3 degrees C?

by Judith Curry

Is 3 C warming over the 21st century now the ‘best estimate’?  A reframing of how we think about climate change over the 21st century, and my arguments for 1 C.

There has been much discussion over on twitter of the new article by David Wallace-Wells:  We’re Getting a Clearer Picture of the Climate Future — and It’s n Not as Bad as it Once Looked.  ‘This article is interesting for several reasons, especially since Wallace-Wells has been ‘alarmist in chief.’

Simply put, it is now becoming more widely accepted that RCP8.5 concentration/emissions scenario is highly implausible.  See my previous post:

A new article by Zeke Hausfather and Justin Ritchie at the Breakthrough Institute is entitled ‘A 3C World is Now ‘Business as Usual‘.  Punchline:

“We find that IEA numbers imply that the most likely outcome of current policies is between 2.9-3.4C warming — which is reduced to around 2.7-3C warming if countries meet their current Paris Agreement commitments.

Uncertainties surround this projection, of course. For one, there are uncertainties in the sensitivity of the climate to rising atmospheric greenhouse gas concentrations that mean emissions expected to produce warming of around 3C could result in warming as little as 1.9C or as much as 4.4C.”

They calculate the amount of warming based on TCRE:

“The amount of warming the world is projected to experience can be pretty closely approximated solely based on cumulative CO2 emissions. This relationship between temperatures and cumulative emissions is referred to as the transient climate response to cumulative carbon emissions, or TCRE. Using the TCRE values developed in the IPCC Special Report on 1.5C (SR15), we can calculate the amount of warming expected over the remainder of the century in our extended IEA scenarios, as well as the uncertainty introduced by the wide range of possible climate sensitivity values.”

“In the figure below we show the amount of warming between the last decade of the 20th century and the temperature of the late 1800s (which is somewhat representative of preindustrial temperatures) for the four RCP scenarios used in the IPCC AR5 and the extended IEA STPS and CPS cases — assuming flat emissions in each after 2040. The width of each bar reflects the 90th percentile range of warming given the uncertainty in climate sensitivity, while the central point represents the average of all the climate models running that scenario.”

This is a nice analysis by Hausfather and Ritchie.  Some questions, suggestions and criticisms are outlined below:

Baseline

The 3 C estimates in the paper by Hausfather and Ritchie are based on a baseline period  1880-1900.    The canonical rationale is for ‘preindustrial’, which would be mid 18th century, as the Northern Hemisphere was coming out of the Little Ice Age (hardly a climate ‘optimum’).  But then, ‘good’ data is available only since the late 19th century.

The rationale for a baseline for manmade global warming in either the 18th or 19th century is that this is when manmade global warming began. There are multiple takes on this, and how much of the early warming was caused by CO2 emissions.  Here are some previous blog posts:

The public looks at the 3 C number and thinks it is 3 C more warming from NOW, not since the late 19th century.  Warming from NOW is what people care about.

In terms of projecting the amount of warming in 2100, what is the point in going back to 1900, and including all of the 20th century warming as ‘manmade’?  It is far simpler to bypass the attribution issues of 20th century warming, and start with an early 21st century baseline period — I suggest 2000-2014, between the two large El Nino events.

In terms of policy, what matters is how much warming we can expect over the 21st century.  Yes, the blame game in terms of 20th century warming is useful in terms of motivating people to act on reducing fossil fuel emissions.  But at this point, what matters for decision making is how much warming we can expect over the remaining 80 years of the 21st century.

While we complain about the 21st century ‘weather’ and now call them ‘climate disasters’, few of them have plausible arguments for being associated in any way with manmade climate change.  Overall the weather in the early 21st century is relatively benign by the standards of the Little Ice Age or even the early 20th century. The slow creep of sea level rise started circa 1860, well before there was significant manmade global warming.

If you start from an early 21st century baseline, you can subtract 1C from the 3C.  Simple . . .  now we are down to 2C.

TCRE

Nic Lewis wrote a previous post on TCRE: Climate sensitivity to cumulative carbon emissions.   Excerpt:

“There are two principal metrics for sensitivity to cumulative carbon emissions. The best known is the transient response to carbon emissions (TCRE). This measures the change in global mean surface temperature (GMST) at the end of a period, typically of the order of a century long, during which CO2 is emitted smoothly. TCRE is stated per 1000 GtC (≡ 1 TtC) emissions, and usually assumes a total of 1000 GtC is emitted. Note that 1000 GtC is the carbon content of 3667 GtCO2.

In CMIP5 earth system models (ESMs), which couple carbon cycle models with atmosphere-ocean global climate models, TCRE ranges from 0.8°C to 2.4°C, with a mean of 1.6°C. The assessment in AR5, which largely mirrors the CMIP5 ESM range, was that the TCRE is likely between 0.8°C to 2.5°C, for cumulative CO2 emissions less than about 2000 GtC, until the time at which temperatures peak. ”

Nic calculated the observationally-based values of TCRE to be 1.05°C.

“The observationally-based TCRE estimate of 1.05°C, although within the AR5 range and the almost identical CMIP5 ESMs model range, is little more than half the level reflected in the central RCP scenario projections in the AR5 SPM.10 chart. Assuming that the 1.05°C estimate is realistic going forward, the IPCC’s chart overstates expected 21st century warming by a factor of approaching two, for all scenarios.”

Yes, there is uncertainty in the observationally-assessed value of TCRE.  Similar to the LC18 results, the observationally-based values of climate sensitivity are slightly more than half of the model-derived values.

Lets do math.  With a different baseline, we are now down to 2C.  Multiply 2C by 0.6 (reduced values of TCRE) to yield a warming of 1.2C.

Natural variability

The IPCC’s 21st century climate change predictions do not include natural variability, they are focused only on manmade climate change.  Excerpts from the IPCC AR5:

“With regard to solar forcing, the 1985–2005 solar cycle is repeated. Neither projections of future deviations from this solar cycle, nor future volcanic radiative forcing and their uncertainties are considered.”

“Any climate projection is subject to sampling uncertainties that arise because of internal variability. [P]rediction of the amplitude or phase of some mode of variability that may be important on long time scales is not addressed.”

So . . . does natural climate variability matter for the 21st century climate?  Of course it does.  The common argument is that natural variability is of small amplitude and we don’t know whether it will contribute to warming or cooling, since we can’t predict it.

Well, is anyone predicting another solar maximum in the 21st century, similar to what we saw in the mid/late 20th century?  No . . . rather, there are some predictions for solar cooling in the mid 21st century.  Whether there will be a major solar minima in the 21st century is highly uncertain, but the more telling point is that no one is predicting a new maximum.  In any event, endlessly repeating the 1985-2005 solar cycle doesn’t seem to be a particularly good bet.

Re volcanoes, the 20th century was quite benign in terms of volcanic eruptions.  There were much worse volcanic eruptions in the 18th and 19th centuries.  Is there any particular reason to expect the 21st century volcanic eruptions to be as benign as the 20th century.  You have to go back to the period 1340-1440 to find another century long period as benign as the 20th century volcanoes.

Now for the multi-decadal and longer ocean oscillations.  For the past 25 years, we have been in a regime dominated by  the warm  phases of  AMO.  Is anyone predicting that the warm phase will persist through the 21st century?  No . . . transition to the cool phase are expected before mid century.

While we can’t predict future solar, volcanic and long term ocean oscillation activity,  we can expect multidecadal periods in the 21st century where the external forcing tends towards cooling and also the ocean oscillations support cooling, reduced Greenland ice melt, etc.

Net cooling from natural sources of 0.2C or more is not at all implausible over the 21st century; it is difficult to argue for additional warming from natural sources over the 21st century.

1.2 C minus 0.2 C = 1.0 C

Dangerous?

1.0 C warming for the remainder of the 21st century seems pretty benign.  But if you add the ~1.0 C warming since 1890, then we are at 2 C – ‘dangerous’

2C, and then 1.5C, are the touted values of ‘dangerous’ climate change.  Some context on ‘dangerous’, and some different perspectives in these previous blog posts:

Simply put, in terms of  ‘dangerous’ we are looking at extreme weather events, sea level rise and species extinction.  I’ve written numerous posts on all of the above, won’t rehash here, other than to point you to the recent  IPCC Special Report on Oceans, Cryosphere and Climate, since sea level rise is one issue that is very directly and monotonically  linked to warming.  Their main conclusion regarding sea level rise:

“Projections of global mean SLR under RCP2.6 result in 0.42 m (0.28–0.57 m; likely range) in 2100. Projections of global mean SLR under RCP4.5 results in0.55 m (0.39–0.71 m, likely range) in 2100. Projections of global mean SLR under RCP8.5 results in 0.97 m (0.55–1.40 m) in 2100.”

If you take out the highly implausible RCP8.5, then we are left with 1-2 feet by 2100, compared to ~7 inch rise in the 20th century.  And these values are biased high from climate model simulations that don’t sample the full ‘likely’ range of ECS from the IPCC AR5 – no climate model values between 1.5 and 2.3 C.

The issue of 2 C as ‘dangerous’ is tied to concerns about tipping points, and massive melt of ice sheets that were observed in previous interglacials at comparable temperature.  My main response to that concern is a request to paleoclimatologists to sort out what was going in the mid-Holocene ‘climate optimum’,  when there is at least anecdotal evidence of much warmer temperatures and higher sea level. (Note re the last 2000 years; I’ve yet see convincing evidence that MBH-style shenanigans have disappeared from PAGES2K, etc.)

Conclusions

1.2 C of additional manmade warming over the remainder of the 21st century isn’t ‘dangerous.’  Yes, there is substantial uncertainty in how the climate of the 21st century will actually play out, and we will undoubtedly be surprised.

But reframing the ‘warming’ with an early 21st century baseline, rejecting RCP8.5  and using more credible values of TCRE goes a long way towards putting manmade global warming into perspective over the course of the 21st century.

261 responses to “3 degrees C?

  1. Curious George

    Many clowns predict catastrophic anything (temperature, rains, droughts, hurricanes, diseases, famines) for year 2100, most likely because they’ll be safely retired by then. Can they provide us with a reliable forecast (not a projection; a forecast!) for year 2024?

    Merry Christmas and a happy New Year, everybody.

    • I can. I forecast that winter will be colder than summer in 2024. Grin. Happy holidays to all!

    • “…..they’ll be safely retired by then.”

      I thought about that when I read this article.

      “Consider two roads. One leads to 2 feet of global-average sea-level rise over the course of this century, and swamps land currently home to about 100 million people. The other leads to 6 feet of rise, swamping the homes of more than 150 million. Our new study, published today in the journal Earth’s Future, finds that – at least from measurements of global sea level and continental-scale Antarctic ice-sheet changes – scientists won’t be able to tell which road the planet is on until the 2060s.”

      Another 40 years will give them enough time to get out of Dodge if the worst doesn’t come to pass. Based on actual observational data from Tidal Gauges, I will put my money on 1 foot by 2100.

      http://www.impactlab.org/news-insights/kopp-ice-sea-level-rise-projections/

  2. “While we can’t predict future solar”

    My group has been predicting solar for the last decade and if our 4kyr and sunspot history since 1748 hindcasts and the limited results since our 2013 forecast are anything to go by, our method looks useful.

    https://tallbloke.files.wordpress.com/2019/01/salvador-sunspot-model-updated.png

    Paper: http://www.pattern-recogn-phys.net/1/117/2013/prp-1-117-2013.pdf

    • Without you looking at my findings on the role of Uranus in Spring 2013 that paper would not exist, and it’s a dogs dinner. You can’t just feed a quarter of a Uranus orbital period in the JEV mix, the solar cycle timings are governed by quadrupole alignments and not average periods. The JEV series falls of sync with Uranus after 7-10 solar cycles and then resolves to Neptune instead during each centennial solar minimum until the JEV series can physically regain sync with Uranus again. This progression entirely accounts for all solar cycle length variability. The standard cycle length is nominally 6.5 EV synodic periods at 10.39 years, and with longer cycles leading into and out of each centennial solar minimum. In the middle of longer centennial minima even shorter cycles occur because the JEV series return faster to Neptune than to Uranus, as through the 1680-90’s. If you carefully study the phase relationships between VE syzygies and UJ syzygies, the occurrence and frequency of centennial minima is self explanatory. And in the long term it all resolves to JEVU synodic periods, at 1726.62 years, with grand solar minima series occurring at the half cycle on average every 863 years. This is due to visible displacement of the alignments which physically produces a series of longer centennial minima.

      • Hi Ulric. From a comment I made in 2012 at the talkshop:

        “It’s also worth noting that the other main harmonic of Jupiter and Uranus gives the average of one of the two common solar cycle length ranges:
        84.01*11.86/(84.01+11.86)=10.39 years (Which also coincides with the JEV syzygy cycle). The other being the Jupiter orbital period of 11.86 years
        This observation is thanks to the late Timo Niroma”
        https://tallbloke.files.wordpress.com/2010/07/niroma-ss-lengths.jpg
        As Rick Salvador indicates in his 2013 paper, it was talkshop contributor ‘Sparks’ who graphically represented the Uranus 1/4 orbital period at his website http://thetempestspark.wordpress.com/ (Now defunct).
        https://tallbloke.wordpress.com/2012/11/25/ian-wilson-tidal-torque-model-of-solar-planetary-interaction/comment-page-1/#comment-36509

      • In the paper that you linked above, Salvador acknowledges “Roger Tattersall for pointing out the Uranus one-quarter frequency”.
        That blog link doesn’t contain your quote, but I note Ian Wilson (Ninderthana) replying to a comment of mine which is deleted, and Sparks makes no mention of Uranus there. Your quote is from this post:
        https://tallbloke.wordpress.com/2012/11/19/gravity-solar-z-axis-a-casual-look/#comment-35838
        The Jupiter-Uranus nodal cycle of 10.39 years is immaterial, it cannot maintain a long term parity with their syzygies and quadratures. It’s not the right reference. The effective geometric Jupiter-Uranus value for the shorter solar cycles is 0.75 of a J-U synodic cycle, as each cycle maximum alternates between approximate J-U syzygies and J-U quadratures. Until they drift out of sync with E-V and a centennial minimum occurs.

      • Another problem with Salvador’s model is with the timing of each minimum and maximum, because it fails to reproduce the geometry of the solar cycles. Which for the shorter cycles is nominally a 0.25 J-U synodic period on the rising phase, and a 0.5 J-U synodic period on the declining phase.
        p.s. Ian’s comment was in fact reproducing your reply from the link, my error.

      • I should have written ‘axial cycle’ not ‘nodal’.

      • I think what probably happened was that my findings gave support for Uranus being involved, but you decided to opt for Uranus quarter orbital magnetic phase changes, so I should fairly withdraw the plagiarism complaint in my other comment. But the main issue is that the model cannot work. It cannot capture the change of cycle length into and out of centennial minima. The interference pattern which the ‘new extended minimum’ prediction is based on is thoroughly specious. And in figure 8, it badly fails to keep track of pre 1750 solar cycles, 12 solar cycles ahead of 1615 should be 1750 and not 1715.
        https://snipboard.io/qXKCgo.jpg

      • From the Salvador paper:

        “Individual sunspot cycles have varying cycle lengths and this is an impediment to obtaining a continuous mathematical model for correlation. The monthly sunspot data imply that frequencies and/or phasing of the basic cycles are slowly changing over time.It should be noted that the 178.8 frequency is also the time of rotation of the Sun around the barycenter. The perturbations described by the VEJ and Jovian frequencies are in the Sun, and therefore it is plausible that solar acceleration reasons could cause modulations to these frequencies (see Cionco and Campagnucci, 2012). This provided the idea that perhaps the Jovian 19.858 and 21.005 and the VEJ 22.14 frequencies and phases are changing over time to the barycenter rotation of 178.8. During this work it was also found that the 19.528 VEJ frequency is changing to the slower 1253 frequency. Likewise there is a possible explanation for this in the time it takes for the orbital realignment of Venus, the Earth and Jupiter to re-turn to the same position against the stars. See Wilson (2013Hallstatt). These frequency- and phase-changing capabilities are built into the model and for the most part solve the cycle length problem for correlation.”

        The main variance in the VEJ series alone, is because the orbits are non-circular which varies the synodic period length, and because slow slips in the synodic series means a shorter step occurs occasionally for them to maintain their synodic parity. There is no 19.528 year JEV frequency, and 165.5 years is not a JEV synodic value. Neither 19.858 or 178.8 figure in the ordering of solar cycles and centennial minima.
        The gross variability of solar length, and the reason for solar cycles between centennial minima tending to 10.4 years length instead of the 11.07 yr JEV synodic period, is that the EV inferior conjunctions resolve to Uranus at each cycle maximum. While in centennial minimum sunspot cycle maxima in 1675, 1685, 1693, 1805, 1885, and 1893, the JEV syzygies and quadratures resolve to Neptune at sunspot maximum. The longest cycles are where the JEV series slips out of sync with Uranus enough to fail to perform a quadrupole configuration, and JEV then hunts for the next available quadrupole configuration with Neptune as a surrogate; a centennial minimum. Everything is timed by the best quadrupole alignments, beat periods and frequency modulations have nothing to do with absolute solar cycle length.

      • Error, 1884 and 1894.

    • I think simple reversion to the mean suggests lower solar activity, but predicting solar activity more than a cycle out is no better than stock charting.

  3. Pingback: 3 degrees C? — Climate Etc. – Climate- Science.press

  4. … For the past 25 years, we have been in a regime dominated by both the warm phases of AMO and PDO. Is anyone predicting that these warm phases will persist through the 21st century? No . . . transitions to the cool phases are expected before mid century. …

    In the last 25 years the PDO completed a negative phase, which included the mighty DaPaws in warming:

    https://i.imgur.com/7IFT1JH.png

    The AMO went positive in 2000, and has a slight upward trend over the last 25 years. The downward trend once it goes negative? Oh the slight horrors!

    https://i.imgur.com/mYtDAWL.png

    In the last 25 years the surface as warmed at .2 ℃ per decade.

    https://i.imgur.com/fLRXYyJ.png

  5. It would be much better to work with how much warming is beneficial, rather than worrying about how much is ‘dangerous’. From all the evidence and argument that I have seen, a further 2C of warming would be very beneficial (more food growth, less winter deaths, etc), and it is not at all clear that another 1C or 2C would be harmful. You have to go a lot higher than that, I think, to get to anything dangerous.

  6. “For the past 25 years, we have been in a regime dominated by both the warm phases of AMO and PDO.”

    ??

    https://www.carbonbrief.org/wp-content/uploads/2016/06/NOAA-PDO-Index.png

  7. why are we so concerned about a 1 to 3degree C warming from pre industrial-just about the coldest period in the Holocene?

    Surely we would have much more to worry about if we hadn’t warmed up substantially from that often bitterly cold period?

    tonyb

    • Curious George

      From a layman’s perspective, I’ll start to take year-2100 projections as worth consideration when we get a reliable 100-hour weather forecast, let’s say for London. Until then, so-called “scientists” are living in a phantasy world.

      • Curious George commented:
        From a layman’s perspective, I’ll start to take year-2100 projections as worth consideration when we get a reliable 100-hour weather forecast

        Another one who doesn’t understand the difference between climate and weather. They simply refuse to learn.

      • “The global coupled atmosphere-ocean-land-cryosphere system exhibits a wide range of physical and dynamical phenomena with associated physical, biological, and chemical feedbacks that collectively result in a continuum of temporal and spatial variability. The traditional boundaries between weather and climate are, therefore, somewhat artificial. The large-scale climate, for instance, determines the environment for microscale (1 km or less) and mesoscale (from several kilometers to several hundred kilometers) processes that govern weather and local
        climate, and these small-scale processes likely have significant impacts on the evolution of the large-scale circulation (Fig. 1; derived from Meehl et al. 2001). The accurate representation of this continuum of variability in numerical models is, consequently, a challenging but essential goal. Fundamental barriers to advancing weather and climate prediction on time
        scales from days to years, as well as longstanding systematic errors in weather and climate models, are partly attributable to our limited understanding of and capability for simulating the complex, multiscale
        interactions intrinsic to atmospheric, oceanic, and cryospheric fluid motion.” https://journals.ametsoc.org/doi/pdf/10.1175/2009BAMS2752.1

        The Appellism is something echoed over decades – but is hardly a profound insight into climate or models.

      • Curious George

        I simply believe that weather and climate have the same underlying physics. How can we understand climate without understanding weather?

  8. The irony is that CO2 has no significant effect on climate.
    Simple calculations using data from Hitran show water vapor is 37+ times more effective than CO2 at ground level warming. Added cooling by increased CO2 well above the tropopause counters and perhaps exceeds the tiny added warming from more CO2 at ground level.
    Measured water vapor trend has been increasing faster than possible from feedback. https://watervaporandwarming.blogspot.com

    • Dan Pangburn wrote:
      The irony is that CO2 has no significant effect on climate.

      Does CO2 absorb infrared radiation?

      Simple calculations using data from Hitran show water vapor is 37+ times more effective than CO2 at ground level warming.

      What calculations?

      When are you going to publish your findings in the peer reviewed journal literature and astonish the world? What are you waiting for?

      Don’t you want to win a Nobel Prize?

      • DA, CO2 also emits LWIR. Increased CO2 emission above the tropopause counters the added absorption at ground level.

        Apparently you are too stubborn to look. The calculations are in Section 3 of https://watervaporandwarming.blogspot.com

        Further work determined that the relative influence at ground level WV/CO2 is closer to 10 than 37. Still enough to put the influence of CO2 on warming to be insignificant.

  9. The trend over two multi-decadal synchronized global stadium wave epochs in the late 20th century. Assuming the pattern of alternate warming and cooling superimposed on an AGW signal persists over the 21st century – there is net warming of about 1 degree C. If anything – there is an expectation that the anthropogenic component will decline.

    https://watertechbyrie.files.wordpress.com/2019/12/temps.png

    Surprises are – however – inevitable. “Fortunately, climate science is rapidly developing the tools to meet this challenge, as in the near future it will be possible to attribute cause and effect in decadal‐scale climate variability within the context of a seamless climate forecast system [Palmer et al., 2008]. Doing so is vital, as the future evolution of the global mean temperature may hold surprises on both the warm and cold ends of the spectrum due entirely to internal variability that lie well outside the envelope of a steadily increasing global mean temperature.” https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2008GL037022

    We may note – based on Palmer and Stevens (2019) – that Tim is still working on this. I wish him Godspeed. 😊

    This is every incentive needed not to hold back on pragmatic responses. “This pragmatic strategy centers on efforts to accelerate energy innovation, build resilience to extreme weather, and pursue no regrets pollution reduction measures — three efforts that each have their own diverse justifications independent of their benefits for climate mitigation and adaptation.” https://thebreakthrough.org/articles/climate-pragmatism-innovation

    • When the UK pulls out of the EU, Tim may not even have a laptop.

    • JCH owes me a million dollars and I am using it to buy Tim a quantum laptop for Christmas.

    • https://en.m.wikipedia.org/wiki/File:Holocene_Temperature_Variations.png

      RIE, Relative to the 40 year decadal chart you post comes a sincere question: if decadal grain was added over the millennia, say to the 10k year chart shown above, wouldn’t that decadal data become noise, and the decadal trend meaningless? It’s a trend until it isn’t.

      And wouldn’t the 10k year “decadal” chart look increasingly noisy and meaningless if added to a 800k year decadal chart, if it were possible to render the below decadally?

      https://en.m.wikipedia.org/wiki/File:EPICA_temperature_plot.svg

      Essentially I’m asking, is it really believed that science is on the cusp of a reliable decadal climate forecast system? Though historical evidence suggests the model could be seemingly right for many decades, centuries even.

    • The other essential point to note concerns the behaviour of the very long series of recorded Nile River data.

      https://www.tandfonline.com/na101/home/literatum/publisher/tandf/journals/content/thsj20/2011/thsj20.v056.i02/02626667.2011.557378/production/images/large/thsj_a_557378_o_f0002g.jpeg

      “Figure 2 shows the annual minimum water level, and the 25-year average, of the River Nile for the years 622–1284 measured at the Roda Nilometer near Cairo (Beran, 1994). Nilometer data led to the discovery of the so-called Hurst phenomenon (Hurst, 1951; Montanari et al., 1997; Koutsoyiannis, 2002) and clearly highlights the huge climatic variability at large time scales (Fig. 2; Koutsoyiannis, 2003). https://www.tandfonline.com/doi/full/10.1080/02626667.2011.557378

      Hurst dynamics involves transitions between states and the persistence of states. Nile basin rainfall is influenced by sea surface temperatures in both the Pacific and Atlantic Oceans. Change there is as shifts in patterns in the spatio-temporal chaos of the globally coupled, turbulent Earth system flow field.

      e.g. http://www.ds.mpg.de/LFPB/chaos

      Dynamical shifts on decadal scales are evident. “One of the most important and mysterious events in recent climate history is the climate shift in the mid‐1970s [Graham, 1994]. In the northern hemisphere 500‐hPa atmospheric flow the shift manifested itself as a collapse of a persistent wave‐3 anomaly pattern and the emergence of a strong wave‐2 pattern. The shift was accompanied by sea‐surface temperature (SST) cooling in the central Pacific and warming off the coast of western North America [Miller et al., 1994]. The shift brought sweeping long‐range changes in the climate of northern hemisphere. Incidentally, after “the dust settled,” a new long era of frequent El Niños superimposed on a sharp global temperature increase begun.” https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2007GL030288

      Shifts in state depend only on current conditions but sum to variability at all scales. Climate may be most simply thought of as a Markov process – with many states and many unknown probabilities. The skill of models – btw – in picking even decadal transitions is such that you might just as well toss a coin. (Mojib Latif, 2015) But if you don’t try – how do you know?
      😊

      • ‘The skill of models – btw – in picking even decadal transitions is such that you might just as well toss a coin. (Mojib Latif, 2015) But if you don’t try – how do you know?”

        The first sentence here makes perfect sense, the second too if it”s tested over a few millennia of observations to evaluate the models efficacy. I wouldn’t want to bet the farm on it until. But this has always been the problem with most models, asking for proof requires ridiculous time scales. Model reliability is as risky as actual climate.

      • This was concerned with reproducing the 1976/77 and 1998/99 climate shifts.

        https://phys.org/news/2013-08-hindcast-capture-long-term-climate-fluctuations.html

      • The near term hindcast is anecdotally interesting, but wouldn’t it be true if an, i.e., volcanic anomaly of the type Dr. Curry describes in this very essay occurred that it would introduce chaos to the system, rendering the hindcast model a moot tool?

      • I find process level models interesting. Fine scales at which fundamental equations can be used. To do so over the whole planet would require 3,000,000 times more computing power – according to Tapio Schneider of Caltec.

        Can volcanoes trigger climate chaos? Like an avalanche that is triggered by a sound or a footfall? They are random and unpredictable.

        https://wordpress.com/media/watertechbyrie.com?s=cat

      • Robert i Ellison: Climate may be most simply thought of as a Markov process – with many states and many unknown probabilities.

        Which you illustrate with a finite Markov chain that has absorbing states?

        That might be “simple”, as you note, but how accurate could it possibly be?

        How exactly does that comport with the long-memory autoregressive model (Hurst)?

        Get real.

      • You probably think that’s clever.

        “These observations of the growth of range of what is now known as the ‘Hurst’ effect stimulated much debate, because Feller showed rigorously that for a very general class of finite variance stochastic processes, the rescaled range grows asymptotically with the record length L as L1/2 4. Many explanations centered on pre-asymptotic effects, but a more mathematically elegant explanation came with the introduction by Mandelbrot, Van Ness and Wallis of fractional Gaussian noise (fGn), the first stationary model which was able to reproduce them. fGn was in itself controversial, however5,6, because it gained the desirable and tractable property of stationarity at the price of introducing infinite-ranged temporal memory or LRD. LRD implies that in order to predict the next state of a system its whole past is needed. This is different from typical dynamical systems whose next state is determined just by the current state. Such systems are called Markovian. This property appeared to many to be inconsistent with the Markovian nature of the equations of motion.” https://www.nature.com/articles/srep09068

      • … the rescaled range grows asymptotically with the record length L as L^1/2… to correct the WordPress change.

      • Robert I Ellison: LRD implies that in order to predict the next state of a system its whole past is needed. This is different from typical dynamical systems whose next state is determined just by the current state. Such systems are called Markovian. This property appeared to many to be inconsistent with the Markovian nature of the equations of motion.”

        The more I read your posts the more I think you don’t understand the mathematics. The process cannot simultaneously have both a “long memory” and “no memory”.

      • You’ll forgive me if I don’t read yours.

      • Robert I Ellison: LRD implies that in order to predict the next state of a system its whole past is needed. This is different from typical dynamical systems whose next state is determined just by the current state. Such systems are called Markovian.

        There is the intermediate case of (vector) autoregressive processes where the entire history is not necessary to predict the distribution of the next state, only some of it. It ought to go without saying that states are never “known”, but only measured or estimated with some error of approximation. The next state is not what is predictable, only the distribution of the possibilities.

        Feller showed rigorously that for a very general class of finite variance stochastic processes, the rescaled range grows asymptotically with the record length L as L1/2

        So what? That does not have anything to do with your previous modeling comments.

      • These are quotes from – ‘A Dynamical Systems Explanation of the Hurst Effect and Atmospheric Low-Frequency Variability’. ‘A Dynamical Systems Explanation of the Hurst Effect and Atmospheric Low-Frequency Variability’ – and in good faith should be acknowledged as such.

        Dynamical complexity is a Markovian process. As in Poincaré’s ‘3-body’ Hamiltonian – subject only to the laws of motion. Or Navier-Stokes in the atmosphere.

        I quoted because I really cannot be bothered with Matthew.

      • Robert I Ellison: I really cannot be bothered with Matthew.

        Thank goodness!

      • Robert I Ellison: ‘A Dynamical Systems Explanation of the Hurst Effect and Atmospheric Low-Frequency Variability’. ‘A Dynamical Systems Explanation of the Hurst Effect and Atmospheric Low-Frequency Variability’ – and in good faith should be acknowledged as such.

        What you like is to assemble large word salads whose individual ingredients are often interesting when considered in isolation. That quote is unrelated to your finite state Markov chain with 2 absorbing states. You eschew coordinating, reconciling, resolving technical details, such as: telling us what the “absorbing states” of the climate system might be, or indeed what any of the “states” in a finite state Markov chain representation of climate. Does a Markov chain have “tipping points”, long memory, bifurcations, or catastrophies? No. What in a Markov chain represents “abrupt” climate change and “non-abrupt” climate change.

        You never come to grips with the reality that the “state” can’t be considered as “known” because it is only estimated/measured with random errors.

      • “The Earth’s climate system is highly nonlinear: inputs and outputs are not proportional, change is often episodic and abrupt, rather than slow and gradual, and multiple equilibria are the norm.” https://www.globalcarbonproject.org/global/pdf/pep/Rial2004.NonlinearitiesCC.pdf

        How accurate is Nile River data that is up to some 1300 years old? Accurate enough for Hurst to discover the pattern described by Rial et al. It was puzzling and gave rise to a statistical explanation involving ‘long range dependence’ (LRD). This was before the paradigm shifting Lorenzian model of oceans and atmosphere as a complex dynamical system.

        “How exactly does that comport with the long-memory autoregressive model (Hurst)?

        Get real.” MM

        It doesn’t. And although auto correlation in regimes is a factor – rescaled range analysis was the method used by Hurst. Details are available online. I have an idea hat Matthew read somewhere about LRD, superficially left it at that – and as is his lamentable habit – again sought to upbraid me for neglecting it. As is usual – he will now attempt to disguise his error with endless obfuscation and personal denigration.

        The Earth system – as I said – may be most simply thought of as a Markov chain where there is a probability of transition to one state or another. The Earth system has many states and unknown transition probabilities. As I said.

        https://adequate.digital/wp-content/uploads/2019/07/Markov-Chain-Attribution-Modeling-1.png

      • Robert I Ellison: The Earth system has many states and unknown transition probabilities. As I said.

        So you did. What are the states? As I asked. Are there absorbing states as in the example at December 26, 2019 at 1:06 am? Are there oscillations within states? Perhaps associated with the earth’s rotation about its axis and the revolution around the sun; or like ENSO?

      • Robert I Ellison: Climate may be most simply thought of as a Markov process – with many states and many unknown probabilities.

        Last question: If it is a Markov process (or even perhaps a Markov chain), is it also deterministic, as you have written of climate before?

      • Robert I Ellison: As is usual – he will now attempt to disguise his error with endless obfuscation and personal denigration.

        More quotes please.

        It doesn’t.

        True. The two approaches make incompatible assertions.

      • I can’t imagine what your purpose is. Or even understand what that means. Has it to do with your assertion that Hurst dynamics have ‘infinite memory’?

        “Lloyd (1967) subsequently coined the term “Hurst Phenomenon” to describe the discrepancy between Hurst’s average value of 0.73 for H and the theoretical value of 0.5 deduced from classical statistical theory…

        In seeking a physical explanation of the Hurst Phenomenon, it is necessary to draw a distinction between
        mathematical/statistical constructs that can reproduce the required behaviour in the rescaled range and the climacogram (variance at aggregate time scales), and an understanding of the physical mechanisms giving rise to the long-term fluctuations/long-term persistence in hydroclimatic time series…

        It also is only natural and perfectly in order for the mathematician to concentrate on the formal geometric structure of a hydrologic series, to treat it as a series of numbers and view it in the context of a set of mathematically consistent assumptions unbiased by the peculiarities of physical causation. It is, however, disturbing if the hydrologist adopts the mathematician’s attitude and fails to see that his mission is to view the series in its physical context, to seek explanations of its peculiarities in the underlying physical mechanism rather than to postulate the physical mechanism from a mathematical description of these peculiarities…

        The fGn model was the first stochastic model proposed in the hydrological literature that could reproduce the Hurst Phenomenon. Its kernel function (11) implies an infinite memory which, as already noted, was challenged by Klemeš (1974) as physically unreasonable.” https://www.tandfonline.com/doi/full/10.1080/02626667.2015.1125998

        The phenomenon discovered by Hurst spawned many attempts to explain the discrepancy between data and theory. All of which I neglected – for simplicity – in favor of the Lorenzian paradigm. How that resolves the tension between a complex dynamical Markovian process and memory in the physical system I will leave to you.

  10. The Wallace-Wells link took me to an American Meteorological Society paper on wind vectors.

  11. Why are we even talking about this? The climate is always changing…always has and always will. Making the planet communist won’t change a thing weather wise…why don’t we talk about making the 3rd world more like the US, free and prosperous.

    • I’ve been arguing for over 15 years that the future is unknown, it always surprises us, that any further warming might be net beneficial – we don’t know – and that damaging our economies in a futile attempt to influence future climate is a very bad approach. Better to strengthen our capacity to deal with whatever future befalls by policies which foster enterprise, innovation, resilience etc, policies which involve smaller government and less regulation, by contrast with the socialist heavy-intervention pro-global bodies policies which the warmistas favour, which essentially will see Western countries succumb to the rising powers of China et al, and which have been rejected in the Trump, Brexit and Australian elections. Long past tiome for a rethink.

      • Yours is the only rational approach. The only reliable climate trend I see is self awareness.

  12. The basic underlying problem is that climate models are CO2 concentration based and not emissions based. ESMs are required to derive atmospheric CO2 concentrations from Carbon emissions. Millar et al. showed conclusively that they fail to do this. That is why models appear warmer than reality for a given carbon budget. The models are running too hot with carbon emissions.

    http://clivebest.com/blog/wp-content/uploads/2017/10/Millar-1.png

    If we can simply stabilise emissions at say 2013 levels then even the BERN model shows a a moderate level of warming for the next 500 years.

    http://clivebest.com/blog/?p=7519

  13. Why are we tying temperature prediction to emissions? Is there any valid reason to believe that our emissions control temperature that has not been falsified by Salby, Harde , and Berry? Has anyone demonstrated any correlation between our emissions and temperatures? If these three scientists are right our emissions don’t even control atmospheric CO2 which is, according to them, nearly entirely naturally controlled mostly by temperature. It seems to me there should be much more effort aimed at falsifying their findings than guessing how much warming we are causing by guessing how much fossil fuel we will burn and guessing how much of that CO2 will add to the atmospheric content. If they can’t be falsified the pursuit of emissions sensitivity or emissions control is entirely wasted effort and the activists that are predicting our doom will continue their perfect record of failure.

  14. This may be of interest.
    I fitted a quadratic and a 1000 year sinusoidal curve to the Harcrut data and the comparison is shown in
    https://drive.google.com/file/d/1CbQ2pOoZjaiqVm5_pY-rnXzcBmrr_SDv/view?usp=sharing
    Not making any predictions but the sinusoidal curve has an amplitude of 2.87 degrees implying a nearly 6 degree range.
    I picked a 1000 year period because of the approximate spacing of warm periods.
    Any comments!!

  15. On the relationship between Atlantic Meridional Overturning Circulation slowdown and global surface warming

    …. Here we present multiple lines of evidence, including a statistical evaluation of the observed global mean temperature, ocean heat content, and different AMOC proxies, that lead to the opposite conclusion: even during the current ongoing global temperature rise a strong AMOC warms the surface. The observed weakening of the AMOC has therefore delayed global surface warming rather than enhancing it.

  16. Judith wrote:
    If you start from an early 21st century baseline, you can subtract 1C from the 3C. Simple . . . now we are down to 2C.

    This is a novel argument and not the way people who think about climate think about climate. They think of total warming since the-preindustrial period. Your method seems to be a way to keep the numbers smaller.

    While we complain about the 21st century ‘weather’ and now call them ‘climate disasters’, few of them have plausible arguments for being associated in any way with manmade climate change.

    This just isn’t true. The recent report Explaining Extreme Events in 2018 from a Climate Perspective found that 18 of 19 events selected to study were affected by climate change.

    https://www.ametsoc.org/ams/index.cfm/publications/bulletin-of-the-american-meteorological-society-bams/explaining-extreme-events-from-a-climate-perspective/

    • Perhaps this is motivated reasoning, that is, wrong.

      The Extreme 2018 Northern California Fire Season
      But….
      California wild fires are less frequent:
      https://cliffmass.blogspot.com/2018/08/california-wildfires-is-global-warming.html

      Anthropogenic Impacts on the Exceptional Precipitation of 2018 in the Mid-Atlantic United States
      Precipitation is a multifactoral phenomenon dependent mostly on dynamics. While models do indicate increased precipitation at all latitudes, extreme events are due to motion much more than the marginal increase modeled. This sounds like chasing the hypothesis, a common problem with observational study.

      Quantifying Human-Induced Temperature Impacts on the 2018 United States Four Corners Hydrologic and Agro-Pastoral Drought
      Of course, if anything, drought has a long term decrease, both in the US as well as globally

      The rest are just similarly made up chasing the hypotheses.

      That some warming follows radiative forcing is sound, because RF is a direct causal link and CO2 is a dominant term.

      But global temperature is not a term in the equations of motion.

      Even if you imagine some factor of temperature, it is usually not the only and certainly not the dominant term.

      Yes, there is global warming.
      But, no, it doesn’t really matter.

      • Data on California: Graphs showing large fires have become more common, and number of acres burned per year since 1950:

        https://www.usatoday.com/pages/interactives/news/california-wildfires-carr-fire-data/

      • Appell, anyone trying to develop a causative relationship between AGW and forest fires is ignoring a host of other variables such as population explosion, exponential growth in wild land/urban interface, arson, accidental human ignition, changes in ecosystem more conducive to fires, poor timber management, lack of land use planning, poorly maintained electrical infrastructure, and on and on. So go ahead and ignore all those possible factors and dumb down the debate by focusing only on AGW. This is the kind of high school logic that destroys your credibility. Besides that, California has a history a mega droughts during the MWP.

        And since California is part of the US, they are most likely part of this

        https://fabiusmaximus.com/wp-content/uploads/2017/12/US-acres-burned-1926-2017.jpg

      • That’s right, nobody but anonymous blog commenters could possibly guess that wildfires might be influenced by factors other than climate change, so that determining the amplifying factors requires minimizing the human factors.

        Warming and Earlier Spring Increase Western U.S. Forest Wildfire Activity
        A. L. Westerling1,2,*, H. G. Hidalgo1, D. R. Cayan1,3, T. W. Swetnam4
        Science 18 Aug 2006:
        Vol. 313, Issue 5789, pp. 940-943
        DOI: 10.1126/science.1128834

        “Here, we show that large wildfire activity increased suddenly and markedly in the mid-1980s, with higher large-wildfire frequency, longer wildfire durations, and longer wildfire seasons. The greatest increases occurred in mid-elevation, Northern Rockies forests, where land-use histories have relatively little effect on fire risks and are strongly associated with increased spring and summer temperatures and an earlier spring snowmelt.”

      • “Westerling et al. found that, in the 34 years studied, years with early snowmelt (and hence a longer dry summer period) had five times as many wildfires as years with late snowmelt. High-elevation forests between 1680 and 2690 m that previously were protected from wildfire by late snowpacks are becoming increasingly vulnerable. Thus, four critical factors—earlier snowmelt, higher summer temperatures, longer fire season, and expanded vulnerable area of high-elevation forests—are combining to produce the observed increase in wildfire activity.”

        https://science.sciencemag.org/content/313/5789/927.full

      • Besides that, California has a history a mega droughts during the MWP.

        Hmm, warming and megadroughts. That seems ominous.

      • “‘They are more and more common because we have more and more fuels,’ said Joaquin Ramirez of Technosylva, an international fire modeling company based in San Diego. …

        Bureau of Land Management fire manager Jeff Tunnell {said} ‘One hundred years of fire suppression is building fuel beds,’ Tunnell said. ‘Almost any year can produce a fire like this one.’”

      • Patrick Gonzalez, National Park Service, climate change specialist presented research attributing the trend of larger fires to policies of fighting the fires, which create thick underlayers of growth, rather than allowing them to burn. ‘We are living right now with a legacy of unnatural fire suppression of approximately a century,’…

      • “Ignitions caused by human activities are a substantial driver of overall fire risk to ecosystems and economies. Actions to raise awareness and increase management in regions prone to human-started wildfires should be a focus of United States policy to reduce fire risk and associated hazards.” Balchas et al 2017 PNAS

    • Do you really think we can compare forest fires acreage in 1926 to today’s? Are there any other factors that might be a factor? Like maybe how much effort was made to suppress fires vs letting them burn?

      • Do you really think we can compare forest fires acreage in 1926 to today’s? Are there any other factors that might be a factor? Like maybe how much effort was made to suppress fires vs letting them burn?

        Exactly – factors other than global warming are much more significant.

      • This Gretaesque mentality of believing that global warming is the root cause of everything, to the exclusion of all other possibilities, is incomprehensible. I understand why she and millions of her fellow adolescents believe with such fervor. They’ve been indoctrinated from preschool onward, to do so. But how did so many adults become such zealots, seemingly incapable of critical thinking. Future generations of social psychologists are going to have a field day preparing case studies investigating the warmist brain.

      • So for 100 years they suppressed fires. They put them out.

        Now the fuel load had passed a tipping point and they can’t put them out.

        Hey, a tipping point. I think that’s a first.

      • jch

        ‘So for 100 years they suppressed fires. They put them out.

        Now the fuel load had passed a tipping point and they can’t put them out.’

        I would equate bushfires, which we rarely get in the UK, with flooding, which we often do.

        At one time there would have been few people to witness flooding. even if they got some, many would just wait for it to pass then carry on as usual, perhaps digging a few ditches or building a wall higher.

        fast forward a few hundred years with many more people, many paying good money to live next to the water on flood plains and most very concerned they should never be flooded because of the financial costs of such an event and the sheer hassle of putting lives back together when everything from cars to photos, fridges to computers have been damaged.

        There are many more people in Australia. Many living in bush fire vulnerable areas and there appears to be a reluctance to control burn as much as they should each year.

        tonyb

      • Flooding. Take Houston. People moved there because it is a good location for a port. It grew, and not because the people wanted to live near the water. It grew because of commerce. Jobs. In 1935 they had a huge flood. Not fun, so they started building infrastructure. Decade after decade after decade. For a time it largely worked.

        Starting with Tropical Storm Allison, the flood control managers in Houston started saying it was beyond them. I was there I heard them.

        They again spent a huge amount of money on flood-control infrastructure. Some of it is still sufficient, the hospital district, but even there it is clearly about to be eclipsed.

        And then somebody will say, they’ve always had flooding. Look at 1935. And what they don’t get is Houston would not even notice a 1935 flood. Their infrastructure, as bad as it is, would largely swallow it whole.

        .

      • cerescokid wrote:
        This Gretaesque mentality of believing that global warming is the root cause of everything

        You keep repeating this and won’t learn. No one is saying global warming is the root cause of everything. They’re saying it’s often a factor that is making some things worse. Capiche?

      • “It is amazing that Aristotle (particularly in his Meteorologica) understood the scale and extent of change much better than some contemporary scholars do:

        Neither the Tanais [River Don in Russia] nor the Nile have always been flowing, but the region in which they flow now was once dry: for their
        life has a bound, but time has not [. . .] But if rivers are formed and disappear and the same places were not always covered by water, the sea
        must change correspondingly. And if the sea is receding in one place and advancing in another it is clear that the same parts of the whole earth are
        not always either sea or land, but that all changes in course of time.5

        Dimitris Koutsoyiannis – Hydrology and change, 2013

        Nothing but a change in perspective will suffice and nothing is less possible for many.

      • Please, Mr. Appell: Capisce? Capito mi hai? Si Lei deve scrivere in un’ altra lingua, meglio studiare un po…

      • Jch

        Apples and oranges. Houston is a young city. It had only 12 inhabitants in 1837 . It now has 2 million in the city and 20 million in the mega region.

        https://en.m.wikipedia.org/wiki/Timeline_of_Houston

        It has grown and grown and I am sure the original founder would not have placed it where he did if he knew 20 million people would crowd in. it is probably not defensible at the scale it now is.

        Tonyb

      • Merry Christmas Tony. The best to you and your family in the new year. You always add so much to the discussion and it’s very much appreciated by me. But I’m naturally partial to the English since my wife discovered my family tree goes back to England in the 1400s.

      • A factor in flooding is that storms now more often sit atop somewhere and poor down. Harvey was the wettest storm in history.

        “Cyclone speeds are found to have decreased globally by ~10% [since 1949], plausibly related to a weakening of the background tropical atmospheric circulation. For landfalling systems, however, which have societally relevant impacts, changes have been more pronounced: storms in the western North Pacific, North Atlantic and Australian regions have slowed by 30%, 20% and 19%, respectively, increasing local rainfall totals and corresponding storm-induced damages.”

        A global slowdown of tropical-cyclone translation speed
        James P. Kossin, Nature volume 558, pages 104–107 (2018)
        https://www.nature.com/articles/s41586-018-0158-3

      • The founders picked the site for Houston because of Allen’s Landing, a rare location where the river was wide enough and deep enough for of boats to maneuver:

        https://i.imgur.com/NclvJxa.png

      • Ceresco kid

        Thanks. A Happy Christmas to you and yours.

        I always enjoy your contributions to. It a shame we produce nothing more than anecdotal information, obviously put together by hoaxers looking to deceive historians hundreds of years in their future.

        It is if course Mayflower 400 next year. I live very close to Plymouth. I checked the manifest of the Mayflower but could not see anyone with the family name of ‘Ceresco kid’ at all :)

        What is your connection with England and when did your ancestors go over?

        tonyb

      • David Appell -“A factor in flooding is that storms now more often sit atop somewhere and poor down. Harvey was the wettest storm in history.”

         “Cuba got hammered by more than 100 inches of rain when Hurricane Flora sat over the island for four days in 1963. And even earlier, in 1909 before hurricanes were named, a storm dropped more than 96 inches of rain on Jamaica. In more recent history, Wilma dumped more than 62 inches of rain on Mexico in 2005 and Hurricane Mitch, blamed for killing more than 11,000 in Central America in 1998, soaked Nicaragua with more than 62 inches, according to records compiled by National Oceanic and Atmospheric Administration forecaster David Roth.”

        https://www.miamiherald.com/news/weather/hurricane/article170512137.html

      • Hi Tony

        My ancestor, George Adams (1620-1696) came from England to America ~1645, and settled in Watertown, Massachusetts. The record has no specific location in England but his grandfather, William Adams ((1555-1624) died in Somerton, Somersetshire, England.
        There are notes in some files that George was arrested for selling liquor to native Americans (I always thought I had an illicit streak in me 😃) and died from a falling rock. His descendants moved to Connecticut then to Vermont before settling in Michigan.
        I’ve noticed a few unusual first names over the generations, such as Friend, Thanks and Thankful
        One of the surprising things that my wife found was that an ancestor of my mother had married an ancestor of my father in Connecticut in the 1700s. I’m sure they never knew since they had no knowledge of their family tree beyond their great grand parents. Both had been deceased many years before we found this out.. They would have gotten a charge out of knowing their family linkage.

      • Ceresco kid

        Interesting, thanks. Someone seems to have done a lot of work researching the name as a quick google brought up lots of links.

        Somerton seems a very nice little town. As the capital of king Alfred’s Wessex it must have been an important place at one time. The grandfathers life exactly spanned the CET reconstruction I did some eight years ago. He lived through some very cold, some very hot, some very dry and some very wet years. Anecdotally of course.

        Tonyb

      • Hi Tony

        Just a generic comment about the hardships of living during those times, especially pre modern medicine, and the health issues they must have faced every day. Even early 20th Century knowledge and practices of doctors make me glad we don’t have to endure the sometimes barbaric treatment that was common during the 1500 to 1800s. On top of that were non heated, non air conditioned living quarters. No thanks.

      • My colonial ancestor showed up in Baltimore, and was among the very first European settlers of the Shenandoah Valley. I can assure you his house was heated. My wealthy Aunt lived in Dallas from 1962 until 2010 without AC. Horrified her friends. Before that she lived in Alaska. Bought a winter coat there, and was still using it when she passed away. Tight with the money.

      • My ancestor turned up in the second fleet – convicted for some petty crime. He was joined by Irish rebels and Scottish enlightenment political prisoners. A heady mix. 😊

      • My wealthy Aunt lived in Dallas from 1962 until 2010 without AC.

        Before that she lived in Alaska.

        Hmmm…..

        Sounds like extreme climate change, self invoked by moving.
        And yet, some how she flourished.
        Climate change is irrelevant?

      • JCH

        My great grandmother lived in a sod hut in North Dakota in the 1800s. She never went without heat….in the summer, and never went without cooling….in the winter.

      • Chief

        I read a good book about the founding of Australia several years ago, The Fatal Shore, by Robert Hughes. What miserable voyages they had. Not exactly first class. Seasick City.

      • “Such is life.” 😊

      • I grew up in the Dakotas. Sod houses are cool in the summer and warm in the winter.

        https://i.imgur.com/yxQM3PI.png

      • JCH

        Relatively. But when they came back, I’m sure they enjoyed one of our cooooool 11,000 Michigan inland lakes in the summer.

    • ” They think of total warming since the-preindustrial period. Your method seems to be a way to keep the numbers smaller.”

      even better she selects a period that starts with La Nina (2000-2001)
      and end in a La Nino

      The rest of the scientific community looked at a variety of periods.
      Prior to 1850, 1880to 1900, etc etc.
      They published papers and methods and data. They showed the sensitivity
      of their choices. they defended their choices at length.

      That’s open transparent and responsible.

      Tossing out 2000-2014 as a defensible baseline is mere rhetoric

      baselining 101 says you want to pick a period that is as long enough
      to reduce noise (~30 years) and one that has a length longer than known natural cycles if possible. (40-60 years) And you want a balance of La nina and EL nino.
      She picked a period that has more El nino than La nina.

      nice trick

      • Surely the common English meaning is that there has been a degree near enough of warming to date. Nice dissimulation.

      • Oh – and reducing ‘noise’ over multi-decadal regimes?

        https://watertechbyrie.files.wordpress.com/2019/12/temps.png

      • Do you know how to calculate the noises’ impact on the slope’s uncertainty?

      • Do you?

        Noise implies randomness. It is not that.

      • Yes, I certainly know how to calculate the uncertainty of a linear trend due to variations of whatever type. It’s pretty easy, actually.

        Noise is not randomness.

      • Then why did you ask?

        A time series is white noise if the variables are independent and identically distributed with a mean of zero. Lets have that almost 1000 years of Nile River data from Dimitris Koutsoyiannis again.

        https://watertechbyrie.files.wordpress.com/2018/05/nile-e1527722953992.jpg

      • Lets have that almost 1000 years of Nile River data from Dimitris Koutsoyiannis again.

        What are the numbers of the time series? A graph is basically useless, especially the ones you gave.

      • The top graph is generated Gaussian white noise – the other is levels in metres – as shown on the graph. The data was originally in Egyptian cubits – equivalent to some 529mm I understand – measured on the Nilometer in Cairo. It’s still there. Here’s another article from the thoughtful hydrologist Dimitris Koutsoyiannis.

        https://www.hydrol-earth-syst-sci.net/14/585/2010/

        The GISSTEMP temperature graph is from Kevin Cowtan’s plotter – and shows 95% confidence limits in accordance with the 2 sigma rule.

        Anything else I can help you with?

      • “Since “panta rhei” was pronounced by Heraclitus, hydrology and the objects it studies, such as rivers and lakes, have offered grounds to observe and understand change and flux. Change occurs on all time scales, from minute to geological, but our limited senses and life span, as well as the short time window of instrumental observations, restrict our perception to the most apparent daily to yearly variations. As a result, our typical modelling practices assume that natural changes are just a short-term “noise” superimposed on the daily and annual cycles in a scene that is static and invariant in the long run. According to this perception, only an exceptional and extraordinary forcing can produce a long-term change. The hydrologist H.E. Hurst, studying the long flow records of the Nile and other geophysical time series, was the first to observe a natural behaviour, named after him, related to multi-scale change, as well as its implications in engineering designs. Essentially, this behaviour manifests that long-term changes are much more frequent and intense than commonly perceived and, simultaneously, that the future states are much more uncertain and unpredictable on long time horizons than implied by standard approaches.”
        https://www.tandfonline.com/doi/pdf/10.1080/02626667.2013.804626

        As for Kevin Cowtan – knock yourself out.

        http://www.ysbl.york.ac.uk/~cowtan/applets/trend/trend.html

        If we all had to abide within the limits of your knowledge – it would be pretty grim.

      • As a result, our typical modelling practices assume that natural changes are just a short-term “noise” superimposed on the daily and annual cycles in a scene that is static and invariant in the long run. According to this perception, only an exceptional and extraordinary forcing can produce a long-term change.

        That’s quite wrong. Climate models solve a boundary problem, not an initial value problem. If you’re studied PDEs you will know what that means. If you haven’t, it means that climate models don’t specify, or depend on, every annual/quarterly/monthly/daily bump up and down, it means they balance energy at each time interval. After all, we aren’t much interested in tracking every little up and down in the weather — what we really want to know is the ECS, and the TCR. Natural variations sum to zero for these, so we don’t care what temporary factors like solar irradiance comes to (climate isn’t very sensitive to changes in solar irradiance anyway, <~ 0.1 K/(W/m2)), and volcanic eruptions, and AMOs and PDOs and ENSOs and all these other things mentioned that don't determine the climate end state.

      • Such a rote response that is wrong in so many ways. Natural variability is not random and does sum to zero on timescales less than millennia. That was the point. But I am a little bored now. Perhaps I will return to this repetitious trivia tomorrow. Perhaps not. Hopefully someone more interesting will come along.

      • Natural variability is not random and does sum to zero on timescales less than millennia.

        Ok, and usually quicker than that.

      • David Appell, You repeat the misrepresentation that climate is a boundary value problem. Perhaps it is you who doesn’t understand PDE’s.

      • A typo – natural variation is not random noise on a signal. It does not sum to zero.

        As for models – perhaps we can do an experiment to disprove or support Davis’s internet meme – I mean hypothesis. Run a model with different combinations of feasible initial conditions 1000’s of times and see how quickly solution trajectories converge.

        https://watertechbyrie.files.wordpress.com/2014/06/rowlands-fig-1-e1515528276356.png
        https://www.nature.com/articles/ngeo1430

        Perhaps we should try that again while expecting a different outcome?

      • I’m a little confused. You say in your post that models essentially don’t care about enso, amo, pdo, solar irradiance… etc. since they all nullify each other given a large enough time frame.

        So, are you saying that after disregarding all of the other cyclical forcings, you’re left with only GHG’s as the true driver of climate change?

    • The whole purpose of thinking about warming since pre-industrial revolution is just motivated reasoning by motivated science to make the numbers big. What citizens obviously care about is how much warming compared to right now.

  17. Nic calculated the observationally-based values of TCRE to be 1.05°C.

    How can TCRE be as low as 1.05 C (three significant digits, really?) when warming is already at 1.0 C and atmospheric CO2e hasn’t even increased by 50% yet? And warming has been held down by anthropogenic aerosols?

    • Nic’s presentation is on youtube. Search for Lewis climate. He does a very good job as usual of dotting all the i’s.

      It’s pretty hard to argue that the historical record will underestimate TCR which is after defined in terms of the temperature increase with gradually increasing forcing.

      • We are *at* 1.05 C of warming. And CO2 hasn’t increased by 50% yet, let alone doubled. Such a conclusion is illogical.

      • Such naive picking of end dates is of little value compared to Nic’s much more careful balancing of volcanic forcings for beginning and end dates, Please view the video. There is some good stuff in there about the carbon cycle too.

      • Thanks, but I’d rather look at the paper.

      • Such naive picking of end dates….

        What end dates?

      • David, Are you awake this evening? You cite 1.05 C increase which I assume is from 1880 to 2019 or 2019. This number is not scientifically meaningful and I’m surprised you throw it out without any scientific basis whatsoever and then draw an unjustified conclusion,

      • Both NOAA and GISS show 1.04 C of warming since 1880. HadCRUT4 shows 0.96 C since then.

      • You still don’t get it. This number is not meaningful because there are lots of extraneous forcings to consider such as volcanic forcing and internal variability which Lewis is careful to eliminate.

      • dpy6629 commented:
        You still don’t get it. This number is not meaningful because there are lots of extraneous forcings to consider such as volcanic forcing and internal variability which Lewis is careful to eliminate.

        How many of those have persisted for 140 years (since 1880)? Not averaged to zero over that time?

      • David: IMO it’s no use to argue without reading the related papers or looking at the linked video.

      • stevenreincarnated

        David, according to Lund 2006 the Gulf Stream has been accelerating since the LIA. That is a climate forcing that covers a much longer time period than you are asking for.

    • The assumption that all 20th century warming was anthropogenic is unsafe.

      e.g. https://www.nature.com/articles/s41612-018-0044-6

    • 1Tt C = 3.7 Tt CO2 and when I went to school reporting an expect value to some precision was usual when the uncertainty in the estimate was also reported.

    • frankc: I wrote I’d rather read the paper than sit through a 1-hr video that would, for understanding, require reading the paper anyway.

      But I don’t see how volcanic eruptions could have had a lasting force from 1880-2019.

  18. nobodysknowledge

    On the relationship between Atlantic Meridional Overturning Circulation slowdown and global surface warming
    Levke Caesar, Stefan Rahmstorf and Georg Feulner, 2019.
    This is a repetition of the Real Climate Police Force (Rahmstorf and Mann) debunking Chen and Tung by using a strange AMOC proxy. They used a proxy which was defined from SST, and which had nothing to do with overturning. How many Sverdrups did ocean currents change at different depths? And how did temperatures change at different depths? Of no interest to Real Climate Police. It was just some idea of Rahmstorf that heat from the atmosphere couldn`t be turned down into ocean.

    • Yes, their paper has been peer review and accepted, but the work is so flimsy you can tear it down with a short blog comment.

      Get real.

      • Pal reviewing at its best, pal!

      • Pal reviewing at its best, pal!

        So you know who reviewed their paper? Or is this just a made-up excuse to reject the paper — any paper, really, that you don’t like — without even having to read its title, let alone having to plow through the paper? It keeps you safely in your cocoon.

    • So was Chen and Tung. So what?

      AMOC appears to be slowing in data from the 26 degree north array – Smeed et al 2014, Smeed et al 2018.

    • From memory, the SST fingerprint method they used reconstruct AMOC variability originated in a paper by an author outside the RC group, not that it matter at all.

    • Appell’s cocoon being the notion that government climate science and peer review can be assumed to resemble the the real thing.

  19. Reblogged this on Climate Collections.

  20. Thanks, Judith.

    Happy holidays to you and yours.
    Bob

  21. Ireneusz Palmowski

    A strong wave appeared on the boundary of the stratosphere and the mesosphere in the region of the polar vortex. The disturbance will slowly reach the lower stratosphere.
    https://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_WAVE1_MEAN_OND_NH_2019.png

  22. “They calculate the amount of warming based on TCRE:

    “The amount of warming the world is projected to experience can be pretty closely approximated solely based on cumulative CO2 emissions. This relationship between temperatures and cumulative emissions is referred to as the transient climate response to cumulative carbon emissions, or TCRE”

    The TCRE versus statistics

    https://tambonthongchai.com/2018/05/06/tcre/

    https://tambonthongchai.com/2019/09/21/boondoggle/

  23. David N. Hauseman

    If heated rocks found around ancient camp fires become polarized and can point to the magnetic north at the time of the camp fire, then what about the magnetized rocks if the earth’s crust, and how will the crust react when we have a flop on the poles? Will this reaction be seem as man-made?

  24. “Well, is anyone predicting another solar maximum in the 21st century, similar to what we saw in the mid/late 20th century? No . . . rather, there are some predictions for solar cooling in the mid 21st century.”

    Predictions for solar cooling have typically got the relationship between solar and the AMO backwards. Lower sunspot numbers in the 1970’s has nothing to do with the cold AMO phase, it was very strong solar wind states driving a positive NAO/AO regime which cooled the AMO strongly in the early to mid 1970’s. I can safely predict a very similar period of strong solar wind states through 2042-2045, by the Jovian configurations ordering it. It is the quadrature series of the three inner Jovian bodies which has dominated the 69 year frequency of the AMO for the last two AMO cycles.

    “While we can’t predict future solar, volcanic and long term ocean oscillation activity, we can expect multidecadal periods in the 21st century where the external forcing tends towards cooling and also the ocean oscillations support cooling, reduced Greenland ice melt, etc.”

    The prediction for the next coldest AMO years is above, based on empirical evidence of the drivers, and the understanding that stronger solar wind states drive colder ocean phases. I also have the only empirical findings on the ordering of sunspot cycles and centennial solar minima, which show that this centennial minimum only effects cycles 24 and 25. The Salvador solar model which Nils Morner adopted is based on Tallbloke plagiarising my findings on the role of Uranus, and completely misapplying them, it has no utility.

    https://www.linkedin.com/pulse/major-heat-cold-waves-driven-key-heliocentric-alignments-ulric-lyons/

  25. Joseph Ratliff

    Reblogged this on Quaerere Propter Vērum and commented:
    Came from the discussion on Twitter, and that discussion reinforces the idea that Twitter is not real life.

    Excellent analysis, Dr. Curry.

  26. Great work all and a promising new year ahead!

    By way of facilitating communication, here is my crude (but free) textbook — “Issue Analysis: An Introduction to Issue Trees and the Nature of Complex Reasoning.”

    http://www.stemed.info/reports/Wojick_Issue_Analysis_txt.pdf

    It explains the logical form of complex issues like climate change, which is a tree structure that I discovered and named the Issue Tree. It is also about drawing diagrams of issue trees. These can be helpful, but the big thing is just to understand the structure you are dealing with. This tree like structure is a primary reason why complex issues are hard to deal with.

    The basic point is that when you say something in the climate change debate, there are multiple responses. And most of these responses have multiple responses, and so on. Thus the number of things to be said increases exponentially with level of detail. The issue “blows up” wherever you touch it.

    Also, speaking and writing are linear sequences of sentences, which do a poor job of traversing a complex issue tree. This is what I call “the jumping problem” and it is explained in the book.

    The book is crude because it was just for my personal use when I taught issue analysis at Carnegie Mellon. Plus it was done on an ancient mechanical device called a typewriter.

    If anyone wants to actually dig into this stuff I will be happy to help.

    Onward!

    David

    The Climate Change Debate Education Project
    http://ccdedu.blogspot.com

  27. Bah humbug. It is the same talking points repeated endlessly from positions of cultural identity. Not counting the weird science of would be giants pushing their Diogenic tubs around the ideas marketplace – ideas around climate have congealed into views manifestly at odds with uncertain and complex science.

    https://www.thoughtco.com/thmb/OPVbpZGAK1P3TQN5HTZsEJ02W3s=/768×0/filters:no_upscale():max_bytes(150000):strip_icc():format(webp)/maslow-s-hierarchy-of-needs–scalable-vector-illustration-655400474-5c6a47f246e0fb000165cb0a.jpg

    The future does not depend on climate science – although I would the commend the evolving science of Earth systems. The future is what we want for ourselves, our communities, culture, civilisation, the planet and its wild places. Economic growth, democracy and innovation are the way forward – at the price of cyberpunks and really smart phones. Water sensitive cities reduce impacts on the water cycle. Increasing production efficiency uses less energy and materials and produces fewer harmful by-products. Higher agricultural productivity with precision farming and intensive rotational grazing allows land to return to forest,woodlands and wildlife and conserves downstream environments. Both build resilience to flood and drought. The question of fire regimes is not changes in frequency and intensity but what is optimal for fire ecology. Progress in energy technology enables a transition to cost competitive, low carbon energy sources – reducing risk in what complexity science suggests is a system sensitive to change. With economic growth many societies are more peaceful and productive than ever in history. There is a realistic view of human capacities to solve human problems and to conserve and restore ecologies at the same time.

    • Quite so. By focussing so much on one issue, which may never be a serious problem and about which we can do little, the Western world is shooting itself in the foot while the rest of the world exploits our obsession.

    • The future is what we want for ourselves, our communities, culture, civilisation, the planet and its wild places. Economic growth, democracy and innovation are the way forward

      There is going to be a few meters of sea level rise no matter what. That’s going to seriously impact many coastal cities around the world. Bailing them out is going to be a drag on economic growth.

      • “There is going to be a few meters of sea level rise no matter what. That’s going to seriously impact many coastal cities around the world. Bailing them out is going to be a drag on economic growth.”

        This needs to be looked at in relative terms – i.e. what is the cost of protection/periodic repair compared to value? For example, Miami city authorities are planning to spend a few hundred million $ in the next couple of decades on flood protection measures, but compared to real estate values this really is peanuts. When you look at the numbers, the proposed measures cost a few percentage of the annual INCREASE in property tax revenues. That’s also why expensive land reclamation and flood protection schemes are viable in the Netherlands – the high value of the land easily pays for them. What is the likely impact of sea level rise on economic growth in the Miami area? Probably negligible! The countervailing factors dwarf any effect.

        The real problems are going to be in coastal regions in the developing world, but here the future is likely to reflect the past where 99% of the harm arises from poverty and dysfunctional government, rather than weather or climate. When a tropical storm hits the coast in North America it results in single digit or a few tens of deaths, there is only temporary economic disruption, and life is back to normal in days, weeks or months at worst. When a similar storm hits the Philippines tens of thousands die, mostly because of serious and sustained civic breakdown, and the impact is still felt years or even decades later. If 99% of the problem could be mitigated, which it certainly can, such events would matter considerably less even if the frequency/severity increased. There is another advantage of tackling the problems of climate change from this side of the equation: the cost is relatively modest and we know how to do it!

      • Since sea-level rise is gradual, those affected have lots of time to move.

      • @bfjcricklewood | December 27, 2019 at 5:51 am |

        “Since sea-level rise is gradual, those affected have lots of time to move.”

        Ditto with temperatures. If you live in the Northern hemisphere and wish to experience the Armageddon of one degree of climate change likely by the end of the 21st century it requires no imagination. Jump in your car and drive approximately 100 miles south and get out. It will be THAT bad! In the Southern hemisphere it will be around half that distance north.

        Is it possible humanity will survive this existential threat? Probably no one will notice amid their other daily concerns.

    • A great frustration of my life is that ‘climate’ with wild and speculative notions has sucked the oxygen out of broader discussions of legitimate human aspirations to build prosperous and healthy communities in vibrant landscapes. Far too often it is camouflage for a nihilistic world view. A myopic vision involving narratives of moribund western economies governed by corrupt corporations collapsing under the weight of internal contradictions – leading to less growth, less material consumption, less CO2 emissions, less habitat destruction and a last late chance to stay within the safe limits of global ecosystems. It is completely at odds with reality and the hierarchy of human needs. Only rich economies can afford clean air and water, health, education, conservation and new productive systems and technology.

      In our coupled, nonlinear world there is chaos and risk – but two metres of sea level rise is a dog whistle not worth considering – 500 years at current rates. There is much more immediate promise. There has been decades of progress on nitrous oxides, CFC’s and aerosols in the west – this will accelerate as economies grow in the developing world. And they will be much better placed to cope with surprises. Ongoing decreases in carbon intensity and increases in efficiency and productivity fuels growth. As does technical innovation across sectors – energy, transport, industry, residential and agriculture and forestry.

      Carbon sequestration in soils has major benefits in addition to offsetting anthropogenic emissions from fossil fuel combustion, land use conversion, soil cultivation, continuous grazing and cement and steel manufacturing. Restoring soil carbon stores increases agronomic productivity and enhances global food security. Increasing the soil organic content increases water holding capacity and creates a more drought tolerant agriculture – with less downstream flooding. There is a critical level of soil carbon that is essential to maximising the effectiveness of water and nutrient inputs. Global food security, especially for countries with fragile soils and harsh climate such as in sub-Saharan Africa and South Asia, cannot be achieved without improving soil quality through an increase in soil organic content. Wildlife flourishes on restored grazing land helping to halt biodiversity loss. Reversing soil carbon loss is a new green revolution where conventional agriculture is hitting a productivity barrier with exhausted soils and increasingly expensive inputs.

      Increased agricultural productivity, increased downstream processing and access to markets build local economies and global wealth. Economic growth provides resources for solving problems – conserving and restoring ecosystems, better sanitation and safer water, better health and education, updating the diesel fleet and other productive assets to emit less black carbon and reduce the health and environmental impacts, developing better and cheaper ways of producing electricity, replacing cooking with wood and dung with better ways of preparing food thus avoiding respiratory disease and again reducing black carbon emissions. A global program of agricultural soils restoration is the foundation for balancing the human ecology.

      https://watertechbyrie.files.wordpress.com/2015/11/solar-city-maree-faulkner.jpg
      Solar City – by a great friend – Maree Faulkner

      The blue, green, red and orange of the solar city signposts endless new possibilities for the human ecology. Great and shining cities rising in a song of renewal. A great, global spanning civilisation forged this century and nested in a profusion of nature. Populations replanting and replenishing in a triumph of human ecology in the Earthly garden – a sound foundation for our next steps to the stars. Great art and great music flourishing – song and poetry inspiring and amusing. Technologies proliferate and will be directed to the task of bringing our lives into balance with the world. The great task of renewing the world and empowering its peoples will bring a resolution that releases immense energies. What seem like dire and insoluble problems of the moment will fade like midnight forebodings in the morning light. Take heart and celebrate – as these “bioneers” are – the advent of this new world with laughter, songs and dance.

      https://watertechbyrie.files.wordpress.com/2015/11/bioneers.png

      Merry Christmas
      😊

      • All your frustrations — “legitimate human aspirations to build prosperous and healthy communities in vibrant landscapes” — were present long before climate change.

        And 2 m of SLR will happen long before 500 years. It’s already costing Americans billions of dollars.

      • Well then we had better get busy and adapt to sea level rise. It has been rising since the end of the little ice age. This is a policy issue, not a mitigation issue. Right now the government subsidizes building on coastlines with Federal flood insurance. We should start by eliminating that. We spend very little on coastal defenses and in some areas they are needed. Land subsidence is at least as big a problem as sea level rise. Perhaps injections into the subsurface layers could partially address this. We have no plan and no research on this so far as I can tell.

        It is tiresome when alarmists hark on sea level without suggesting anything practical to help people deal with it.

      • A perfect example of climate strawman monomania sucking the oxygen out of broader discourse. Americans – btw – have saved $11 trillion in the past 10 years with frakked gas alone. They can afford a few billion on blue carbon.

      • dpy6629 commented :
        Well then we had better get busy and adapt to sea level rise. It has been rising since the end of the little ice age

        Where’s your data on that?

        What I’ve seen is that sea level rose about 1 meter in the 5000 years before the industrial era, an average of 0.2 mm/yr. It’s now rising about 4.3 mm/yr, over 20 times faster. And accelerating.

      • dpy6629 commented :
        Well then we had better get busy and adapt to sea level rise.

        Miami Beach is spending $400 M to do so, partly paid by taxpayers. NJ has spent $300 M of taxpayer money to buy out homeowners, called their Blue Acres program. $30 M of taxpayer money has been spent to move Newtok, AK, with much more to come. $48 M awarded to residents to move 99 residents off Isle de Jean Charles, Louisiana. $15.67 B in coastal home values lost along the US east and Gulf coast (https://www.citylab.com/environment/2019/11/property-value-flood-mississippi-bay-st-louis-climate-change/602476/).

      • Where you are responsible for lives, disaster planning and emergency response -caution is the name of the game. We have been planning, designing and building for this for decades. Largely in response to erosion and storm surge. Including planned retreat. We moved our local hospital from the beachfront to a couple of kilometres inland for instance. Critical infrastructure is built above the 500 year inundation level. We base that on historic data and add a safety margin. Only the most significant infrastructure is protected – houses fall into the sea. New development in erosion prone zones doesn’t happen. This is just run of the mill practical engineering.

      • Source?

      • Your supposed $11 T in savings from shifting from coal to NG — told you so!) was money Americans should never have had to pay in the first place, including with their lives. It was the product of coal companies, who have gotten off scot free. The US Clean Air Act Amendments of 1990 provided $2 T/yr in annual benefits through 2020, though with a large uncertainty, preventing 160,000 deaths in 2010 alone. I guess those are “straw man deaths,” huh?

        http://www.eenews.net/assets/2011/03/01/document_gw_03.pdf

        “How the Clean Air Act Has Saved $22 Trillion in Health-Care Costs,” Alan H. Lockwood, The Atlantic 9/7/12.
        http://www.theatlantic.com/health/archive/2012/09/how-the-clean-air-act-has-saved-22-trillion-in-health-care-costs/262071/

        Any conservative who isn’t an environmentalist isn’t being true to their ideology.

      • “This pragmatic strategy centers on efforts to accelerate energy innovation, build resilience to extreme weather, and pursue no regrets pollution reduction measures — three efforts that each have their own diverse justifications independent of their benefits for climate mitigation and adaptation. As such, Climate Pragmatism offers a framework for renewed American leadership on climate change that’s effectiveness, paradoxically, does not depend on any agreement about climate science or the risks posed by uncontrolled greenhouse gases..”

        https://thebreakthrough.org/articles/climate-pragmatism-innovation

        https://watertechbyrie.files.wordpress.com/2017/06/hele-e1550170804379.jpg
        https://watertechbyrie.files.wordpress.com/2019/06/hele.png

        Careful – you are getting sillier David.

      • We base that on historic data and add a safety margin.

        Now you are in a new era, where SLR is accelerating.

        You sound like the North Carolina legislature, who made it illegal to plan for sea level rise beyond the linear trend.

      • We start with this and add freeboard, erosion setbacks and 2 metres for storm surge. This is presumed to be the 1% inundation level. Which part of practical engineering didn’t you understand?

        https://coastadapt.com.au/sea-level-rise-information-all-australian-coastal-councils#QLD_LIVINGSTONE

      • I don’t understand much about practical sea level engineering, of course. But I do understand that 2 m storm surges will keep getting higher and more frequent. I understand that sea level rise is accelerating, globally. And I understand that I don’t see any considerations of that in your engineering.

      • As I said last time – where information is shared and not considered – and instead there is some oddball talking past people – then it is a great waste of time. It typically results in swathes of your comments being deleted. For what purpose is any of it?

      • A flame in the wind and extinguished just as quickly. Comments disappear left, right and center. His point was coal and mass death – and some indecipherable objection to America saving $11 trillion over 10 years using frakked gas. Problem solved – at least for new coal in the rest of the world. Sea level rise costing billions. Conservative calculations, safety margins and risk management. Infrastructure at least at the conservative 1% inundation level. Coastal designs explicitly made with climate change in mind. Lives are at stake and engineers cannot wing it. Then there are mangroves and saltmarsh. These fast accreting systems are the best and cheapest way to attenuate wave setup and storm surge. Sediments are oxygenated to 10mm deep – below that organic matter is preserved in anoxic conditions. Making them great places to sequester carbon.

        I cannot at all see what he is objecting to. It all seems misdirection and ultimately tantrums. Perhaps he is more interested in ‘social and economic transformation’ that dare not say its name. Perhaps it is the moderate alliance that makes him and his alarmist ilk irrelevant. Perhaps it is just the bear scenario. You don’t have to be smarter than Yogi when chased by a bear – just smarter than the other guy.

      • Appell’s comment – “What I’ve seen is that sea level rose about 1 meter in the 5000 years before the industrial era, an average of 0.2 mm/yr. It’s now rising about 4.3 mm/yr, over 20 times faster. And accelerating.”

        4.3mm per year – really

        The satelite records shows 3.2- 3.4mm per year
        the tide gauges show 1.5-1.7mm per year.
        The satelite records only show acceleration due to the dubious downward adjustment in early years to match the tide gauges.

        In order to believe the downward adjustment was valid, you have to believe the tide gauges were valid for 120+ years but somehow are invalid only in the last 15 years.

        https://oceanservice.noaa.gov/facts/sealevel.html
        https://oceanservice.noaa.gov/facts/sealevel.html

      • David

        Your comment at 7.52

        Why on earth would you average out 5000 years of sea level change? It varied enormously and rose and fell a number of times, sometimes slowly sometimes quickly.

        Go back just a few thousand years more and sea level rise was up to 6 feet in a century when temperatures were warmer by up to 2 degrees over the modern day. mind you, that comes from those well known sceptics at the national geographic.

        https://www.nationalgeographic.com/magazine/2012/12/doggerland/

        Tonyb

      • This is sea level where I live – and projected increases under RCP 6.0. The latter is derived essentially by smoke and mirrors. Or to mix the metaphor – turtles all the way down. But engineers need a baseline over reasonable planning periods.

        https://watertechbyrie.files.wordpress.com/2019/12/sea-level-yeppoon.png

        There are lots of ways to do way better than RCP 6.0 – a high emission scenario. Including the population growth moderating smart development goals of the Copenhagen Consensus.

        https://www.copenhagenconsensus.com/

        Is this a future for nuclear power? We will find out in the next decade as dozens of advanced nuclear prototypes come online.

        https://media.wired.com/photos/5df2e38e6c75590008cd8e5a/master/w_1600%2Cc_limit/Science_Oklo_Forest_Day.jpg
        https://www.wired.com/story/the-next-nuclear-plants-will-be-small-svelte-and-safer/

      • Re the link in the Tonyb post above on the flooding of Doggerland pls note the date as 8000BP (the 8k2BP) not the date stated in caption as 8000BC.
        In a link in a post of mine below, the 8k2BP event appears in three separate proxy sources, giving better indication of events. Doggerland adds a different perspective (from geological change – subduction more than sea level rise, as in the Med), as does the 5k2 event (Piora oscillation – from geology and archaeology)

      • Tonyb

        Have you ever commented on these utterly ridiculous sea level rise arguments?

        https://i.imgur.com/DmCuLQj.png

        https://i.imgur.com/ERbREkV.png

      • Fort Denison – originally Mattewanye, and – colloquially since the early penal days – Pinchgut Island.

        https://www.psmsl.org/data/obtaining/rlr.annual.plots/65_high.png

        There is a cyclone forming off the northern coast and an anti-cyclone off the south-east coast.

        https://earth.nullschool.net/#current/wind/surface/level/orthographic=-212.74,-26.77,791/loc=175.711,-16.534

        A spinnaker run down the east coast. Can a super-maxi yacht win overall race honours?

        https://www.youtube.com/watch?v=fxjL7tvsPKs

        Patterns spun up by the Southern Annular Mode and ENSO on a rotating planet. The distinction between weather and climate is less convincing by the day. We cam likely attribute the lack of sea level rise at Mattewanye to secular variability in ocean and atmospheric circulation over the 20th century.

      • ENSO to multi-decadal time scale changes in East Australian Current transports and Fort Denison sea level: Oceanic Rossby waves as the connecting mechanism

        6. Conclusions and future thoughts

        This paper demonstrates a number of interesting findings. First, we have shown that annual running mean filtered monthly sea-level variations recorded at the Fort Denison tide-gauge in Sydney Harbour are closely related to baroclinic EAC transport anomalies across 33.5 S (r1⁄40.58, significant at the 99% confidence level, at the 9-month lag) as determined in a linear, reduced- gravity shallow-water ocean model forced with NCEP/NCAR reanalysis wind stress anomalies. …

        The connection between regional- and large-scale wind stress forced Rossby waves and the variability and trends in EAC transports and Fort Denison sea level affords excellent potential for ocean forecasting as well as large scale climate monitoring and observing systems.

      • Yes – I think that’s what I said. But with centennial to millennial variability – and positive SST/albedo feedback in the eastern Pacific adding to 20th century warming. The latest Pacific Ocean climate shift in 1998/2000 is linked to increased flow in the north (Di Lorenzo et al, 2008) and the south (Roemmich et al, 2007, Qiu, Bo et al 2006) Pacific Ocean gyres. Roemmich et al (2007) suggest that mid-latitude gyres in all of the oceans are influenced by decadal variability in the Southern and Northern Annular Modes (SAM and NAM respectively) as wind driven currents in baroclinic oceans (Sverdrup, 1947).

      • JCH

        It’s not an argument, it’s called observational data. The last link you provided failed miserably in disputing the long term trend in Sydney. Or are you suggesting there is a phantom messing around with the Tidal Gauge? But then you would have to take on the Tidal Gauges in other locations around the world. And the recent studies finding no or insignificant acceleration in the rates.

      • There is absolutely nothing about Fort Denison the disputes the global oceans rose at a rate of 4.48 mm/yr over the last ten years.

        https://i.imgur.com/gt8Ve0u.png

      • Except this.

        https://tidesandcurrents.noaa.gov/sltrends/sltrends_station.shtml?id=680-140

        Updated to 2018. It looks like the last 5 years have dropped like a rock. That phantom, I guess.

      • Ceresco kid

        the truble is that you and jch are compating apples and oranges. looking at a global change-whether for sea levels or tenperatures misses out the nuances.

        Many sea levels -as you demonstrate-are falling not rising, although the movement of the ground needs to be taken into account. Similarly one third of the world is cooling but that nuance is lost by looking at a global average.

        its a bit ;like looking at global gdp. those countries in substantial surplus need to take very different measure to those who are suffering a recession.

        Similarly, those places with a sea level locally falling do not need to take the same measures as those where sea level is rising rapidly.

        The UK Temperature has been static for 2 decades yet our elite are running round like headless chickens terrifying our children into the process.

        I hope jch will engage on local issues rather than looking at global ones all the time which -although important and interesting-do not show the whole picture.

        tonyb

      • cerescokid

        An update is needed for 2019 but the 3/4 Year hiatus in sea level rise can be seen here

        http://sealevel.colorado.edu/content/2018rel1-global-mean-sea-level-time-series-seasonal-signals-retained

        (note; seasonal signals retained-removal can be made pressing the link)

        tonyb

      • Satellite-era rate of sea level rise has been creeping upward all year, and will likely continue creeping upward in 2020. The fact is, since the PDO started regime shift to positive, the rate of sea level rise has been on a bender.

        So calling of it a stasis is just absurd.

  28. Judith,

    As Boblo noted above, the Wallace-Wells link still seems to be wrong.

    I think the link you may have intended is:
    http://nymag.com/intelligencer/2019/12/climate-change-worst-case-scenario-now-looks-unrealistic.html

    Merry Christmas and all the best for the coming year!

    Dave

  29. Dr. Curry,

    This is what I projected in 2009 in my book, Table 5 page 60, 2.06 degrees C.

  30. If someone can explain why the last interglacial was warmer and sea levels were higher, and why those factors are not in play in the current interglacial, then I might consider agw as an explanation for current trends.

  31. The WUWT figures are courtesy of Renee Hannon, and I find them very illuminating. Useful to compare and contrast with other information graciously supplied by other sources. (In my case especially so since they corroborate same and similar information obtained earlier. And always as long as its genuine, based on my own digging on the source).
    The second link from my site is such a comparison of three sources with more detail. “the devil [of it all] is in the detail” – of a deeper sort-; (note the 7k2 and 5k2 events that I added, abrupt climate changers)

  32. Hi Judith, 2 degree since preindustrial agrees with a Business as usual SRES A1B under TCR of 1.33
    https://klimaathype.files.wordpress.com/2018/11/temp_sres.png

  33. Photon Powered, High Side, Sideways Racer
  34. stevenreincarnated

    Lund and Curry 2006 Florida Current surface temperature and salinity variability during the last millennium “Variable solar irradiance apparently pace shifts in Florida Current salinity during the last millennium, implying the transport of salt into the North Atlantic is sensitive to modest changes in solar forcing on centennial time scales.”

    Sorry folks, we were taken in by a solar forced change in ocean heat transport. Please excuse the last few decades of hysteria.

  35. The Sydney-Hobart yacht race starts today – a Boxing Day tradition. Conditions are perfect for run downwind close to the coast. It may all come down to tactics and luck in the last beat around the bottom of Tasmania.

    http://www.bom.gov.au/fwo/IDY00061/IDYAR005.aus.20191225_2100.png

    Oh – and the first tropical low of the season is spinning up west of the Coral Sea.

    https://earth.nullschool.net/#current/wind/surface/level/overlay=mean_sea_level_pressure/orthographic=-170.03,-0.43,575/loc=177.164,-11.444

  36. As someone who observes the weather and weather satellite images I can say that Climate change Crusade is a real hoax. But as people are trying to disprove their claims of temperature rises and other patterns they are creating so many disasters through weather engineering like HAARP and making people all over the world suffer. Recently I have observed over 6 cyclones in the Indian subcontinent and none of them touched the land. They know how to create it and steer it and change its nature. Looks like they are perfecting a technology. But a few of them went out of control and resulted in severe floods and deaths of many humans and animals and destruction of nature and property. The more you fight against them the more they create trouble for the innocent people to prove their point. One more thing is that about 98% of the population is walking zombies. It’s a waste of time and energy fighting for the zombies. Only hope is at least there is one powerful world leader who believes that it’s all a hoax. Yes… it is a clever scam to plunder your money by making people believe that humans are responsible for climate change.

  37. Pingback: Judith Curry: 3°C or 1°C? - The Global Warming Policy Forum (GWPF)

  38. Concerning natural variability and oscillation.
    Proxy reconstructions of the AMO and the ENSO-PDO clearly show a widely varying time period from a quarter century to almost a century:

    https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2005GL024804

    https://www.clim-past.net/6/1/2010/cp-6-1-2010.pdf

    https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2008GL034475

    This argues against strong external (e.g. astrophysical) forcing, suggesting instead either weak forcing (with complex emergent waveform) or internal feedback-driven oscillation.

  39. Tethys (Saturn’s satellite) Effective Temperature Complete Formula Te.tethys is:
    Te.tethys = [ Φ (1-a) So (1/R²) (β*N*cp)¹∕ ⁴ /4σ ]¹∕ ⁴

    Tethys’ orbital period is 1,887 802 days
    Tethys’ sidereal rotation period is synchronous 1,887 802 days
    N = 1/1,887 802 rotations/per day
    R = 9,5826 AU, 1/R² = 1/9,5826² = 0,01089 times lesser is the solar irradiation on Saturn than that on Earth. The same is on Saturn’s satellite Tethys
    So = 1.362 W/m² is Solar constant
    Tethys’ albedo, atethys = 0,80 ± 0,15 (bond)
    Let’s assume atethys = 0,70
    Tethys is a heavy cratered planet, Tethy’s surface irradiation accepting factor Φtethys = 1
    Cp.tethys = 1 cal/gr oC , Tethys’ surface is ice crust
    The density of Tethys is 0.98 g/cm³, indicating that it is composed almost entirely of water-ice.
    β = 150 days*gr*oC/rotation*cal – it is the Rotating Planet Surface Solar Irradiation Absorbing-Emitting Universal Law constant
    σ = 5,67*10⁻⁸ W/m²K⁴, a Stefan-Boltzmann constant
    So we have: Tethys’ effective temperature Te.tethys
    is:
    Te.tethys = {1*(1-0,70)1.362*0,01089(W/m²) [150*(1/1,887802)*1]¹∕ ⁴ /4*5,67*10⁻⁸(W/m²K⁴) }¹∕ ⁴ = 87,48 K
    Te.tethys = 87,48 K is the calculated.
    And below is the measured by satellites
    Tsat.tethys = 86 ± 1 K

    http://www.cristos-vournas.com

  40. The Action Now! People have no interest in the distinction between 3 and 1 degree of warming. Hence the following:

    A year of ineffective climate madness looms (my latest)
    By David Wojick

    https://www.cfact.org/2019/12/26/a-year-of-ineffective-climate-madness-looms/

    The year 2019 saw the rapid rise of climate hysteria, but as the saying goes: “You ain’t seen nothin yet.” Now that the hysteria is firmly established and well organized, it is sure to get bigger and louder. But I see very little coming from it except the noise, as long as skeptics keep up the good fight.

    This is especially true in the U.S. Presidential race, which is climate policy-wise by far the biggest thing going on in the world. Many of the Democrat candidates are going to try to ride the hysterical wave to victory. Their winning is not likely.

    My take is the further left you go the fewer votes you get, and these folks are going far left on climate. In my view the only viable candidate in the pack is Biden and he may not be crazy enough to get the nod. Nor can he beat Trump, so things are looking good on that front.

    Another big unknown is what the hysterical demonstrators are going to do. Bigger marches? More disruption? (The police now have glue remover.) Or maybe something we have not seen before, hopefully not more violent. I am sure the advocacy insider email traffic is buzzing over this. (Maybe some new wacky signs. “I don’t want to die!” seems to be catching on.)

    For that matter, will the hysterics endorse specific candidates for the Democrat nomination? Or perhaps get active in specific Congressional races? They might even form their own party (but Greta Thunberg cannot run, more’s the pity). Political action seems like the logical next step for the extremists, which could further destabilize the green movement, given that most of the political action groups are moderates.

    There are lots of other climate crunch points in progress as well. In a recent meeting the EU failed to come up with a more ambitious emission reduction goal for 2030, despite its hysterical leadership calling for one.

    The next meeting on this proposal will be in June. No doubt we will see lots of “Action Now!” marches and demonstrations then, but ambition may well be lacking at the EU national member level, which is all that counts. Several countries are already missing their 2020 target and there are anti-action demonstrations too boot, from yellow vests to farmers and coal miners. The political leaders are running a bit scared of this stuff.

    The UN will have several semi-summits, leading up to the grand COP 26 in Glasgow, beginning in November. Given what happened in Madrid’s COP 25 we are likely to witness the progressive collapse of the entire UN climate action process.

    The UN’s Paris Accord process is entirely too slow and compromising for the Action Now! hysterics to tolerate. This will be especially certain if the Action Now! hysteria builds during 2020, which is very likely. That the mythical $100 billion a year promised to the developing countries does not show up in Glasgow will compound the collapse.

    Then too there is a lot going on at national levels around the world. Especially promising is the rapid rise of new populist parties that oppose the drastic actions demanded by the Action Now! radicals. Left wing hysteria typically generates a conservative reaction. How could it not? Angry mobs are dangerous.

    Mind you I expect to see a lot of meaninglessly symbolic green action in response to the hysterical noise-making. This includes toothless declarations of “climate emergency” and pointless promises of zero emissions by far off 2050. Politicians promising the impossible, to be delivered in the far distant future, do no harm. Hence their popularity.

    My definition of winning the great climate change debate is that no serious harm is done by the alarmists. While I expect an escalating crescendo of hysterical shrieking during the course of 2020, the reason will be that my side is winning and the loud side is losing.

    As things stand now, skeptics have a chance to win big in 2020, but we must keep the pressure on. Hold your nose, plug your ears, and hit them hard. You ain’t seen nothin yet.

    Please share this strategic analysis.

    David

  41. This is a 2019 Australian poll conducted for the Lowy Institute – not known for their radicalism – by the Social Research Centre at the Australian National University. Review their methodology by all means.

    https://www.lowyinstitute.org/sites/default/files/Poll%20-%20Global%20Warming%20-%20With%20Question.png
    https://lowyinstitutepoll.lowyinstitute.org/files/lowyinsitutepoll-2019.pdf

    Preaching to the skeptic peanut gallery is a lost cause. Doing it again and again and expecting a different result is downright hilarious.

  42. Ireneusz Palmowski

    Climate change is associated with changes in ionizing radiation in the stratosphere in an alternating magnetic field.
    https://www.esa.int/Applications/Observing_the_Earth/Swarm/Our_protective_shield
    “Although, it was noted17,18 that Sporer minimum (1460–1550) is not present in our summary curve, which instead during the same period of time shows a standard grand cycle, the previous one to the modern grand cycle (17–21 centuries). Zharkova et al.17,18 reasonably argued that Sporer minimum is an artifact of the strongly increased at that time background radiation on the Earth caused by the explosion of a very close (about 600–700 light years) supernova Vela Junior occurred in the southern sky. The radiation induced by this explosion for this period has not been considered in the background radiation required for the carbon dating method19,20 that could shift the dates by a few hundred years.”
    https://www.nature.com/articles/s41598-019-45584-3

  43. I think your base period is likely to bias calculation of CS low due to the recent weak solar cycle.

  44. Ireneusz Palmowski

    This much is clear: due to what it is, a red supergiant, Betelgeuse will eventually explode as a supernova. It is roughly 550-650 light-years away (parallax measurement is uncertain due to its size) and when it goes supernova, it will be spectacular.

    The question is, is what we are seeing now just some behavior of a variable star, or the indications it is shrinking and about to explode?
    https://wattsupwiththat.com/2019/12/26/is-betelgeuse-in-orion-about-to-explode-in-a-supernova/

  45. Sea level rise calcs also don’t reflect the likely transfer of water from ocean to land by increasing precipitation and biological activity.

    http://archive.news.iupui.edu/releases/2016/02/drylands-global-greening.shtml

    https://phys.org/news/2018-01-discrepancies-satellite-global-storage.html

  46. Pingback: Two more degrees by 2100! | Climate Etc.

  47. Enceladus (Saturn’s satellite) Effective Temperature Complete Formula Te.enceladus is:

    Te.enceladus = [ Φ (1-a) So (1/R²) (β*N*cp)¹∕ ⁴ /4σ ]¹∕ ⁴

    Enceladus’ orbital period is 1,370218 days
    Enceladus’ sidereal rotation period is synchronous 1,370218 days
    N = 1/1,370218 rotations/per day
    R = 9,5826 AU, 1/R² = 1/9,5826² = 0,01089 times lesser is the solar irradiation on Saturn than that on Earth. The same is on Saturn’s satellite
    Enceladus
    So = 1.362 W/m² is Solar constant
    Enceladus’ albedo, aenceladus = 0,81 ± 0,04 Bond
    Enceladus is a heavy cratered planet, Enceladus’s surface irradiation accepting factor Φenceladus = 1
    Cp.enceladus = 1 cal/gr oC , Enceladus surface is mostly covered by fresh, clean ice.
    Enceladus is mostly covered by fresh, clean ice, making it one of the most reflective bodies of the Solar System. Consequently, its surface temperature at noon only reaches −198 °C (−324 °F), far colder than a light-absorbing body would be. Despite its small size, Enceladus has a wide range of surface features, ranging from old, heavily cratered regions to young, tectonically deformed terrains.
    β = 150 days*gr*oC/rotation*cal – it is the Rotating Planet Surface Solar Irradiation Absorbing-Emitting Universal Law constant
    σ = 5,67*10⁻⁸ W/m²K⁴, a Stefan-Boltzmann constant
    So we have: Enceladus’ effective temperature Te.enceladus
    is:
    Te.enceladus = {1*(1-0,81)1.362*0,01089(W/m²) [150*(1/1,370218)*1]¹∕ ⁴ /4*5,67*10⁻⁸(W/m²K⁴) }¹∕ ⁴ = 79,61 K

    Te.enceladus = 79,61 K is the calculated.

    And below is the measured by satellites
    Tsat.mean.enceladus = 75 K

    http://www.cristos-vournas.com

  48. Pingback: 2019 – The End of a Decade When Climate Change Alarmism Tipped Abruptly Into Climate Crisis Hysteria | Climate Scepticism

  49. Don’t forget that land warming is about 1.3 times global warming. So 3 C of warming is 4 C if you live on land, as most of us do. If you’re American, that equals 7 F. Now tell me that’s no big deal.

    • There is also the natural variability that occurs on both sides, minus, and, while not allowed around here, also plus.

    • Don’t forget that land warming is about 1.3 times global warming. So 3 C of warming is 3.3 C average if you live on land at equilibrium in thousands of years time.
      Would need to run fossil fuels for 350 years increasing to force a 0.1C per decade increase. So David believes in a near inexhaustible supply of fossil fuel?
      David forgot that water is 2/3 of earth surface so at equilibrium in a 3C global warming 2/3 minimum to the oceans. Oceans 2.85 C land 3.3 C.
      While waiting to get there Oceans take a lot longer to warm up due to massive ocean atmosphere mass, Most, 9/10 of heat into oceans so atmospheric temp remains closely tied to the very slowly increasing ocean temp.
      The 6F that might result would be much lower in the tropics and much higher at the poles.
      London might warm 6F. Wouldn’t that be luverly?

  50. Pingback: 2019 - La fine di un decennio in cui l'allarmismo dei cambiamenti climatici è precipitato bruscamente nell'isteria della crisi climatica

  51. I notice Ren on arctic temps. Too early to speculate yet.
    Too early.

    • Oh go ahead. It won’t hurt a bit to be fantastically disappointed yet again.

      • So you say. I hate being fantastically disappointed.
        So , No.
        Will wait for at least 1 week of ice growth before speculating.
        Third warmest UAH? Quite a surprise. Was hoping for 5th.

  52. Pingback: Weekly Climate and Energy News Roundup #392 – All My Daily News

  53. Pingback: Weekly Local weather and Power Information Roundup #392 – Daily News

  54. Dimitris Poulos

    Scientists have not yet addressed the issues on climate science I have proposed. As I have shown in my papers the solar irradiance AND solar wind determine the temperatures in earth. People usually forget to look at solar wind when they look at the sun. They only take into account the solar activity and solar irradiance. As I have shown the solar wind is decisive. It manipulates the geomagnetic field and cloud covering. Temperatures oscillate according to the sun. By adding the AMO index oscillation (that counts for internal system variability) to the two solar constituents, we get an extremely accurate temperature projection. As soon as AMO turns negative we shall experience a strong cooling. That should rather be more than one degree cooling by 2100.

  55. Dimitris thank you. What you have found opens the door for a new era in the climate prognosis.
    http://www.cristos-vournas.com

  56. Dimitris Poulos

    Christos thank you for your kind words.

  57. George Reagan

    It’s all guess work. It’s NOT like building a prototype and testing it under lab conditions and then testing in actual conditions before going to actual use in the field. But, HEY, we need to keep all of the crackpots employed on ClimateGate, climate change, social/racial/ economic/ environ-mental JUSTICE or the would be flipping all beef burgers at the local greasy spoon.

  58. jason morrow

    Thank you Dr,Curry for the sanity you bring to the climate issues.I am just an ordinary citizen,carpenter,woodworker,father and grandfather.My family looks to me to bring peace and calm to their world so they might forge their lives with as much correct information as possible.
    So thank you for all you do.

  59. Pingback: De klimaat-apocalyps was gepland! (uit Doorbraak) – Seniorenforum

  60. Pingback: Two More Degrees by 2100! | US Issues

  61. Pingback: A Challenge to Evangelical Climate Scientist Katharine Hayhoe

  62. From Berkeley Earth, whom Curry previously co-authored research with:

    http://berkeleyearth.org/wp-content/uploads/2020/01/2019_Projection-1024×577.png
    “Since 1980, the overall trend is +0.19 °C/decade (+0.34 °F/decade) and has changed little during this period. By continuing this trend, we can make a rough guess of how the near-future climate may develop if the forces driving global warming continue at their present rate.
    As shown in the chart, several recent years have had temperatures more than 1 °C (1.8 °F) above the average temperature from 1850-1900, often used as an estimate of the pre-industrial climate. The Paris Agreement on Climate Change aims to keep global temperature rise to well below 2 °C (3.6 °F) and encourages parties to strive for warming of no more than 1.5 °C (2.7 °F). At the current rate of progression, the increase in Earth’s long-term average temperature will reach 1.5 °C (2.7 °F) above the 1850-1900 average by around 2035 and 2 °C (3.6 °F) will be reached around 2065. The increasing abundance of greenhouse gases in the atmosphere due to human activities is the direct cause of this recent global warming. If the Paris Agreement’s goal of no more than 2 °C (3.6 °F) warming is to be reached, significant progress towards reducing greenhouse gas emissions needs to be made soon.”

    https://web.archive.org/web/20200204160710/http://berkeleyearth.org/2019-temperatures/

    The forces driving current warming predominately anthropogenic: human-made increases in greenhouse gases. See, for example:

    https://www.carbonbrief.org/guest-post-why-natural-cycles-only-play-small-role-in-rate-of-global-warming
    DOI: 10.1175/JCLI-D-18-0555.1
    DOI: 10.1126/sciadv.aao5297

    So Hausfather + Ritchie are right: we’re on pace for ~3°C of surface warming, with ~2°C of 21st century warming, and ~1°C of industrial-era warming from before the 21st century. Thus Curry is wrong. One way to tell she is wrong is that the observed ~0.2 °C/decade 21st century warming rate is something she predicted wouldn’t happen:

    “However these data end up being analyzed, the trend since 1997 is very small, much smaller than the decadal trend of 0.2C that we have been led to expect by the IPCC for the early part of the 21st century.”
    https://judithcurry.com/2012/10/21/sunday-mail-again/

    “This pause in warming is at odds with the 2007 IPCC report, which expected warming to increase at a rate of 0.2 degrees Celsius per decade in the early 21st century. The warming hiatus, combined with assessments that the climate-model sensitivities are too high, raises serious questions as to whether the climate-model projections of 21st century temperatures are fit for making public policy decisions.”
    https://judithcurry.com/2014/10/09/my-op-ed-in-the-wall-street-journal-is-now-online/

    “Yes, but the very small positive trend is not consistent with the expectation of 0.2C/decade provided by the IPCC AR4. In terms of anticipating temperature change in the coming decades, the AGW dominated prediction of 0.2C/decade does not seem like a good bet, particularly with the prospect of reduced solar radiation.”
    https://judithcurry.com/2012/02/07/trends-change-points-hypotheses/

    One confirm that 21st century surface warming rate of ~0.2 °C/decade at:

    http://www.ysbl.york.ac.uk/~cowtan/applets/trend/trend.html
    https://www.esrl.noaa.gov/psd/cgi-bin/data/testdap/timeseries.pl
    https://climexp.knmi.nl/selectindex.cgi?id=someone@somewhere
    http://climexp.knmi.nl/select.cgi?id=someone@somewhere&field=cmst

  63. Is 3 C warming over the 21st century now the ‘best estimate’? A reframing of how we think about climate change over the 21st century, and my arguments for 1 C.

    Approximately fifteen years ago, I placed a prediction on the Long Bets website:

    http://longbets.org/181/

    A 2001 Wigley and Raper paper in Science (or “Science”) predicted that the most likely warming from 1990 to 2100 would be 3.06 degrees Celsius. I predicted that the most likely warming from 1990 to 2100 would be 1.2 degrees Celsius, and that my prediction would be more accurate than the Wigley and Raper prediction in Science (or “Science”).

    P.S. The reason I add the parenthetical (or “Science”) is that, despite Wigley and Raper’s ridiculous assumption that all the IPCC Third Assessment Report scenarios had equal probability of occurrence, there has to my knowledge not been a single follow-up paper in “Science” that attempted to more accurately assess likely emissions scenarios. (My “most likely” scenario predicted global CO2 emissions peaking in 2030, and that total global CO2 emissions over the course of the 21st century would be 712 GtC, versus the Wigley and Raper prediction that the “most likely” outcome was rising emissions all the way to the year 2100, with total emissions of 1385 GtC.)

    https://markbahner.typepad.com/random_thoughts/2017/07/mark-bahner-vs-wigley-and-raper-science-2001-vs-ipcc-rcps.html