities.

        On the Relation between Solar and Global Volcanic Activities (PDF Download Available). Available from: https://www.researchgate.net/publication/268513239_On_the_Relation_between_Solar_and_Global_Volcanic_Activities [accessed May 29, 2017].

        One of many studies Javier.

      • Sorry Salvatore, you and I don’t have the same standard for what constitutes evidence.
        Your link is a conference presentation where since it is not peer-reviewed, you can pretty much defend that the earth is flat. The conference took place in 2014. We are now in 2017, three years later, and the work has not been published. I bet you they won’t publish it.

        You have such low standards because you are a believer. You believe in things and require very little evidence as you are pre-convinced. On the other hand I am a skeptic by personal conviction and training. You won’t convince me with a conference presentation in a million years. Not even with a published peer-reviewed article. I’ve been in this business long enough to know that most published things in scientific journals are actually not correct, so imagine the situation outside science.

        So color me unimpressed by your evidence.

      • http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?2003ESASP.535..393S&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.
        2003ESASP.535..393S

        Jaroslav StreStlk
        Geophysical Institute AS CR, Bocni 11 1401, 141 31 Prague, Czech Republic, Email: xxx@XXX.xxx

        Abstract:

        Volcanic activity on the Earth is described by special
        annual indices available since 1500. These indices have
        been compared with annual sunspot numbers. Volcanic
        activity displays no ll-yr periodicity. Using 2l-yr
        running averages a striking similarity between these
        two time series is clearly seen. Volcanic activity is
        generally lower in periods of prolonged maxima of
        solar activity and higher in periods of prolonged solar
        minima. There is also a similarity between the spectra
        of these two series in the long-period range. Main
        peaks are located in the same periods in both series
        (200-215 yr, 100-105 yr, 80-90 yr). The influence of
        volcanic activity on the climate is indubitable. Annual
        means of surface air temperature display similar longterm
        periodicity as the volcanic activity.

        Conclusions:

        The narrow similarity between solar and volcanic
        activity in the long-term scale suggests two quite
        different possible consequences:
        a. Solar activity governs the volcanic activity on the
        Earth in long-term scale. Volcanic activity is
        usually higher in periods of prolonged minima of
        solar activity and vice versa. However, the
        mechanism of this forcing is not known. Perhaps
        geomagnetic activity mediates solar influences
        (unfortunately, series of these data are too short). If
        it will be confirnled in the future, then solar
        influences on the climate could be considered as
        being mediated by the volcanic activity, creating
        a chain: solar activity – (geomagnetic activity) –
        volcanic activity – climate changes. Direct solar
        influence on climatic changes is, of course, not
        excluded. But it is difficult to distinguish what part
        of these changes is mediated by volcanic activity
        and what part is direct solar influence. It would be
        also necessary to explain why this chain does not
        work in short-term scale.
        b. The similarity of the long-term course of solar and
        volcanic activity is accidental and is pronounced
        only in the last few centuries. Then long-term
        natural climatic changes would be caused only by
        long-term changes of volcanic activity. The role of
        solar activity would be in this case only apparent
        due to the accidentally sin1ilar course of both
        activities during the last five centuries.
        Nevertheless, some small direct solar influence is
        not excluded. In this case no similarity in shortterm
        scale can be expected and it is not necessary to
        look for an explanation why it is not observed. These two different conclusions mean that the
        investigation of solar, volcanic and climatic changes
        together in a considerably longer period (at least one
        millenium) is very desirable.

        aaron

      • Yes Aaron,
        I am aware, in fact have a copy, of Strestik 2003. The analysis is only from 1500. I subscribe to the b) explanation. The association is only apparent.

        Correlation is not causation, and in this case the correlation is for only 500 years when we have data for at least 12000 years. Alternative explanations are available, for example that climatic changes are responsible for changes in continental ice mass that affect volcanic activity.

        So this is a case where the evidence is inconclusive, and a mechanism completely unknown. No wonder that almost nobody considers it.

      • When I did my own ad hoc look at VEI, the only thing that didn’t look “random”/like white noise was the maunder minimum. iirc, it was more low VEI activity and less high VEI events.

      • I agree. I think there is a lot to explore here.

        Some possibilities are CRF affects the chemistry and circulation of volcanoes similar to how CCN are ionized in the atmosphere. Ionized molecules could be affected by magnetic field affecting circulation subtly. They could also affect the chemistry of the emissions and how they behave in the atmosphere. (could this also similarly affect ocean circulation?)

        Could be that the changes in volcanic activity are the reason we didn’t see much solar activity.

        I’m not sure how to go about exploring this, Lubos Motl had suggest a way to look at possible magma pressure/circulation changes when I floated the idea 10 or so years ago.

      • Well, one possibility would be to analyze volcanic activity and 14C production data for the past 11700 years. If we cannot find a correlation there, then it is likely that there is nothing.

    • Salvatore del Prete: I expect global mean temperatures to be at or below 30 year average means within the next 12 months.

      Want to elaborate? Say, at least for 7 months beginning no later than 11 months from now?

    • The good news is that the so called modern warming period is now in the process of ending(now – through coming years) as solar activity is becoming very weak and will become weaker as we move forward.

      Why is it good news if the modern warming period is ending? I would consider this very bad news, not good news.

  14. https://www.bing.com/videos/search?q=the+coming+ice+age+video+john+casy&view=detail&mid=92902CA8302204515EFB92902CA8302204515EFB&FORM=VIRE

    Finally a video which I am on board with.

    What is most important is where does the climate go from here , and I have said this is the end of the warm period . I am calling for a turn in the climate as opposed to being safe and going with the status quo which 98% or so of climate scientist do.

    • NOTE JAVIER AND OTHERS MY SOLAR PARAMETERS ARE JUST NOW STARTING TO BE MET , PRIOR TO THIS TIME 2010-2016 THE SOLAR PARAMETERS WERE WELL ABOVE THE VALUES I SAID WOULD BE NEEDED TO CAUSE A GLOBAL COOL DOWN, NOW FINALLY THIS IS CHANGING.

      I EXPECT A DEFINITIVE COOLING TREND WITHN A YEAR OR SO.y

  15. Bray cycle (it’s the stun)–

    “…the occurrence of grand minima depicts a weak (marginally significant) quasi-periodicity of 2000–2400 years, which is a well-known period in 14C data… no clear periodicities are observed in the occurrence of grand maxima.” ~Usorkin

    • Ah yes. The climatic effect of the solar cycle is mainly due to long periods of sustained below average solar activity. That’s why a modern grand solar maximum is not required to explain a great deal of post-LIA warming.

      I will be dedicating the next article/s to the Bray cycle. A lot of people might be surprised how strong is the evidence, and how important it has been for Holocene climate so far.

      • Wow! Ice Extent is more in cold times and less in warm times, ALLWAYS!

        All these other correlations that are supposed to cause changes in temperature that results in changes to ice extent. That is just totally backwards.
        I don’t know what a Bray cycle is, but if it is not warm ocean causing snowfall that causes cooling or cold frozen ocean that causes less snowfall allowing warming, you clearly do not have a clue to what really regulates climate.

  16. where does the climate go from here

    It proceeds similar to the Minoan, Roman , and Medieval Warm periods.
    It is snowing more now due to warm open oceans and the snow will persist until ice volume is sufficient to cause cooling. Ice core data shows that this is what happens. Ice volume is a result of snowfall rates. Ice extent is a result of Ice volume. Temperature is a result of ice extent.

    The NH and SH temperature regulation works the same and they do not need to be in phase, except for major cycles. Major cycles are colder at about the same time and warm at about the same time because ocean levels, availability of warm thawed ocean water does play a part in this. Cycles of the most recent 20 thousand years have been in and out of phase, compare ice cores from NH and SH.

  17. The Last Glacial Maximum and the HCO constitute two extreme metastable states, separated by only 10,000 years, that correspond to essentially the same amount of incoming energy from the Sun. The main difference between both states is in the redistribution and minimal or maximal exploitation of that energy by the planet.

    Can we not also point out that these two states are attractors in a chaotic-nonlinear system? Local minima of improbability in the probabilistic landscape?

  18. Javier, again thanks for pulling this together. Bookmarked. My own paleoclimate research did not go much beyond debunking Shakun and Marcott (essays Cause and Effect and A High Stick Foul, respectively). This is another very helpful overview.

  19. We have just had a mini heatwave in the UK and I measured the maximum temperature at 26.2 degrees centigrade where I am in the UK. These are caused we are told by plumes of warm air coming off the continental European surface . If these plumes of warm air operated in the same way during the last glaciation as they do know then they would make short work of ice sheets that were hanging around because of the albedo effect, this is possible because not all the northern hemisphere mid latitude land surface was covered with ice throughout the period of glaciation and might explain why glaciations terminate quickly

    • If these plumes of warm air operated in the same way during the last glaciation as they do now…… In a glaciation the plumes of warm air might just be…not so warm?

  20. Javier, a great review paper. Thanks. You say: “A further complication arises because some climate periodicities do not show the behavior of proper cycles and present gaps when the signal cannot be detected in the data.” In my view these complications arise because no proper distinction is ever drawn between “proper” periodic cycles and random fluctuations. The term “non-periodic cycle” is an oxymoron. Spectral analysis of Holocene proxy temperature, e.g. GISP2 indicate that its apparent cycles are just red noise (Fig 4 of http://blackjay.net/wp-content/uploads/2016/08/0958305×16686447.pdf). Truly periodic behaviour is evidence of astronomical forcing, e.g. by insolation cycles. Likewise Dansgaard-Oeschger events are just that, events, not cycles. They appear to be the outcome of a Poisson process. The observation that, unlike terminations, they correlate well with the 10Be flux suggests an external origin (see: Beryllium and Climate, http://blackjay.net/?page_id=93).

    • Dansgaard-Oeschger events are the manifestation of an underlying regular cycle. Due to their nature D-O events require a set of circumstances that if not present they don’t manifest. The manifestation of the cycle is climatic, and thus subject to climatic factors.

      • I agree with your “set of circumstances” – they are not observed during interglacials. What is the period of the “regular cycle” and why are Dansgaard-Oeschger events alone associated with excursions in the 10Be flux?

      • Hi John,
        Although proposed at 1470 years based on a single ice-core, GISP2, more recent data suggests it is closer to 1500 than 1470 years.
        The D-O association with excursions in the 10Be flux can be explained because 10Be shows a strong climatic deposition-dependence. Essentially all the chemical species in Greenland ice cores show the same association with D-O events indicating that 10Be is behaving as an atmospheric chemical species during glacial periods.

  21. Javier, your essay is very interesting.

    I was recently reading about the effects of oxygen on the paleo climate and am curious if your research incorporates such proxy data? My interest was driven mostly by the basic comments and questions being asked by climate scientist Chris Poulsen only a couple years ago that served as a foundation for his research, it was his query relative to the role of O2 that intrigued me: “…most thought oxygen’s role has been negligible”. Thought? Assumption? “…whether oxygen levels might somehow have affected climate in the past”. Are these the types of questions one asks if the science is settled? Probably not today if they were asked and settled 30 or 40 years ago, but I presume they weren’t when considering data collection on O2 in combination with CO2 has only been collected a couple decades, and he’s asking the questions; his paper is only a couple years old. Dr. Poulsen’s questions in many ways are more interesting than any conclusions he arrives at when the science was already supposed to be settled, yet his questions are so basic. While O2 is not a GHG, its complex climate interactions are many, i.e., more atmospheric water vapor, but also clouds.

    University of Michigan climate scientist Chris Poulsen, lead author of the study “Long-term climate forcing by atmospheric oxygen concentrations” in Science. “…Poulsen and his colleagues were studying the climate and plants of the late Paleozoic, and during a meeting they started talking about whether oxygen levels might somehow have affected climate in the past. Studies have shown that atmospheric carbon dioxide has been the main climate driver through deep time, so most thought oxygen’s role has been negligible.”

    http://science.sciencemag.org/content/348/6240/1238

    Earth’s Oxygen Levels Can Affect Its Climate. Models of past eras show that oxygen can influence global temperature and humidity as its concentration changes http://www.smithsonianmag.com/science-nature/earths-oxygen-levels-can-affect-its-climate-180955572/#hoMrlHCMAG490qFd.99

    Global CO2 records go back more than 50 years [8], but O2 measurement in combination with CO2 goes back barely two decades [9].
    Measuring O2 and calculating land and ocean carbon sinks

    It is difficult to measure changes in O2 because there is so much of it in the atmosphere compared with CO2. So a proxy is used instead. Changes are measured as differences in O2/N2 ratios expressed in “per meg” units against the ratio in a standard mixture kept at the Scripps Institute of Oceanography which pioneered the measurement.
    http://www.i-sis.org.uk/O2DroppingFasterThanCO2Rising.ph

    • Mop-Up-Crew,

      I have no doubt that O2 levels must have affected climate as Dr. Poulsen defends. One can only wonder how huge forest fires must have been during the Carboniferous or Late Cretaceous under higher oxygen conditions. Also changes in levels of oxygen should affect levels of ozone that is the main greenhouse gas in the stratosphere and is thought to have a very important role in climate. I completely agree that we ignore a lot more about climate change than what we know. But I don’t do research on climate. My only role is to read the scientific literature and try to give a more coherent picture of what the evidence indicates. If we don’t know about past climate history, we might accept claims that are clearly outrageous about how exceptional is our climate.

      • Thank you for the response, Javier.

        I’ve contemplated that while so much data has been collected on CO2 it seems there’s little attention paid to O2’s effects on future climate. For example, while most of the emphasis is on modeling the CO2 curve, there’s little consideration I’ve seen towards an increased O2 curve; but we’ll get an increased O2 curve with substantial greening of the planet caused by higher CO2 levels. More moisture means more clouds, thus albedo, more snow, etc., although too, moisture is a GHG. Obviously very complex. Between 1982-2010 there was an 11 percent increase in foliage across much of the planet. This should have increased since then, and continue unabated until peak CO2. More alternatives will mean consuming less O2, so the the O2 curve should steepen as more alternatives are brought online.

        In findings based on satellite observations, CSIRO, in collaboration with the Australian National University (ANU), found that this CO2 fertilisation correlated with an 11 per cent increase in foliage cover from 1982-2010 across parts of the arid areas studied in Australia, North America, the Middle East and Africa, according to CSIRO research scientist, Dr Randall Donohue.

        https://wattsupwiththat.com/2013/07/08/deserts-greening-from-rising-co2/

      • My pleasure Mop-Up-Crew,

        Paleodata and recent measurements agree that CO2 and O2 are inversely correlated, as they are the same O atoms. So the increase in CO2 is accompanied by a decrease in Oxygen. Not to worry as there is plenty more. Plants are fighting this process taking CO2 and releasing O2 and greening the planet as a consequence.

        The latest article on greening I’ve seen is from a couple of months ago:
        “Human population growth offsets climate-driven increase in woody vegetation in sub-Saharan Africa”
        https://www.nature.com/articles/s41559-017-0081
        Thanks to climate change and CO2 increase the balance is positive towards greening over human deforestation.

      • “Paleodata and recent measurements agree that CO2 and O2 are inversely correlated” Much appreciated, thus why I’m an enthusiast about the science. Thanks again.

  22. Javier lets see what happens.

  23. Increases in volcanic activity with associated with solar activity and as I write this Iceland is experiencing increasing chances of volcanic activity which this video talks about as well as showing the association of past ajor volcanic activity with solar minimums.

    The data shows it .

    • What data?. You just moved from a conference presentation to a Youtube video. This cannot get any lower, can it? What’s next? A cartoon that demonstrates it?

  24. > Instrumental-era climatologists and astrophysicists are however very skeptical of such periodicities

    Evidence?

    ***

    > Similar objections were made to Alfred Wegener’s continental drift theory that despite solid evidence from geography, geology, paleontology, and biology, was shunned until the development of plate tectonics theory could explain how continents drifted.

    Continental drift is a really old idea, and it’s rather the centrifugal pseudoforce that hit a wall. That did not prevent Holmes to propose an alternative mechanism for it which got some traction after its empirical support increased:

    Not until the 1960’s did Holmes’ idea receive any attention. Greater understanding of the ocean floor and the discoveries of features like mid-oceanic ridges, geomagnetic anomalies parallel to the mid-oceanic ridges, and the association of island arcs and oceanic trenches occurring together and near the continental margins, suggested convection might indeed be at work. These discoveries and more led Harry Hess (1962) and R.Deitz (1961) to publish similar hypotheses based on mantle convection currents, now known as “sea floor spreading”. This idea was basically the same as that proposed by Holmes over 30 years earlier, but now there was much more evidence to further develop and support the idea.

    http://www.ucmp.berkeley.edu/geology/techist.html

    To paraphrase Kant, evidence without understanding is empty, and understanding without evidence is blind.

    • Immanuel Kant was not a scientist, and it shows. In science if you want to be correct more often than not you better stick to the evidence and go wherever it takes you.
      Darwin didn’t have an explanation for how variability was generated or how it could be transmitted through generations without dilution. All he had was the evidence that species were changing, and the idea from Malthus that differential reproduction had to be involved. He added sexual selection from his keen observation sense. As in the case of Weggener and despite some initial success, his theory fell into disregard by the late 19th century because it lacked a mechanism to explain the source of variability and its transmission. It wasn’t until the modern synthesis of the 1940’s when genetics was added to the theory, and later mutations, when his theory was finally accepted.
      The lesson with Darwin is the same as with Weggener. Stick to the evidence and the explanation will eventually come. Demand and explanation, when it is not possible due to the lack of knowledge, and delay scientific progress for decades.

      • Dear Javier,

        Your ad hominem is duly noted. Kant actually inspired Jean Piaget’s theories. According to the father of cognitive psychology, we’re all Immanuel’s grand-children.

        Please bear in mind that you’re just a pseudonym on a blog. While you did out yourself the other day, it hasn’t revealed any evidence of expertise in the history of science. Your misreading of Wegener’s story might express contrarians. Sidestepping my refutation of it with “but Darwin” does not impress me.

        “Sticking to evidence” is easier said than done, and leads nowhere without a theory, an explanation or at least a hypothesis. It is not by sticking to the evidence that tectonic plates came to be vindicated. It’s by getting more. And contrary to the Wegener myth contrarians peddle, the community went along as evidence came to be convincing.

        That you can’t derive theories from evidence alone is known since Hume at least. You know, the guy who inspired Kant to wake up from his dogmatism. I suggest you do the same.

        Meanwhile, you still haven’t provided the evidence I asked.

        So citations needed.

      • You seem to be very strong in Philosophy, an ancient discipline that is losing relevance and weight in the education with every passing generation. The likely reason is that Philosophy didn’t take us very far, because it was all theory and no evidence.

        You stick with the Philosophy, I will stick with the evidence.

      • > I will stick with the evidence.

        You can’t even do that with your Wegener story, Javier. Also note that equating science with “sticking to evidence” is far from being clear. Perhaps it’s a vocabulary thing:

        Both in and outside of philosophy, the concept of evidence has often been called upon to fill a number of distinct roles. Although some of these roles are complementary, others stand in at least some measure of tension with one another. Indeed, as we will see below, it is far from obvious that any one thing could play all of the diverse roles that evidence has at various times been expected to play. Different theories about the nature of evidence might thus naturally emerge from different emphases on the competing demands that have been placed on the concept. In what follows, I survey some of the theoretical roles that the concept of evidence has been asked to play and explore some of the relations among them.

        https://plato.stanford.edu/entries/evidence/

        “Sticking to evidence” is hard when storytelling. Some of your stories are more argumentative than evidentiary, e.g. the one about Bond events which we can read on thy Wiki. And as far as storytelling goes, you have yet to substantiate that “instrumental-era climatologists and astrophysicists are however very skeptical of such periodicities.”

        Citations still needed.

      • I didn’t get Wegener story wrong. He had geographical evidence, geological evidence, biological evidence and paleontological evidence. This was enough to convince some scientists at the time, but he was an outsider to the Geological field. If he had been a geologists of great reputation and power history might have been different. As it was he could have claimed as Galileo “E pur si muovono”, yet the continents move.

        Now let’s get a more recent example:
        Anthropologist Jacques Cinq-Mars in 1979 unearthed evidence at the Bluefish Caves that indicated that Asian hunters roamed northern Yukon at least 11,000 years before the arrival of the Clovis people. At the time North American Anthropology was dominated by consensus Clovis-first theory. Since Jacques Cinq-Mars evidence didn’t fit the theory it was ignored. Despite his ground-breaking discovery Cinq-Mars had a lowly career unearthing more and more evidence only to see it ignored. Other researchers came later with discoveries at Monte Verde in Chile in 1997 and finally the Clovis-first theory was put to rest. In 2012 Bluefish Caves evidence was re-examined and Cinq-Mars findings confirmed. By ignoring evidence and sticking to consensus career-building hypothesis the understanding of the peopling of the Americas was delayed two decades.
        http://www.smithsonianmag.com/science-nature/jacques-cinq-mars-bluefish-caves-scientific-progress-180962410/

        It is often the case that when science gets lost for decades is for ignoring evidence that contradicts dogma. Sticking to the evidence is the best advice for a scientist (unless he prefers a successful career to finding the truth).

        Citations still needed.

        Leif Svalgaard, personal communication.

      • > If he had been a geologists of great reputation and power history might have been different.

        Counterfactual thinking isn’t really evidence-based, Javier.

        Here’s some evidence both about your the story you could have told and the myth you’re entertaining:

        The paradigm shift in the Earth Sciences in the 1960s is often used as an example by climate change contrarians to argue that the science is never settled. Certainly, American geologists had formed a strong consensus against drift, but for the Europeans no such consensus existed: a real and unresolved debate about continental drift had been going on there for decades. In contrast, one of the features of the modern consensus on anthropogenic climate change is that it is nearly universal across international borders.

        What is astonishing about the plate tectonics revolution is that as the data came in—much of it collected by “fixist” geophysicists with the US Navy—the scientists rapidly and eagerly changed their minds, and a new consensus emerged in the space of a few decades. This belies the frequent accusation that scientists are conformists who stick to conservative topics just so that they can get funding. In fact, nothing attracts scientists’ attention like novelty and the hint of a new paradigm being born. Richard Alley, as always, expresses this with verve.

        https://critical-angle.net/2015/11/06/consensus-on-plate-tectonics-and-climate-science/

        The evidence that put continental drift into the forefront came from the fixists themselves.

        Sharpshooting stories like Cinq-Mars’ doesn’t get you any brownie points either:

        [I]n 2012, Lauriane Bourgeon, a doctoral candidate in anthropology at the Université de Montréal, decided to take a new look. She began microscopically examining 36,000 bone fragments that Cinq-Mars and his team had excavated. Archaeologists who specialized in the study of old animal bones had developed six criteria for the identification of human cut marks, such as the precise shape of the incision and its trajectory. Bourgeon only accepted a mark as evidence of human butchery if it met all six criteria.

        In two years of intensive work, Bourgeon identified human butchering marks on 15 bones from Bluefish Caves. She then took samples from six and sent them off for radiocarbon dating: The results showed that the oldest dated to 24,000 years ago—confirming Cinq-Mars’s original contention. Bourgeon now plans to write about two other key objects that Cinq-Mars found at Bluefish Caves: The mammoth bone flake and the worked bone core it came from. She is not ready to divulge the results of her analysis, but based on her published evidence, she describes Bluefish Caves as “the oldest-known archaeological site in North America.”

        http://www.smithsonianmag.com/science-nature/jacques-cinq-mars-bluefish-caves-scientific-progress-180962410

        Your pre-notion of evidence is getting the better of your judgement, Javier, and your Galileo gambit is just too obvious.

        May you one day open one book on the philosophy of science. This should provide you enough evidence to put your prejudices against philosophers to rest. At the very least it should be enough to make you see that you’re not playing home right now.

        ***

        > Leif Svalgaard, personal communication.

        Thank you for confirming that you were simply handwaving.

      • the scientists rapidly and eagerly changed their minds, and a new consensus emerged in the space of a few decades.

        Since when a few decades is rapidly?

        Nothing of what you say changes anything of what I have said about both Wegener and Cinq-Mars. Science does get it wrong from time to time, and when it does it is often for ignoring the evidence that contradicts the consensus.

        As I have no doubt about the honesty of the great majority of scientists. I am sure they are perfectly capable of getting the evidence that will demonstrate that the Co2 hypothesis, as currently formulated, cannot be correct.

        you were simply handwaving.

        No, I am not. That is the status of the situation whether you believe it or not. I am not going to look for quotes from multiple papers just because you ask. Specially because you ask. Read science instead of practicing philosophy.

      • > Nothing of what you say changes anything of what I have said

        Which kinda shows that judging evidence isn’t always as obvious as you portray it, dear Javier. To repeat the bits earlier emphasized, Cinq Mars’ hypothesis has been vindicated (a) after his evidence was *reanalyzed* (b) with newer instruments and (c) stricter evaluation standards. This reanalysis has then been (d) double-checked using cross-dating techniques. Finally, this reanalysis (e) corroborated the evidence from other sites.

        In other words, evidence is hard, even for the past.

        ***

        > I am not going to look for quotes from multiple papers just because you ask.

        That’s exactly what handwaving is.

        And thus our evidence specialist can’t even substantiate his handwaved claim about a whole discipline. No, wait. Make that two communities.

        ***

        > Since when a few decades is rapidly?

        Since science advances one funeral at a time, which means since forever.

        ***

        > I am sure they are perfectly capable of getting the evidence that will demonstrate that the Co2 hypothesis, as currently formulated, cannot be correct.

        Getting that evidence first would be a better idea than telling self-serving stories or armwaving charts and calling that evidence.

    • Willard: evidence without understanding is empty, and understanding without evidence is blind.

      Evidence without understanding is a step forward. “Understanding” without evidence is delusion.

      • > “Understanding” without evidence is delusion.

        Like Wegener’s or Darwin’s dangerous ideas, no doubt.

      • Willard: Like Wegener’s or Darwin’s dangerous ideas, no doubt.

        They had evidence.

      • The understanding before Wegener and Darwin was not based on evidence, but on some kind of conservative thinking, likewise before Copernicus or Hubble. Wegener, Copernicus, Hubble, and Darwin had ideas that could be supported by the later observed evidence. The analogy to that type of conservative thinking is those that still think trace gases or Man can’t influence climate. Those ideas should go the way of a fixed Creation, fixed continents, geocentric universe, and steady-state theory.

      • > They had evidence.

        Even creationnists have evidence. As soon as you can perceive something, you can accumulate evidence. Borgès tried to conceive beings void of any perceptual apparatus. But that was mere fantasy: infants void of stimuli don’t become delusory, they die.

        If evidence was truly what imposes itself to the inner eye, as its etymology suggests, contrarians wouldn’t have any room to wiggle. There would be no Contrarian Matrix. It’d be sad.

        If we don’t tolerate when a stones get thrown stones in a community, we’d have to close most if not all blogs, starting with this one. Cinq Mars’ experience was pre-Internet. I might get more aggression in a week than he did during his whole career.

      • > The understanding before Wegener and Darwin was not based on evidence, but on some kind of conservative thinking,

        As if pre-Darwin scientists were stoopid or different than Darwin himself. To take another famous name:

        Despite his limiting research bias, Linnaeus was a first class scientist. His most important contribution to science was his logical classification system for all living things which he proposed in his book Systema Naturae, first published in 1735. In this and subsequent works, he described plants and animals on the basis of physical appearance and method of reproduction. He classified them relative to each other according to the degree of their similarities. He used a binomial nomenclature click this icon to hear the preceding term pronounced in naming them. That is to say, organisms were given two Latin names–genus click this icon to hear the preceding term pronounced and species click this icon to hear the preceding term pronounced. Each genus could have many related species. Each genus was also part of larger categories of living things. This Linnaean system of classification is today the basis for naming and describing organisms in all fields of biology.

        http://anthro.palomar.edu/evolve/evolve_1.htm

        Everyone has biases, including Charles himself. But Darwin’s main edge was that he collected evidence most scientists could not dream up at the time. And of course Darwin’s theory had shortcomings, e.g. speciation. It still has.

        The problem seems to lie in the “evidence-based” concept. One does not simply do science by coming up with a theory for which evidence forms a foundational basis. That’s a priori crap – scientists come up with their theory to explain some phenomena. But that explanation never derives out of sheer necessity from the evidence itself.

        Moreover, scientific theories have problems. They seldom explain everything they need. That’s how they roll.

      • Willard: , and understanding without evidence is blind.

        Willard: As soon as you can perceive something, you can accumulate evidence.

        So you can, and so Wegener and Darwin did. Not everyone does, and certainly not about every subject. “Understanding” [i.e claims of understanding] without evidence is delusion; “blind” would be an improvement. With Kant it is never clear what he is writing about (e.g. the categories of human understanding, which are variously interpreted), or whether anything he writes of exists (e.g. the categories). What is a good example of understanding without evidence?

      • Willard: It’d be hard to have a delusion without any evidence whatsoever, Matt.

        That’s for a psychiatric diagnosis. Richard Dawkins believes he has written about a “God Delusion”, where evidence related to the existence of the supernatural is beyond description.

        Meanwhile, what is an example of understanding without evidence, in Kant’s sense?

      • If you task me to choose between the DSM and a zoologist turned into an intellectual entrepreneur known for his lack of due diligence in psychology, Matt, I hope you do not mind me for sticking with the mainstream scientific conception of delusion:

        Though Dawkins wasn’t a part of the interview process, and researchers didn’t ask about him, 48 of the 137 British scientists they spoke to mentioned Dawkins. Of those 48 that referenced him, 80 per cent said they thought that Dawkins misrepresents science and scientists in his books and public speeches, according to the study by Rice University, Texas.

        http://www.independent.co.uk/news/science/richard-dawkins-atheism-criticism-atheist-study-rice-university-science-scientists-a7389396.html

        While the ability to sell provocative rants may give some social fitness, it sometimes comes at the price of distorting concepts that are already quite robust.

      • Willard: While the ability to sell provocative rants may give some social fitness, it sometimes comes at the price of distorting concepts that are already quite robust.

        OK, so you don’t believe that “God is a delusion”. Is that because of the evidence in support of the existence of God: or because the belief is shared by the community?

        Meanwhile, could you provide an example of “understanding without evidence”, in Kant’s meaning?

      • > OK, so you don’t believe that “God is a delusion”.

        I rather shared the belief that teh Dawkins ain’t an authority in what counts as a delution, Matt, but thanks for probing my mind on an irrelevant topic. Most religious people I know (and I know more than you’d suspect) could not care less about the ontological question: Faith ain’t exactly a matter of belief. They do believe in love. That works for them.

        Do you believe in Love, Matt?

        ***

        > could you provide an example of “understanding without evidence”, in Kant’s meaning?

        I was rather referring to a Kant’s saying according to which thoughts without content are empty and intuitions without concepts were blind, but any analytic knowledge would do. Since there’s no need to buy any strict analytic/synthetic or a priori/a posteriori distinction, Kant’s synthetic a priori becomes mostly irrelevant. What could be of relevance for my point is that evidence is for the most part theory laden:

        Some evidence is produced by processes so convoluted that it’s hard to decide what, if anything has been observed. Consider functional magnetic resonance images (fMRI) of the brain decorated with colors to indicate magnitudes of electrical activity in different regions during the performance of a cognitive task. To produce these images, brief magnetic pulses are applied to the subject’s brain. The magnetic force coordinates the precessions of protons in hemoglobin and other bodily stuffs to make them emit radio signals strong enough for the equipment to respond to. When the magnetic force is relaxed, the signals from protons in highly oxygenated hemoglobin deteriorate at a detectably different rate than signals from blood that carries less oxygen. Elaborate algorithms are applied to radio signal records to estimate blood oxygen levels at the places from which the signals are calculated to have originated. There is good reason to believe that blood flowing just downstream from spiking neurons carries appreciably more oxygen than blood in the vicinity of resting neurons. Assumptions about the relevant spatial and temporal relations are used to estimate levels of electrical activity in small regions of the brain corresponding to pixels in the finished image. The results of all of these computations are used to assign the appropriate colors to pixels in a computer generated image of the brain. The role of the senses in fMRI data production is limited to such things as monitoring the equipment and keeping an eye on the subject. Their epistemic role is limited to discriminating the colors in the finished image, reading tables of numbers the computer used to assign them, and so on.

        https://plato.stanford.edu/entries/science-theory-observation/

      • Willard: I was rather referring to a Kant’s saying according to which thoughts without content are empty and intuitions without concepts were blind, but any analytic knowledge would do.

        That isn’t what you wrote.

        I rather shared the belief that teh Dawkins ain’t an authority in what counts as a delution, [sic]

        I was referring to the DSM definition that you cited. How does the God delusion fail to be a delusion under that definition? The DSM definition eliminates shared delusions

      • Willard: What could be of relevance for my point is that evidence is for the most part theory laden:

        So far, the concept of understanding without evidence has no exemplars. It is a null set.

      • > So far, the concept of understanding without evidence has no exemplars. It is a null set.

        I already gave you a way to produce an infinity: “about any analytic knowledge would do.” Unless you argue that the a priori can lend itself to evidence-based reasoning, it’d be hard to deny the possibility of theorical constructs that are evidence free.

        Rejecting that assumption (i.e. the analytic/synthetic distinction) only reinforces my point, since your knowledge basis still needs to include stuff like inferences. Evidence remains evidence of something, that something being, in science, the object of a theory or a conjecture. In other words, Javier can’t escape his theorical commitments by armwaving about evidence.

        And that’s the memo.

      • David Springer

        If you don’t believe in Creation then to be consistent you must believe that Love, like all your thoughts and actions, are mere coincidental coordination in a random dance of matter and energy.

        Ergo believing in Love is the same as believing in Creation.

      • Willard: Do you believe in Love, Matt?

        I think you give new meaning to the phrase reductio ad absurdum. No matter what the topic, once you enter the fray you keep on until you are writing nonsense.

      • Kant’s quip presumes that intuition and concept work hand in hand, Matt. That’s his very point. So I’m sure who’s the absurdist here.

        The same could very well be said of evidence and theory. How does that undermine my point exactly? That’s just a way to restate it.

        ***

        Oh, and you might like this:

        According to Paul van Buren, a Death of God theologian, the word God itself is “either meaningless or misleading”.[2] He contends that it is impossible to think about God. Van Buren says that

        “We cannot identify anything which will count for or against the truth of our statements concerning ‘God'”.[2]

        https://en.wikipedia.org/wiki/Christian_atheism

        The henchmen of atheism produced may very well have produced more manure than the horses upon which they figuratively ride.

      • Willard: Kant’s quip presumes that intuition and concept work hand in hand, Matt. That’s his very point.

        So you could have written something sensible, instead of what you wrote.

        How about this:Do you believe in Love, Matt? ? Do you have a sensible rendition of that absurdity?

      • Love is all you need, Matt. At least insofar as you go for the path of tge heart. God’s existence is the lesser concern of 97% of the religious people.

        You just got astray with a freaking figure of speech.

        If you accept that physical objects are conceptually imported into the situation as convenient intermediaries not by definition in terms of experience, but simply as irreducible posits comparable, epistemologically, to the gods of Homer, but in point of epistemological footing, the physical objects and the gods differ only in degree and not in kind, the whole Dawkins playbook falters. Both sorts of entities enter our conceptions only as cultural posits.

      • Willard: You just got astray with a freaking figure of speech.

        Maybe.

        This interchange might have been shorter if you had admitted at the start that it was only a “freaking figure of speech” instead of defending it.

        I prefer my interpretation: Evidence without understanding can be progress, as with the Balmer series. “Understanding” (e.g. claims or beliefs of understanding) without evidence is delusion, as in the belief of his followers that David Koresh was a messenger of God, or the occasional beliefs people have that they are impervious to bullets. There may indeed always be something that can be cited as “evidence”: I remember the Reverend William Sloan Coffin telling me that the “unmerited good” on Earth was evidence for the existence of God. I think a lot of people would not accept that as evidence for God, if you asked them to list the attributes of God. Dawkins does not prove that God is a delusion, anymore than it can be proved that the Pons-Fleischman cold fusion apparatus does not work; all he shows is that, for any listing of the attributes of God, the evidence is slim to contradictory.

      • > This interchange might have been shorter if you had admitted at the start that it was only a “freaking figure of speech” instead of defending it

        In return, Matt, please consider how asking your leading question and peddling Dawkins crap worked for you. I fell for your ontological baits. It took me a while to get that these baits concealed a complete misunderstanding of my point.

      • Willard: these baits concealed a complete misunderstanding of my point.

        No. You wrote a complete misrepresentation of your point. You thought that you wrote something trenchant and sharp, but instead it was empty.

  25. Javier,

    I have at last found time to read this post. Thank you. It is clearly explained and very interesting and thought provoking.

    I have some questions:

    1. What is the closest time spacing of temperature readings from the Greenland ice cores?

    2. Figure 49 is very interesting although I understand (perhaps misunderstand) there is little support for the galactic forcing explanation for the 150 Ma cycle of ice ages.

    3. Why did you not mention the locations of continents, ocean gateways, and their consequent effect on ocean currents and the transfer of heat from tropics to polar regions as a cause of hothouse and coldhouse periods?

    Comments:

    The global warming that has taken place during the last 350 years cannot be separated from the previous cooling without losing part of its context.

    Important implications for attribution of human contribution to the current warm period.

    each period of warming during the descent to the next glacial stage should be more intense than the previous ones, as climatic variability increases outside the warm conditions of an interglacial climatic optimum.

    Human- caused GHG emissions may be more beneficial than damaging if they can delay or reduced the magnitude of the next abrupt cooling event.

    6) The Neoglacial has been a period of progressive cooling, increasing aridity, and advancing glaciers, delimited by the 5.2 kyr event at its beginning and the Little Ice Age at its end.

    Likewise, human caused GHG emissions may be beneficial in delaying or reducing the damage in the next abrupt cooling event.

    Pity we never see the risk analysis showing the benefits of GHG emissions.

    • I recall there’s a Greenland ice core data set that claims 20 year resolution.

    • The crf is pretty solid. Someone did a hack “debunking” hit job. They used an invalid computer model to cherry pick data to make the relationship go away. They used a model of a two arm spiral galaxy to calculate period and threw out samples that didn’t agree, the milkyway is actually 3 armed, kind of two rotating around a 3rd out of plane. Shaviv calculated crf empirically using meteors and impact dates.

  26. The Carboniferous-Permian ice age lasted about 60 Ma.

    The current ice age has lasted about 10 Ma so far (perhaps 35 Ma depending how we define the start). So, if it will take as long to pass through the galactic spiral arms this time as it did 300 Ma ago, we have 25 to 50 Ma until we start to get out of the current ice age. As Ian Plimer says “don’t wait up”.

  27. Javier what is your climate prediction for the next 20 years ? Based on what factors ?

    That is what matters and is relevant.

    • what is your climate prediction for the next 20 years?

      I am not in the prediction business. Prediction is very difficult, especially about the future. All I can do is give my informed opinion about what position we occupy in the climatic cycles and what effect CO2 might be having by comparing what should be happening and what is happening. With that everybody can form their own opinion. I’ll do that in the last article in the series.

      But the climatic cycles are only a part of climate change and if something we should have learned from the last 20 years is that nobody on the planet has the capability of predicting climate. That obviously includes you.

  28. Javier , I expect one or two major volcanic eruptions within the next 3 years and yes associated with the very low solar activity.

    And what is frustrating is if it happens you and many others are going to say the cooling how ever much it may be is due to volcanic activity independent of the sun.
    I on the other hand have stated this as part of the reason why global cooling may occur going forward.

    So if major volcanic activity should pick up during this very low solar period of time like it did during the Dalton Solar Minimum it will not be recognized as a solar/climate link although would be n my opinion.

    What I and others in agreement are up against is going to be never ending denial no matter what takes place , but what matters is what the climate does from here going forward and it is going cool due to one or more of the solar/climate connections I have talked about in my previous post.

    • The below pingback is dead for me.

    • I expect one or two major volcanic eruptions within the next 3 years and yes associated with the very low solar activity.

      I you can refine a little your volcanic eruption predicting skills I am sure you can make a lot of money. After you nail the first two you can charge anything for your predictions.

      • That is how I feel Javier. Maybe I will be wrong but I have made a prediction unlike others who talk climate but never address the most important issue which is what will the climate be doing over the next 20 years and why.

        Javier nobody can predict volcanic activity but data suggest that it is more likely during prolonged solar minimums at least the major eruptions.

      • data suggests volcanic activity is more likely during prolonged solar minimums

        No. Data does not suggest that. We have volcanic sulfate data from Greenland and Antarctica, and a solar activity record that expands 50,000 years. Every study claiming a relationship between solar activity and volcanic activity is limited to the LIA. When there is thousands of years of records and yet people make claims about a small part, that is highly suspicious to say the least.

        I bothered enough to make a graph relating volcanic activity during the past 50,000 years. It doesn’t match solar activity, and it doesn’t match temperatures. The only obvious match is what is expected: Glacial isostatic adjustment. When ice-sheets melt, you get a lot of volcanic activity, because the crust moves.

      • Have you considered the possibility that the increased volcanic activity during the LIA was due to expansion and contraction of continental ice? In a short span glaciers globally grew to their highest Holocene extent, and then rather quickly in geological terms melted back to their minimal Neoglacial extent. That surely has to shake the crust. Sincerely I don’t see solar wind having much effect on volcanoes.

  29. Javier, thank you for the essay.

  30. The text related to Fig44 is very interesting. It relates to 3200bce (~5.2ky bp). But there is one item missing. Megalithic calendars that have to be axially aligned to equinox sunrise point on horizon experienced a rotation of about 47deg from before to after. An earlier similar event occurred at ~5200bce. Meaning climate change is a secondary effect; the primary is something else, and cataclysmic, around the Med at least.

    In link here below, other proxies show the two events quite clearly. https://melitamegalithic.wordpress.com/2017/02/24/blog-post-title-2/

  31. Javier, thank you for your essay. Thank you also for your responses to the comments. It gives me hope that science has not been completely suffocated by alarmism.

      • Peter Lang

        Javier,

        I asked three questions:

        You have answered one by referring me to our previous comments – about 150 Ma cycle controlled related to galactic spiral arms, and tectonic plate locations.

        If you know the answer to my Q1, could you please answer it. My reason for asking is that some time ago I recall reading somewhere that data was being extracted from at least one Greenland ice core at times scales down to several per year; quantity and chemical composition of dust from Siberia was being analysed and interpreted. I don’t know if this is correct, and was hoping you or someone else might know and, if possible, give me a link.

        Regarding the 150 Ma cycle for geologic ice ages (or coldhouse phases), I am taking this in, but not yet convinced for two reasons.

        First, the peak of the Carboniferous-Permian ice age occurs 50 Ma after the peak of the galactic cosmic ray flux during a long period of declining cosmic ray flux. This is inconsistent with the alignment with 35 Ma delay of the other ice ages and the peaks of the cosmic ray flux. This needs explanation because the Carboniferous-Permian was the next coldest (after the current one) of the ice ages over the past 650 Ma

        Source: Nir Shaviv, The Milky Way Galaxy’s Spiral Arms and Ice-Age Epochs and the Cosmic Ray Connection http://www.sciencebits.com/ice-ages

        Second: the ice ages over the past billion years don’t appear to be spaced on a regular 150 Ma cycle:

        Glacial period From To Duration
        Quarternary 35 0 35
        Carboniferous–Permian 360 260 100
        Ordovician–Silurian 460 430 30
        Ediacaran Baykonurian
        547 541.5 5.5
        Ediacaran Gaskiers
        579.88 579.63 0.25
        Cryogenian Marinoan 650 635 15
        Cryogenian Sturtian 717 660 57
        Cryogenian Kaigas 850 736 114
        Source: https://en.wikipedia.org/wiki/Sturtian_glaciation

  32. “Different numeric tests, such as an analysis of the Lyapunov exponents (Ostryakov and Usoskin 1990b; Mundt et al. 1991; Kremliovsky 1995; Sello 2000), Kolmogorov entropy (Carbonell et al. 1994; Sello 2000) and Hurst exponent (Ruzmaikin et al. 1994; Oliver and Ballester 1998), confirm the chaotic/stochastic nature of the solar-activity time evolution (see, e.g., a review by Panchev and Tsekov 2007).” https://link.springer.com/article/10.1007/s41116-017-0006-9#Sec15

    A very good review – btw.

    ENSO switched from La Nina to El Nino around the turn of the 20th century.
    La Nina dominance before had a beat of around 6-7 yr, while El Nino dominance since has around a 2-5 yr beat. It suggests that ENSO is a stochastically forced resonant system. The more recent suggestion is that it is triggered by changes in polar surface pressure which modulate wind and ocean currents in both the north and south hemispheres. Negative SAM and NAM facilitate upwelling in the eastern pacific. So is there a solar signal in the evolution of ENSO?

    Moy et al (2002) present the record of sedimentation shown above which is strongly influenced by ENSO variability. It is based on the presence of greater and less red sediment in a lake core. More sedimentation is associated with El Niño. It has continuous high resolution coverage over 12,000 years. It shows periods of high and low ENSO activity alternating with a period of about 2,000 years. There was a shift from La Niña dominance to El Niño dominance that was identified by Tsonis 2009 as a chaotic bifurcation – and is associated with the drying of the Sahel. The sun is the isotope record shifted to a low activity mode. There is a period around 3,500 years ago of high ENSO activity associated with the demise of the Minoan civilisation (Tsonis et al, 2010). Red intensity was in excess of 200 – in contrast the red intensity in 97/98 was 99.

    So there is a suggestion of climate effects at the quasi-periodic 2000 to 2400 year scale. But there is no one to one correspondence with a stochastically resonant climate system. And there is still no sense in which the future evolution of the solar activity can be confidently predicted. Despite the cyclomania of Javier and most of the denizens it seems.

  33. Interesting the solar system’s position in the galaxy affects climate. Can anyone point out to me a reason that this may be so?

    • Hi Dave,

      Several possible causes are being investigated.

      One would be the irregular distribution of the sources of galactic cosmic radiation so some areas appear to have a higher level of cosmic rays that could affect climate.

      Another one, more interesting in my opinion, is the irregular distribution of galactic clouds of different densities. Take a look at this:
      https://jila.colorado.edu/news-highlights/cloud-tripping-through-milky-way

      In less than 5000 years the earth should be in G cloud.

      The effect can be pretty drastic. According to this article:
      Linsky, J. L., Redfield, S., & Schwarz, M. (2016, November). Visualizing the three-dimensional structure of the local interstellar medium and possible physical causes for this structure. In Journal of Physics: Conference Series (Vol. 767, No. 1, p. 012016). IOP Publishing.
      http://iopscience.iop.org/article/10.1088/1742-6596/767/1/012016/pdf
      “Müller et al. (2006) [8] calculated the location of the termination shock, heliopause, and bow shock for a wide range of interstellar densities, temperatures, and flow velocities that the heliosphere would see during its past and future trajectory through the inhomogeneous LISM. For example, the passage of the heliosphere through a cloud with a neutral hydrogen density of 11 cm−3 rather than the present value of about 0.2 cm−3 would shrink the termination shock from about 90 AU in the upwind direction to only 14 AU.”
      It remains to be determined if this conjecture can find support from evidence, but a priori such large change looks capable of bringing about an ice age size climate change if sustained for millions of years.

      In any case it appears that the galactic position could actually affect the very long term climate of the earth. It might take millions of years to demonstrate it, though. Or perhaps one day we will be able to map the galactic clouds and calculate their past positions and evolution, together with the path of the solar system. It doesn’t look easy.

  34. Thanks again Javier – I love figure 45!
    Chaotic dynamics give rise to spontaneous nonlinear pattern formation, than this is true in the time dimension as well as that of space.
    So in a dissipative-chaotic system like climate, it is not surprising that the time wavetrain of climate status looked at from numerous metrics, will show emergent periodic structure and complexity. It would be extremely odd an unnatural for it to look uniform – although this is what AGW narrative requires.

  35. Understandably, tenuous proxy-reconstructions are the only window we have on multi-millennial-scale climate variations. But, even after making allowances for all the vagaries of paleo data, it’s difficult to see great coherence between the various time series shown in Figure 46.

    Furthermore, so-called “abrupt changes” are not even particularly striking non-stationarities, let alone discrete jumps, in the respective proxy records. They’re pretty much what the experienced eye expects to see in wide-band stochastic processes with multiple oscillatory components of various bandwidths–even in the absence of emergent phenomena. And, on a human time-scale, the climatic changes during the recent Holocene are dominated by multi-decadal oscillations, as seen in power spectrum of the 20yr rate-of-change of Greenland GISP2 ice-core δ18O:
    http://s1188.photobucket.com/user/skygram/media/graph2.jpg.html?o=1

    • I agree that the term abrupt is not properly defined and entirely depends on the temporal scale. For example most climate scientists think that the 20th century warming has been abrupt, and I tend to agree. However from personal experience I haven’t noticed anything abrupt. I have felt the warming from the early 70’s to the late 90’s obviously, essentially for the winters, but not in an abrupt way. Even 2016 the year of record warm felt just like a particularly warm summer followed by a particularly nice winter, but nothing extraordinary. And that was a +1°C anomaly! We had more trouble with the 2003 heat wave over Southern Europe and that was not a particularly warm year.

      Regarding the coherence of climate proxies time series for multi-millennial-scale climate variations, I will have my own take in future articles discussing the different periodicities. It is a complicated issue, not easily amenable to frequency analysis, given the irregular nature of the data, but I think it will become much clearer when properly presented.

      • It is a complicated issue, not easily amenable to frequency analysis, given the irregular nature of the data

        How true! It’s precisely the customary lack of sufficiently-frequently periodically-sampled data (which produces aliasing of high frequencies into false low frequencies) that makes paleo time-series notoriously unreliable. In this connection, it’s worth noting that the sampling frequency of GISP2 data (1/20yrs) is by far the highest of the proxy series in Figure 46; that is also the series that exhibits the least multi-millennial variance.

        BTW, on both mathematical and physical grounds, there is even less basis for expecting truly abrupt changes in global average temperatures than in local ones. While shifting positions of various oceanic currents and atmospheric fronts can suddenly bring a particular location under a different climatic regime, there is no well-established mechanism of the entire planet experiencing analogous boundary crossings. Major changes in global albedo move at a glacial pace. On a planetary basis, we thus have a high-inertia, energy-conserving thermodynamic system.

      • That depends what you consider “well-established mechanisms.” Boundary crossings that can cause climatic shifts capable of affecting most of the planet or very large regions of it have been proposed. One of them would be the change from La Niña dominated periods to El Niño ones (or the opposite). Another would be the entering of the North Atlantic into persistent negative conditions, that appears to affect most of the Northern Hemisphere from the Siberian High to Santa Barbara precipitation.

      • A well-established mechanism is one that, starting with first principles, quantitatively explains some carefully observed phenomenon unequivocally.

        While the various stages of the ENSO phenomenon are qualitatively described in terms of the waxing and waning of trade winds and the Walker Circulation, there is no quantitative theory that truly nails the problem from first principles. It’s origins and operation, along with that of multi-decadal SST cycles, remain somewhat of a scientific conundrum. They’re certainly not, however, problems of simple boundary crossings to which I had alluded. Unlike with purely thermodynamic problems, we are dealing potentially with the full panoply of behavior of second-order dynamical systems.

        Although the mathematical foundations of nonlinear dynamical oceanography are well-developed (see Dijkstra’s monograph of that title) and there are many ideas afloat concerning “abrupt climate change’ (see http://academic.evergreen.edu/z/zita/articles/climate/AbruptChange03.pdffor a more accessible summary), what has not been developed so far is a comprehensive physical theory of climate that finds ample empirical validation. The most reliable empirical evidence available fails to shows anything that can’t be accounted for by quite ordinary, smooth changes of a quasi-gaussian stochastic process.

      • We agree. Climate science has been described by Dr. Curry as a wicked problem. We are very far from being able to go from first principles to a comprehensive physical understanding if we are ever going to reach that point. The failure of climate models to adequately reproduce what the climate is doing is a demonstration that our understanding is woefully inadequate.

        However Alley et al., 2003 defend that “Even a slow forcing can trigger an abrupt change, and the forcing may be chaotic and thus undetectably small.” There is some evidence that I will be presenting in the next article, that this could be the case, and small and slow forcing changes could be responsible for climate changes that cannot be attributed to stochastic processes, given their regularity.

      • The word “for” needs to be separated from the given link for it to work.
        http://academic.evergreen.edu/z/zita/articles/climate/AbruptChange03.pdf

      • “… quasi-gaussian stochastic process.” … is just a sad little example of twaddle.

        Recent scientific evidence shows that major and widespread climate changes have occurred with startling speed. For example, roughly half the north Atlantic warming since the last ice age was achieved in only a decade, and it was accompanied by significant climatic changes across most of the globe. Similar events, including local warmings as large as 16°C, occurred repeatedly during the slide into and climb out of the last ice age. Human civilizations arose after those extreme, global ice-age climate jumps. Severe droughts and other regional climate events during the current warm period have shown similar tendencies of abrupt onset and great persistence, often with adverse effects on societies.

        Abrupt climate changes were especially common when the climate system was being forced to change most rapidly. Thus, greenhouse warming and other human alterations of the earth system may increase the possibility of large, abrupt, and unwelcome regional or global climatic events. The abrupt changes of the past are not fully explained yet, and climate models typically underestimate the size, speed, and extent of those changes. Hence, future abrupt changes cannot be predicted with confidence, and climate surprises are to be expected.

        The new paradigm of an abruptly changing climatic system has been well established by research over the last decade, but this new thinking is little known and scarcely appreciated in the wider community of natural and social scientists and policy-makers. At present, there is no plan for
        improving our understanding of the issue, no research priorities have been identified, and no policy-making body is addressing the many concerns raised by the potential for abrupt climate change. Given these gaps, the US Global Change Research Program asked the National Research Council to establish the Committee on Abrupt Climate Change and charged the group to describe the current state of knowledge in the field and recommend ways to fill in the knowledge gaps.” https://www.nap.edu/read/10136/chapter/2

        Abrupt climate change is entirely deterministic and pretty much the scientific consensus. Dismissing it on the basis of a “… quasi-gaussian stochastic process” is utter nonsense.

      • Javier:

        I look forward to your forthcoming presentation, which I hope will recognize
        that the planetary climate system is one forced by energy inputs from OUTSIDE and not by intrinsic INTERNAL dynamics.

        Alas, there’s not a qualified geophysical dynamicist among the authors of
        the paper that I linked. Alley is a glaciologist, whose singular
        contribution, to my mind, is obtaining the relatively alias-free GISP2
        isotope record–a rarity in paleo-climatic studies. Because it showed the
        abrupt changes of the Younger Dryas, which corroborated other paleo data, it became the “paradigm shifting” basis for largely unsupported,academic conjectures about “abrupt climate change.” His uncritical acceptance elsewhere of CO2 as the climate “control knob,” along with unrealistic “conveyor belt” shut-down and of internal jump-resonance explanations of the singular Younger Dryas period leaves much to be desired in terms of scientific rigor.

        Nevertheless, the salutary aspect of the GISP 2 data is the clear indication
        it provides of a gentle, truly secular cooling trend since the Holocene optimum, overlain by weakly stationary, strongly structured, quasi-Gaussian stochastic variations whose ordinate distribution and power-spectrum both diverge from anything resembling a Poisson process of abrupt jumps. In other words, there’s no indication of a nonlinear system exhibiting jump resonance as an intrinsic response characteristic.

      • > there’s not a qualified geophysical dynamicist among the authors of
        the paper that I linked.

        What would be an example of such qualified geophysical dynamicist. JohnS?

  36. Reblogged this on 4timesayear's Blog.

  37. “What defines a climate change as abrupt? Technically, an abrupt climate change occurs when the climate system is forced to cross some threshold, triggering a transition to a new state at a rate determined by the climate system itself and faster than the cause. Chaotic processes in the climate system may allow the cause of such an abrupt climate change to be undetectably small.” https://www.nap.edu/read/10136/chapter/3#14

    Whatever scale the cause.

  38. “This paper provides an update to an earlier work that showed specific changes in the aggregate time evolution of major Northern Hemispheric atmospheric and oceanic modes of variability serve as a harbinger of climate shifts. Specifically, when the major modes of Northern Hemisphere climate variability are synchronized, or resonate, and the coupling between those modes simultaneously increases, the climate system appears to be thrown into a new state, marked by a break in the global mean temperature trend and in the character of El Niño/Southern Oscillation variability.” http://onlinelibrary.wiley.com/doi/10.1029/2008GL037022/full

    You can’t have a step change in temperature – it depends on the accumulation of energy in the system. You can get abrupt change in ocean and atmospheric regimes that change the global energy budget with ice, cloud, dust and vegetation feedbacks. So I’m not really surprised Javier hasn’t noticed it.

    • You can’t have a step change in temperature? A step change is exactly what the satellites show. Flat 1978-1997, then flat again after the big ENSO, but a small step up, presumably due to that ENSO..

      • Atmospheric temps are about 4% of the global energy content. It responds quickly to volcanoes, ENSO and other factors. Over analyzing the short tropospheric record is not the point. The oceans are the main game.

        .

      • Atmospheric temperature is the focal point of the climate change issue. There is no known explanation of the ENSO coincident step change. So I do not see this as over analysis.

      • A step change is exactly what the satellites show… presumably due to that ENSO.

        Clearly temperatures do not go up or down at uniform rates. However there is no evidence that ENSO is related to the warming.
        Some people think that the warming is related to El Niño.
        Almost nobody thinks the more likely explanation that the warming is related to the strong La Niña after the El Niño.
        Alternatively ENSO might be unrelated to the warming.

  39. Javier,

    Can you please give a link to Figure 49. I haven’t found it on Knownuthing Game over https://www.rankia.com/blog/game-over/3113785-ciclos-glaciales

  40. Javier,

    In the discussion the previous threads you linked to instead of answering my questions on this thread, I had asked you repeatedly if you could provide a link to an authoritative, clear, simple chart of GMST versus time over the Phanerozoic Eon that is better than Scotese’s 2015 chart.

    My question was because you had posted a chart earlier that it appears you had made by turning Veizer dO18 chart upside down, changing the units from dO18 to temp C anomaly with range -8C to +12C (see below), and adding “mass extinction events” at abrupt cold events but did not include the equivalent for warm events. I later discovered that the original Veiser dO18 chart was for tropical temperatures only, not GMST, so the Temp C anomaly added (by you?) was not correct. It appears the changes to the charts were not done by Veiger and were incorrect and highly misleading. You never mentioned andy of this and never gave the reference to where the chart was published.

    It would help if you could provide straight, clear, succinct, honest answers to questions that are asking for information.

  41. I just found this info on the Gaskiers Glaciation and the 90 km diameter meteorite impact at around the same time (about 590 Mya) ( I am interested in this because I worked in the area in 1967-68).
    580 Mya dates the meteor strike at the start of the Gaskiers ice age (579.88 to 579.63 Ma). The duration of the ice age was just 250,000 years (579.88 to 579.63 Ma). That’s unusually short for an ice age.

    Extract from Abstract on it

    “The ice-rafted material in the Bunyeroo Formation only has been found510 m stratigraphically below and above a horizon of dacitic ejecta related to the 90 km diameter Acraman impact structure in the Mesoproterozoic Gawler Range Volcanics 300 km to the west. Furthermore, till pellets have been identified 4.4 to 68 m below distal Acraman ejecta in the Dey Dey Mudstone4500 km northwest of the impact site. The Acraman impact took place at a low paleolatitude (*12.58) and would have adversely affected the global environment. The stratigraphic observations imply, however, that the impact occurred during, but did not trigger, a cold interval marked by sea ice and glacial ice, although the temporal relationship with Ediacaran glaciations elsewhere in Australia and on other continents is unclear. Release from the combined environmental stresses of a frigid, glacial climate near sea-level and a major impact in low latitudes may have been a factor influencing subsequent Ediacaran biotic evolution.”

    V. A. GOSTIN*, D. M. MCKIRDY, L. J. WEBSTER AND G. E. WILLIAMS (2010)
    Ediacaran ice-rafting and coeval asteroid impact, South Australia: insights into the terminal Proterozoic environment.
    https://www.monash.edu/__data/assets/pdf_file/0003/75522/gostin-2010-ediacaran.pdf

  42. When a nonlinear-chaotic system (i.e. almost anything in nature) is weakly periodically forced by not one but several forcing periodicities, then it might be better to analyse it as a nonlinear Helmholz response .

  43. There is one way that the planet warms – if energy in is greater than energy out.

    Δ(W&H) = energy in – energy out

    This is the ‘thermodynamics’ referred
    to that don’t abruptly change – the 1st law of thermodynamics. Although true it is not the basis of climate variability. The latter derives from – mostly – changes in energy out that caused by internal climate dynamics. Some of that in response to small solar – including UV – and orbital variability.

    In the words of Michael Ghil (2013) the ‘global climate system is composed of a number of subsystems – atmosphere, biosphere, cryosphere, hydrosphere and lithosphere – each of which has distinct characteristic times, from days and weeks to centuries and millennia. Each subsystem, moreover, has its own internal variability, all other things being constant, over a fairly broad range of time scales. These ranges overlap between one subsystem and another. The interactions between the subsystems thus give rise to climate variability on all time scales.’

    Moreover the physical evidence – on inter-annual to millennial scales – is for abrupt change between climate regimes and persistence of regimes. This is a property of the broad class of nonlinear, complex, dynamic systems. The changes in ocean and atmospheric regimes modulate the energy budget of the planet on all scales.

    “Climate forcing results in an imbalance in the TOA radiation budget that has direct implications for global climate, but the large natural variability in the Earth’s radiation budget due to fluctuations in atmospheric and ocean dynamics complicates this picture.” https://link.springer.com/article/10.1007/s10712-012-9175-1

    The complications seem more interesting than any mooted greenhouse gas energy imbalance. There are much larger influences on ocean warming and cooling and the thermal inertia argument seems therefore moot.

    There is no one to one correspondence between weak quasi-periodic ‘solar cycles’ and climate regimes. At best – if there is a feasible mechanism – solar variability biases the system to specific states.

    Cyclomania is a very old fashioned science – not one that can be all that persuasive. There may a tenuous link – the Hale cycle to Pacific states for instance – but demonstrating this in any conclusive way is elusive.

    • Cyclomania is a very old fashioned science

      As old as cyclophobia. The discussion if climate variations take place in cycles or not is as old as humankind, and is behind the building of calendars. This discussion has always been won by cyclophilics. By the end of 19th century cyclophobics were trying to discredit the idea that climate could change in cycles due to poor evidence and poor records. They were thoroughly defeated when Milankovitch theory was supported by evidence in the early 1970s. Instead of admitting defeat, cyclophobics regrouped and said “OK, we accept Milankovitch cycles, but all the rest of climate cycles we don’t.” I guess they don’t tire of being wrong.

      • Orbital dynamics are one of the small control variables that influence the system to one state or the other. To more or less ice in the case of glacials and interglacials. There we have an internal mechanism that is obvious if not understood in full detail. At best it is a broad regularity with chaos within chaos. The theory suggests that the system is pushed by greenhouse gas changes and warming – as well as solar intensity and Earth orbital dynamics – past a threshold at which stage the components start to interact chaotically in multiple and changing negative and positive feedbacks – as tremendous energies cascade through powerful subsystems. Some of these changes have a regularity within broad limits and the planet responds with a broad regularity in changes of ice, cloud, Atlantic thermohaline circulation and ocean and atmospheric circulation.

        Cyclomania without actual physical mechanisms is searching for patterns within patterns. It is usually misguided nonsense.

      • Cyclomania without actual physical mechanisms is searching for patterns within patterns.

        You just don’t learn from history. The glacial cycle didn’t have a mechanism until Milankovitch arrived, and it was not less real because of lack of mechanism. That something, for which there is clear evidence, doesn’t have a mechanism only speaks of our ignorance.

        You probably think we know a lot. We don’t. It is expected that in a few hundred years people will think how dumb and ignorant we were.

        The theory suggests…

        Theories don’t suggest anything. Theories explain, but whether the theory is correct or not remains to be seen. That we have an explanation doesn’t mean that it is the right explanation. It is always best to stick to the empirical evidence, and the evidence shows very clear regularities in the climate. For some we have a good explanation and for others we don’t. That doesn’t make them less real.

      • “The climate system has jumped from one mode of operation to another in the past. We are trying to understand how the earth’s climate system is engineered, so we can understand what it takes to trigger mode switches. Until we do, we cannot make good predictions about future climate change… Over the last several hundred thousand years, climate change has come mainly in discrete jumps that appear to be related to changes in the mode of thermohaline circulation. We place strong emphasis on using isotopes as a means to understand physical mixing and chemical cycling in the ocean, and the climate history as recorded in marine sediments.” Wally Broecker

        Orbital variations are not technically the cause of glacials/interglacials. They are at best a control variable.

        A thing I dislike intensely is quibbling about words. The broader theory of dynamical complexity says that chaotic systems exhibit characterisitc behaviours – among these abrupt change and regime persistence. The diagnoses for chaos is that the systems exhibit these behaviours. Chaos theory suggests that small changes in control variables push the system past a threshold at which stage internal dynamics determine the evolution of the system. We can see these behaviours in climate at all scales.

        Chaos is one of the 3 great ideas of 20th century physics – along with relativity and quantum mechanics. It is undoubtedly true that climate is chaotic – something that doesn’t seem to click with old fashioned cyclomaniacs.

      • It is undoubtedly true that climate is chaotic

        So you say without any evidence. But the most salient climatic feature of the Pleistocene, the glacial cycle, is not chaotic.
        Tzedakis, P. C., et al. “A simple rule to determine which insolation cycles lead to interglacials.” Nature 542.7642 (2017): 427-432.
        http://eprints.esc.cam.ac.uk/3856/1/nature21364.pdf

        So if chaos does not explain the most salient feature of Pleistocene climate, how come you display such confidence that chaos can explain climate change?

        I tell you want. Since you have such low opinion of this old fashioned cyclomaniac, why don’t you stop posting comments in my articles. Alternatively I will stop answering them.

      • There is a world of evidence – and one wonders how a ‘simple rule’ negates this. Not understanding or even reading the dozens of eminent sources I have provided is a different matter.

      • Geoff Sherrington

        Javier wrote to Ellison ” why don’t you stop posting comments in my articles”

        Javier, I second that. Ellison, you are now tiresome and repetitive and frequently ot. Give it a break, huh?

        Thanks Geoff.

      • I will comment where and how I like regardless of Geoff’s well intensioned advice. Everything I said is entirely on topic – if it is information that goes well beyond the grasp of most blogospheric climate warriors. That Javier objects to a better paradigm of global change is neither here nor there either.

        The US National Academy of Sciences (NAS) defined abrupt climate change as a new climate paradigm as long ago as 2002. A paradigm in the scientific sense is a theory that explains observations. A new science paradigm is one that better explains data – in this case climate data – than the old theory. The new theory says that climate change occurs as discrete jumps in the system. Climate is more like a kaleidoscope – shake it up and a new pattern emerges – than a control knob with a linear gain.

        https://www.nap.edu/read/10136/chapter/1

        The NAS is just one of the sources I provide.

        I just read Geoff’s comment on the oceans not expanding. I don’t think there is a comment from him that I have seen that isn’t nonsense. But attempting to close down dissenting voices is the bigger problem. It is why this site has become such an echo chamber of non-scientific denier narrative.

      • R Ellison

        Your argument of “where’s your mechanism” and “the models dont’ predict it” was identified as a cognitive fallacy by Aristotle. He called it “argumentum ad ignorantium”. Very well suited to your muddle headed mix of appeal to authority and immature label-slinging. Perhaps better to also call it “argumentum ad confusiorum”.

        Can you let us into a secret? – it will be safe with us. When you are admitted into the ranks of the climate believers, is it true that the secret initiation ritual involves the warmist priest or a colleague plunging a knitting needle into your forebrain and stirring vigorously for a minute or two? You’ll feel better if you share this with us.

      • This is the fallacy of false binaries. If I do echo the idiocies of climate warriors then I must be an alarmist. It is as well an incorrect use of the appeal to authority principle. Where the appeal to authority is to hundreds of authoritative sources – it is not an appeal to a dubious authority implied by the phrase.

        It is also hypocrisy of the first order – immature labeling?

      • Robert
        Apologies for my immature comments. I misunderstood your position, which on further reading I find to be one with which I largely agree. My bad.

  44. Following the announcement by President Trump, I ask: Is all this relevant? Present day Climate change debate only relates to closing it down – if you refer to the activists. Please correct me if I am wrong. Let us keep our minds to 1750 to present day. Global warming is one of the two components of climate change. How many thermometers were there globally in 1750, considering Fahrenheit invented the thermometer in 1715? Second component relates to the presence of carbon dioxide in the atmosphere in 1750. How did they measured it then? All I know is that CO2 cannot be measured unless water vapour is removed from the air sample, but a device was patented in 1972 that side-lined this process. The statements relating to pre-industrial age are by a consensus within the scientific community to shut down any debate on the veracity of claims and also stopping other scientists from doing real research, or just toss in the towel and say we were wrong? People want facts because the ‘climate change industry’ costs us a lot of money.

  45. How is it that ice ages always start when CO2 warming is supposed to prevent ice ages? In any othe4 field of science this would be enough to falsify AGW.

  46. Always start when co2 is high.

    • In the paleo context 300 ppm is not high, which is why we have Ice Ages and lower sea levels now, and didn’t for most of the last 100 million years when CO2 levels have been higher. There is a clear connection to the evolution of GHG levels over millions of years.

      • Geoff Sherrington

        Jim D,
        Please examine the evidence.
        The bulk of mankind’s emission of CO2 to the air is since (say) 1950.
        If this had heated the oceans, they would have expanded.
        There is ample objective evidence that observed expansion is unseen when compared with preceding decades or, at best, hidden in the noise level.
        There is no accepted explanation why thermometer liquids have expanded anomalously 1950 to 2000, but the oceans have not.
        The evidence is very strong, to support the assertion that the oceans have not warmed to the extent predicted by GHG theory.
        Do you not agree?

        BTW, it is an interesting exercise to try to find what should be a developed, published metric, namely, the expected sea level rise for a one degree C rise in temperature. A cynic might conclude that it is an embarrassment and is therefore locked away, like the manic aunt in the upstairs attic.
        Do you have such a metric to tell to us?
        BTW2. If you counter that GHGs are heating the air (and moving thermometer fluids) but not the oceans (and hence not the expansion level) then you have to show the balance of energy that explains this preferential treatment.
        Geoff

      • For a 1 C surface warming, do you expect the ocean to also warm through its whole depth by 1 C? It doesn’t. It warms gradually from the top down, and its mean temperature change so far is much less than 1 C, but its surface temperature change is most of 1 C. The resulting expansion contributes measurably to sea-level rise, more than the melting glaciers so far, but the melting is catching up fast.

      • Geoff, Jim

        The clear message of this data, showing correlation between lagged global temperatures and obliquity:

        is that radiative changes do change climate – after a delay of 6,500 years.
        So IF Co2 starts increasing in 1950, and IF that CO2 does cause increase in insolation, then we can expect the warming from this to start in 6,500 years time, too late to have any effect on glacial inception in the next 2000 years or so.

      • O yes and it helps of the radiative peak coincides with a peak of maximal precession amplitude and 65N summer insolation.

      • For CO2 and the sun, the effect is immediate. We see it in the temperature. You can ask others why the obliquity appears delayed, but it has no application when you directly change the forcing, which obliquity only does through a roundabout sequence of events that appear to take some time to build up.

      • Jim
        Sorry you’ll need more than appeal to authority for this one.
        The mechanism of CAGW is a change to insolation due to CO2.
        The mechanism of Milankovitch forcings is change to insolation.
        They are the same.
        If one is delayed, both are delayed.
        The Climagesterium must fess up to the fact that they have made a colossal error in ignoring the ocean and imagining that climate is a matter of atmosphere only, and that radiative effects operate fantastically in real time.
        The message of obliquity is inescapable – radiative forcing influences climate with a time lag of 6000-7000 years to allow it to change ocean temperature.
        You’re trying to boil a really big kettle.

      • AGW has nothing to do with insolation. It is a direct application of infrared heat to the atmosphere and surface. This has an immediate effect for the same reason that sunrise has. No magical delay needed.

      • The Climagesterium must fess up to the fact that they have made a colossal error in ignoring the ocean and imagining that climate is a matter of atmosphere only, and that radiative effects operate fantastically in real time.
        The message of obliquity is inescapable – radiative forcing influences climate with a time lag of 6000-7000 years to allow it to change ocean temperature.
        You’re trying to boil a really big kettle.

        A powerful argument in my opinion. The oceans rule this game, despite the importance of the atmosphere.

      • Important lag effect and the difference between transient and equilibrium responses. AGW has this.

    • ferdberple,

      It is clear that low CO2 is not the cause of glaciations, since as you point CO2 is near maximal at the end of interglacials and can remain elevated for thousands of years while temperatures fall and ice starts to accumulate on continents. The cause of glaciations is falling obliquity, the only factor that is consistent over each and every glacial inception.

      And it is clear also that ~ 300 ppm CO2 cannot prevent a glaciation. Nobody knows what concentration of CO2, if any, could prevent a glaciation. Ice Ages in the past appear to have taken place at much higher CO2 levels than we currently enjoy, however some scientists believe that with >400 ppm a glaciation shouldn’t take place, while others don’t think so. Since after 38 years we still don’t know the climatic effect of doubling CO2 concentrations (climate sensitivity), I think it is premature to declare the Ice Age dead.

      If it turns out that climate sensitivity is low, we will have to work hard to put a lot more CO2 into the atmosphere to prevent a new glaciation. Perhaps we could make a new international agreement at Paris to increase CO2 emissions and help developing countries produce more.

      • If it turns out that climate sensitivity is low, we will have to work hard to put a lot more CO2 into the atmosphere to prevent a new glaciation. Perhaps we could make a new international agreement at Paris to increase CO2 emissions and help developing countries produce more.

        No. The world’s elite have all cosied up together in agreement with this CO2 warming nonsense. Sadly a future generation must be made to see the idiocy of this the hard way. The ice age will come, after progressive governments have put all fossil fuels out of reach, and nuclear technology has been forgotten. The only interesting question of group psycology is how far will the glaciers reach before the establishment realises that CO2 climate science might not have been settled. Of course they won’t. They’ll just cast around for witches to burn like they always do.

      • Javier,
        I enjoy and respect your posts and comments.

        In this case I hope you are joking.

        CAGW impacts may be exagerated but still lots from NOx, SOx, Hg and coal mines and slag ponds.

        Future clean energy technologies will be better for the environment.

        Hopefully, eventually fusion in the ice age glaciation time scale or at least advanced fission. Pumping more stuff into the atmosphere is an experiment we should avoid, even if CO2 is not a pollutant in the classic sense.

        Please keep the articles and comments coming though.
        Scott

      • Yes, I was being ironic by turning the situation around.

        I have nothing against burning gas for energy. Burning coal however leads to important pollution unless strict measures are taken to prevent it, and is less efficient. Burning oil is a waste. It is precious stuff as chemical feedstock and should be saved instead of burned. If we ever find that we need more CO2 in the atmosphere we could always burn limestone if we have plenty of energy.

      • Javier
        Thanks. I was worried. One could use ” or sarc for us literal minded.
        Scott

    • Geoff Sherrington

      Jim D,

      Sorry, but you are wrong.
      The sea rise from heating results from a different distribution of energy in the water. Molecules move further apart. The way they move is unaffected by any depth of water below; the molecules are ignorant of what is below.
      I did not suggest that the whole water column needed to reach a new temperature. You did. You did not answer the question of why liquid in a thermometer shows an anomalous change to heating, whereas the oceans so far appear to have not, as expressed by sea level, in a time of alleged record anthropogenic GHG emissions.
      Did you find that metric for the mm change in sea level per 1 deg C rise in temperature?
      Geoff.

  47. This discussion has always been won by cyclophilics.
    ==============
    there is a very sound mathematical reason for this. our mathematics does not allow us to reliably calculate the future state of any non-trivial system. the reasons have elegant names like “chaos” and the “n-body” problem, but mathematically these are equivalent problems.

    Thus we cannot for example calculate the ocean tides knowing that gravity and tidal forces from the sun and moon are the cause. Most people think we calculate the tides from first principles, but we do not. Quite simply, it does not work.

    Rather, long before we knew what caused day and night, or what caused the seasons, we learned how to calculate them. The technique is called Astrology. By recording the position of the objects in the sky, we learned than when the patterns in the sky repeat, the patterns on earth also repeat.

    And to this day that is the only reliable method we have discovered to predict the future state of complex events on earth. So for example, when the position of the sun repeats, the hour and seasons repeat. When the position of the sun and moon repeat, the ocean tides repeat.

    And as we now know, when the position of the earth in its orbit repeats, the climate repeats. The reason for this we don’t know, beyond some reasoned speculation. Any more than early humans knew what caused the hour or the season.

    But what we do know for sure is that no climate model is actually calculating future climate. Our mathematics does not know how.

    • “In 1953-1954 he made a seminal contribution to the fundamental problem of classical mechanics, identified fifty years earlier by H. Poincare in his study of the motion of planets around the sun. Neglecting all but one planet one deals with an `integrable’ problem that is well understood. However, the small effects associated with gravitational interaction between the planets introduces a profound qualitative change related to the fact that the equations are now `nonintegrable.’ In attacking this problem, Kolmogorov’s great achievement was to develop a general theory of Hamiltonian systems under small perturbations, which has several practical applications, among others in the study of magnetic fields and plasma physics. This work also spawned, together with improvements of Kolmogorov’s pupil Arnol’d and by Moser, what is now known as the study of `KAM-tori.’ Subsequent computational studies aptly confirm Kolmogorov’s insights and have opened up the enormously fruitful field of `chaos in dynamical systems,’ which is currently attracting much attention. These studies lead, for example, to better weather forecasting.” http://www.scholarpedia.org/article/Andrey_Nikolaevich_Kolmogorov

      Day and night, the seasons, the tides and the orbits of the planets have a irregularity that is almost below the threshold of observation. Certainly with the naked senses. The analogy I suppose may be Newtonian physics in an relativistic universe.

      At scales of interest for climate we have Kolmogorov’s famous studies of the Nile River. Flows there have an irregularity we characterise as persistence and regime shifts. Hydrologically we can trace this back to changes in the state of both the Pacific and Atlantic Oceans. I have hypothesised a solar trigger for state shifts in ocean and atmospheric circulation.

      So there is a mechanism on Earth that seems fairly obvious – but the system is chaos within chaos and the evolution of solar activity over the 21st century is still very uncertain. Smoothing data to identify mooted cycles helps not at all.

      • Geoff Sherrington

        RIE writes “What is more certain is that the next global climate shift is due in a 2018-2028 window.”

        Robert, there is no more certainty in this prediction than in a prediction that it will rain at your home next Christmas Eve. Worse, I suspect that you know this.
        Kolmogorov’s famous studies of the Nile River produced fascinating mathematical analyses, which are of use when applied correctly. Let’s not try to dodge “correctly” please. My comment is NOT an argument that stationarity is an unimportant concept, merely that misuse is.

        Geoff

      • “This study uses proxy climate records derived from paleoclimate data to investigate the long-term behaviour of the Pacific Decadal Oscillation (PDO) and the El Niño Southern Oscillation (ENSO). During the past 400 years, climate shifts associated with changes in the PDO are shown to have occurred with a similar frequency to those documented in the 20th Century. Importantly, phase changes in the PDO have a propensity to coincide with changes in the relative frequency of ENSO events, where the positive phase of the PDO is associated with an enhanced frequency of El Niño events, while the negative phase is shown to be more favourable for the development of La Niña events.”

        These quasi-periodical climate shifts of 20 to 30 year duration have been happening for as long as there are proxy records. It is explained in the link.

        “Perhaps the most significant contribution of the intensifying climatic research is the accumulation of evidence that climate has never been static. Rather, it has been ever changing at all time scales. The changing character of climate, verified for the past or predicted for the future, has been sometimes described by the term nonstationarity. However, revisiting the notions of stationarity and nonstationarity, which are defined within stochastics, we may understand that the terms are often abused. Literally, claims of nonstationarity cannot stand unless the evolution in time of the statistical characteristics of the process is known in deterministic terms not only for the past, but also for the future in particular. This however can hardly be the case, because, as is known, deterministic predictions are difficult, especially of the future.

        Change is not synonymous to nonstationarity, since even an ideal stationary white noise process involves change, which however becomes less and less distinct as the time scale of viewing the process (e.g., time scale of averaging) increases. However, the climatic and all geophysical processes demonstrate more prominent change at large scales in comparison to white noise or even to typical stochastic models such as Markovian. This does not reflect nonstationarity. Rather it warns us to change our perception of natural processes as resembling these simple idealized mathematical processes and to move towards a new type of stochastic dynamics. The “new” description does not depart from the 60- to 70-year old pioneering works of Hurst on natural processes and of Kolmogorov on turbulence. Essentially, Hurst’s discovery in 1950 of the behaviour named after him and the model that had been proposed by Kolmogorov 10 years earlier recognize the multi-scale fluctuation of natural processes and describe it in stationary terms.” http://www.cwi.colostate.edu/NonstationarityWorkshop/SpeakerInfo/Koutsoyiannis_Abstract.pdf

        I am pretty sure Geoff pulls it out of his arse.

      • RIE
        If you are enlightened in the chaotic dynamics of Kolmogorov and of Hamiltonians, then when will the penny drop that 20th century warming might be an internal chaotic fluctuation?

      • Robert

        I am pretty sure Geoff pulls it out of his arse.

        You are an infantile twat.

      • “If as suggested here, a dynamically driven climate shift has occurred, the duration of similar shifts during the 20th century suggests the new global mean temperature trend may persist for several decades. Of course, it is purely speculative to presume that the global mean temperature will remain near current levels for such an extended period of time. Moreover, we caution that the shifts described here are presumably superimposed upon a long term warming trend due to anthropogenic forcing. However, the nature of these past shifts in climate state suggests the possibility of near constant temperature lasting a decade or more into the future must at least be entertained.” If as suggested here, a dynamically driven climate shift has occurred, the duration of similar shifts during the 20th century suggests the new global mean temperature trend may persist for several decades. Of course, it is purely speculative to presume that the global mean temperature will remain near current levels for such an extended period of time. Moreover, we caution that the shifts described here are presumably superimposed upon a long term warming trend due to anthropogenic forcing. However, the nature of these past shifts in climate state suggests the possibility of near constant temperature lasting a decade or more into the future must at least be entertained.” http://onlinelibrary.wiley.com/doi/10.1029/2008GL037022/full

        The 20 to 30 year period since the last shift – based on a 1000 years of data – is up in a window of 2018 to 2028. This is not at all like predicting rain at Christmas as Geoff suggests.

        “Kolmogorov’s famous studies of the Nile River produced fascinating mathematical analyses, which are of use when applied correctly.” GS

        I really have to admit to a brain fade. It was in fact Hurst who studied Nile River flows with a methodology that has become known as Hurst-Kolmogorov stochastic dynamics. Geoff obviously had a brain fade as well.

        “In comparison to our toy model, a natural system, such as the atmosphere, a river basin, etc.: (a) is much more complex; (b) has time-varying inputs and outputs; (c) has spatial extent, variability and dependence (in addition to temporal); (d) has greater dimensionality (virtually infinite); (e) has dynamics that to a large extent is unknown and difficult or impossible to express deterministically; and (f) has parameters
        that are unknown. Hence uncertainty and unpredictability are naturally even more pronounced in a natural system. The role of stochastics is then even more crucial: (a) to infer dynamics (laws) from past data; (b) to formulate the system equations; (c) to estimate the involved parameters; and (d) to test any hypothesis about the dynamics. Data offer the only
        solid ground for all these tasks, and failure to rely upon, and test against, evidence from data renders inferences about hypothesized dynamics worthless.” http://www.hydrol-earth-syst-sci.net/14/585/2010/hess-14-585-2010.pdf

        Koutsoyiannis always has an interesting perspective. People like ptolemy2 rattle off terms like Kolmogorov chaotic dynamics and Hamiltonians – as if there is a mathematical representation of the high dimensional chaos of climate. There isn’t – nor is it predictable. Kolmogorov solved nonintegrable Hamiltonians for turbulence and planetary motions. A nonintegrable Hamiltonian is one that does not smoothly evolve. It is the difference between chaos and regularity. There is no equivalent function for climate. But it suggests – there’s that abductive inference word again –
        that the data should be analysed for Hurst-Kolmogorov stochastic dynamics. The link above is an intro.

      • “Interdecadal 20th century temperature deviations, such as the accelerated observed 1910–1940 warming that has been attributed to an unverifiable increase in solar irradiance (4, 7, 19, 20), appear to instead be due to natural variability. The same is true for the observed mid-40s to mid-70s cooling, previously attributed to enhanced sulfate aerosol activity (4, 6, 7, 12). Finally, a fraction of the post-1970s warming also appears to be attributable to natural variability.” http://www.pnas.org/content/106/38/16120.full

        YES I KNOW I HAVE QUOTED THIS BEFORE – PEOPLE SEEM A LITTLE HARD OF HEARING.

      • Robert
        Nice paper (Swanson et al 2009), thanks.
        Tsonis’ group have looked at chaos-nonlinearity in climate quite a lot, I recall. Can one describe the climate system as a (weakly) periodically forced nonlinear oscillator, in terms of the interaction of its internal nonlinear dynamics with external periodic forcing?

    • While the idea that future climate is unpredictable is correct in the main, that is the case because of the general lack of truly periodic variations (over time-spans of human proportions).

      But, entirely contrary to the notion that

      we cannot for example calculate the ocean tides knowing that gravity and tidal forces from the sun and moon are the cause

      the astronomical tidal forces are no less predictable from first principles than sunrise times or equinoxes. Only the position of the Earth in its orbit and geographic location need be specified along with lunar phase. Tidal tables mathematically generated decades in advance using but a score of strictly periodic tidal constituents (so-called Doodson numbers) usually provide reliable determinations of tidal stand at coastal locations with reasonably regular bathymetry offshore.

      The tides provide an unfit example of a good point about climatic variability.

  48. Javier,

    Can you please give a link to the source for Figure 49. I haven’t found it on Knownuthing Game over https://www.rankia.com/blog/game-over/3113785-ciclos-glaciales

  49. There are three methods of heat transfer. They are conduction, convection, and radiant heat. Heat transfer to or from the earth can only be done by radiant. All material contains heat and is radiating it to cooler surfaces or absorbing it from warmer surfaces. The difference is the heat gain or loss of the material.
    The earth gains heat radiated from the sun and loses heat it radiates to outer space, called black sky radiation. Outer space is considered absolute zero.
    The amount of radiant heat hitting the earth from the sun daily is relatively constant. The radiant heat lost daily by the earth thru black sky radiation is constant since absolute zero is constant. The amount of heat gained by the earth’s surface depends on the surface area of the earth covered by water relative to that covered by land. Land area absorbs a larger percent of the radiant heat relative to the water area since the surface of the water reflects a percentage of the radiant heat back to outer space. The daily access heat, or loss of heat, is transferred to the oceans thru conduction and convection where it works its way to the poles and it freezes water adding to the polar ice caps or melts the polar ice caps thus keeping the temperature of the oceans, thus the earth, relatively constant. As the polar ice caps grow or melt, the surface area of the earth covered by land relative to that covered by water changes. This is the definition of global warming.
    That radiant heat absorbed by oceans and land masses is transferred to the atmosphere thru conduction and convection. When it is winter in one hemisphere it is summer in the other and the same with spring and fall. I would think the average temperature of the lower 5,000 feet of the atmosphere changes about 10’F to20’F each day. This probably takes more heat than man has added to the earth in the last 50 years. That heat man adds to the atmosphere each day is radiated to the black sky and the infinitesimal amount left helps melt the ice during global warming, should be called Global Defrosting, . The scientists have taken core samples of the polar ice caps and know how close we are to the ice left at the beginning of the last ice age. That is how close we are to the end of global warming or we have already begun global cooling, should be called global ice making. According to the Antarctic ice core we began the new ice age about 11,000 years ago.
    Absolute Zero is -459.68’F and the surface temperature of the sun is between 7,300’F and 10,000’F. If we could go back in time 12,000 years, the end of the last ice age, we would probable see that the average daily temperature of the earth was in the mid 60’F as it is today. You must understand the amount of heat gained every 24 hours is almost equal to that lost during the same 24 hours. Angle of the earth’s axis is 23.5’.
    The above in simple English.
    The average surface temperature of the earth is 63.5’f. The heat loss to black sky radiation every 24 hours is constant. The average radiant heat striking the surface of the earth is relatively constant. Because the sun is an active star the average temperature will change over centuries.
    The ocean is the flywheel and supplies the heat when the earth loses more heat than it keeps. This cycle should take about 140 thousand years. 70 thousand years making the ice. 70 thousand melting it. The Almighty designed the perfect system. I will try to stay around and watch it thru.

    • There are three methods of heat transfer. They are conduction, convection, and radiant heat.

      Aren’t you forgetting evaporation, which is the principal mechanism of heat transfer from oceans to atmosphere?

  50. Javier,

    Can you please answer the pretty simple question:

    can you please provide a link to the source for Figure 49. I haven’t found it on Knownuthing Game over https://www.rankia.com/blog/game-over/3113785-ciclos-glaciales

    Surely that is not too hard for you to do. The fact you keep dodging simple questions just asking for a source for one of your figures is not an indication of intellectual honesty. https://judithcurry.com/2013/04/20/10-signs-of-intellectual-honesty/ You did the same on previous threads where you would not provide a source to this figure, which I subsequently found had been manipulated (by you?) and is highly misleading:

  51. My theory in short, is it is a weak solar/increase albedo/lower sea surface temperature play due to very weak prolonged solar conditions and more importantly the secondary effects that could rise from these very weak solar conditions that could bring the climate to thresholds compounded by a weakening earth magnetic field.

    All natural variability on earth is due to outside influences mainly the sun and the geo magnetic field in my opinion.
    Another theory on the cause of Ice Ages is a change in total atmospheric pressure much more on this can be found on talkblokes talkshop website.

    Came out a few days ago.

  52. Javier

    Can you give the reference(s) for the 6500 year lag or delay between obliquity forcing and interglacial inception and termination, shown convincingly in this figure (fig 35 in nature unbound):

    I’m not doubting the lag, it is acknowledged in the literature, for instance by even Ruddiman (who deviously refers to it as a lag between obliquity and CO2, not temperature of which CO2 is simply a proxy):

    Ruddiman WF. The anthropogenic greenhouse era began thousands of years ago. Climatic change. 2003 Dec 1;61(3):261-93.

    • Sorry Ptolemy2,

      I just took EPICA Dome C temperature data and Laskar et al., 2004 astronomical obliquity data and found a best fit by sifting the temperatures. I supposed Ruddiman calculated it in a similar way for CO2 (or temperatures). I was unaware of his calculation, but anybody doing it should come with a similar answer. I can’t provide a citation since I don’t remember reading it, but I wouldn’t be surprised if it has been reported multiple times.

      Anyway something so obvious that nearly anybody can check by themselves with a computer in a moment doesn’t really require a citation. That’s probably why Ruddiman didn’t bother putting it in the methods or finding a citation.

  53. Javier points of disagreement

    Co2 has no influence on the climate

    Galactic cosmic rays do influence the climate by promoting ore cloud coverage.

    There is a volcanic /solar link.

    Chances are solar activity will be at Dalton Levels gong forward.

    Global temperatures are now starting their decline in response to very low solar conditions.

    • Co2 has huge influence on the climate.
      CO2 makes green stuff grow and more green stuff makes for a better climate. Less CO2 makes green stuff not grow and less green stuff makes for death to life as we know it.
      Earth takes care of temperature in a different way. In warm times it snows more and makes earth colder. In cold times it snows less and lets earth get warmer. This is a natural cycle and we do not control it. We may influence it, but we cannot push it out of bounds. Earth’s cooling system is well designed by a higher power or by really good luck.

  54. JAVIER THIS GUS KNOWLEDGE IS GREATER THEN MINE AND HE HAS IT SPOT ON. THIS GUY KNOWS HIS STUFF TO THE HILT. WILLIAM ASTLEY WOULD BE A GREAT PERSON TO HAVE ON THIS SITE AND FEATURE HIS THOUGHTS.

    William Astley

    June 8, 2017 at 10:22 am

    Leif,
    Why would you expect any increase in the solar large scale magnetic field?

    I predicted that the solar large scale polar field will drop to levels not believed possible, for the following reasons:

    The solar large scale magnetic field origin’s is residue magnet flux from sunspots.

    It is a fact that sunspots have been gradually disappearing (this is an observation that requires an explanation not a theory) as the magnetic strength of the magnetic flux tube that rise up to the surface of the sun to form a sunspot group decrease in strength. There is a tipping point. When the magnetic flux tube strength of the flux tube falls below a critical value the flux tube are torn apart.

    As the process continues and magnetic flux strength of the sunspot group declines, the lifetime of a sunspot group (of the few sunspot groups that do form) has decreased to where we are now at the point that a sunspot group’s lifetime is for a number of cases only a few days. In past cycles the lifetime of sunspot group has a couple of weeks and the odd sunspot group lifetime was sufficient that it re-immerged.

    P.S.
    As I stated 6 months ago. The super large solar coronal holes are disappearing. The solar wind bursts from coronal holes is one of the reasons why the planet has not cooled.

    Coronal holes produce a recurring solar wind burst which in turn (for low latitude coronal holes) creates a space charge differential in the earth’s ionosphere which in turn causes an electric current to flow from high latitude regions to the earth’s equator.

    The global electric current causes changes in cloud properties and precipitation which in turn causes warming in both locations. This the explanation for the linked changes temperature in geographically separate regions of the earth.

    The solar wind bursts cause a warming of about 7 watts/m^2 as compared to the incorrect estimated warming for a doubling of atmospheric CO2 of 3.7 watts/m^2.

    http://sait.oat.ts.astro.it/MmSAI/76/PDF/969.pdf


    Once again about global warming and solar activity
    We show that the index commonly used for quantifying long-term changes in solar activity, the sunspot number, accounts for only one part of solar activity and using this index leads to the underestimation of the role of solar activity in the global warming in the recent decades. A more suitable index is the geomagnetic activity which reflects all solar activity, and it is highly correlated to global temperature variations in the whole period for which we have data.

    The real terrestrial impact of the different solar drivers depends not only on the average geo-effectiveness of a single event but also on the number of events.

    Figure 5 presents the yearly number of CHs, CMEs and MCs in the period 1992-2002. On the descending phase of the sunspot cycle, the greatest part of high speed solar wind streams a affecting the Earth comes from coronal holes (Figure 5), in this period their speed is higher than the speed of the solar wind originating from other regions, and their geoeffectiveness is the highest.

    Therefore, when speaking about the influence of solar activity on the Earth, we cannot neglect the contribution of the solar wind originating from coronal holes. However, these open magnetic field regions are not connected in any way to sunspots, so their contribution is totally neglected when we use the sunspot number as a measure of solar activity.

    See section 5a) Modulation of the global electrical circuit in this review paper, by solar wind bursts and the process electroscavenging.

    http://gacc.nifc.gov/sacc/predictive/SOLAR_WEATHER-CLIMATE_STUDIES/GEC-Solar%20Effects%20on%20Global%20Electric%20Circuit%20on%20clouds%20and%20climate%20Tinsley%202007.pdf


    The role of the global electric circuit in solar and internal forcing of clouds and climate

    The solar wind affects the galactic cosmic ray flux, the precipitation of relativistic electrons, and the ionospheric potential distribution in the polar cap, and each of these modulates the ionosphere-earth current density. On the basis of the current density-cloud hypothesis the variations in the current density change the charge status of aerosols that affect the ice production rate and hence the cloud microphysics and climate [e.g., Tinsley and Dean, 1991; Tinsley, 2000].

    The underlying mechanism is that charged aerosols are more effective than neutral aerosols as ice nuclei (i.e., electrofreezing) and that the enhanced collections of charged evaporation nuclei by supercooled droplets enhance the production of ice by contact ice nucleation (i.e., electroscavenging).

    Both electrofreezing and electroscavenging involve an increase in ice production with increasing current density [e.g, Tinsley and Dean, 1991; Tinsley, 2000]. The current density-cloud hypothesis appears to explain solar cycle effects on winter storm dynamics as well as the day to-day changes of Wilcox and Roberts Effects [e.g., Tinsley, 2000]. Kniveton and Todd [2001] found evidence of a statistically strong relationship between cosmic ray flux, precipitation and precipitation efficiency over ocean surfaces at midlatitudes to high latitudes, and they pointed out that their results are broadly consistent with the current density-cloud hypothesis.

    There is now obvious evidence of high latitude cooling which is not surprising as the planet cyclically warms and cool.

  55. Pingback: climate change | There is no box

  56. Javier, you love to do and have access to information. Can you post a graph of the different RCP’s and observed temperatures, perhaps with CO2 generation forecast with observed. How close are they to reality.

  57. Javier this video is great need to hear it .

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