Hurricanes and global warming: 10 years post Katrina

by Judith Curry

We anticipate that it may take a decade for the observations to clarify the situation as to whether the hypothesis has predictive power.Curry et al. 2006

My first substantive post at Climate Etc. was Hurricanes and global warming: 5 years post Katrina. I recall spending two weeks (!) working on that post (its a very good post, if I say so myself).  I no longer actively research this topic, although I do keep up with the literature.

In this post, I review the recent observationally-based literature on the topic of climate change and hurricanes, and in particular address the issue of sorting out natural variability from human caused climate change in terms of impacts on any changes in hurricanes; an issue that i raised in my 2006 publication Mixing politics and science in testing the hypothesis that greenhouse warming is causing a global increase in hurricane intensity.

For a quick update, see an an article by CarbonBrief that includes some interviews with hurricane/climate scientists.  Also  note a blog post by Kerry Emanuel at the CCNF Climate change and Hurricane Katrina: what have we learned?

Let me begin here with an update from some of the  antagonists in the 2005/2006 hurricane wars –  new papers by Chris Landsea and Phil Klotzbach (protégée of Bill Gray) and Greg Holland.

Landsea and Klotzbach

Phil Klotzbach and Chris Landsea have a new paper in press at J. Climate:

Extremely Intense Hurricanes: Revisiting Webster et al. (2005) after 10 Years

Abstract. Webster et al. (2005) documented a large and significant increase in both the 23 number as well as the percentage of Category 4-5 hurricanes for all global basins from 24 1970-2004, and this manuscript examines if those trends have continued when including 25 ten additional years of data. In contrast to that study, as shown here, the global frequency of Category 4-5 hurricanes has shown a small, insignificant downward trend while the  percentage of Category 4-5 hurricanes has shown a small, insignificant upward trend  between 1990 and 2014. Accumulated Cyclone Energy globally has experienced a large  and significant downward trend during the same period. We conclude that the primary  reason for the increase in Category 4-5 hurricanes noted in observational datasets from 1970 to 2004 by Webster et al. was due to observational improvements at the various global tropical cyclone warning centers, primarily in the first two decades of that study.

Their main figure:

Slide1

Their argument for ignoring data prior to 1990:

The mid to late 1970s heralded the advent of geostationary coverage around much of the world with the launching of GOES-1, 164 Meteosat-1, and GMS-1. However, the North (and South) Indian Ocean lacked direct geostationary satellite data until 1989 with the launching of Meteosat-5 (Knapp and Kossin 2007). Consequently, the archived best track data from JTWC only reports one Category 4-5 hurricane from 1970-1989 for the North Indian Ocean, whereas, during the most recent twenty-year period from 1995-2014, 13 Category 4-5 hurricanes have been observed. Landsea et al. (2006) identified several missed Category 4-5 hurricanes before 1990, which were instead considered to be weaker TCs. After the advent of geostationary satellites, techniques we  re developed and refined for interpreting the intensity from satellite imagery. In particular, the Dvorak Technique – a position and intensity pattern recognition scheme – was first developed in the early 1970s for visible imagery (Dvorak  1975) and later revised to include infrared imagery (Dvorak 1984). The adaptation of this tool globally became standard during the 1980s once the Regional Specialized Meteorological Centers were established for monitoring and forecasting tropical cyclones  (Velden et al. 2006). In addition, operational responsibility for the northeast Pacific basin  shifted from the Weather Service Forecast Office, Redwood City, California, to the  National Hurricane Center following the 1987 season, which appears to have caused an  artificial jump in 1988 in analyzed intensities between the two agencies (Todd Kimberlain, personal communication, 2015). Finally, the demise of extensive aircraft  reconnaissance missions in the Northwest Pacific basin in 1987 likely led to a non negligible impact upon analyzed intensities. The efforts within the IBTrACS project  (Knapp et al. 2010) have led to global TC data sets, but, while these data are now easily  available, there has yet to be an internationally agreed-upon standardized global TC  intensity database.

JC comment:  The debate on the increase in % CAT45 hinges on whether the data from 1985-1989 is of useful accuracy.  I concur that the global intensity prior to 1980 isn’t useful, but through the 1980’s the data become increasingly reliable.   Missed Indian Ocean CAT45 should not have an overwhelming affect on the statistics, since Indian Ocean tropical cyclones constitute only 25% of global TCs.  Prior to 1988, Northwest Pacific Basin intensities were arguably MORE accurate (aircraft reconnaissance) – NW Pac tropical cyclones constitute about 40% of global TCs.

Note: here is an email response from Klotzbach specifically regarding 1985-1989:

A couple of primary issues with that pentad are:

1) Aircraft reconnaissance ended in the NW Pacific in 1987. There were probably some issues going purely to satellite data in 1988 that are hard to quantify. JC comment: Quantitatively, potentially how big a deal is this?  Worth throwing out 5-10 years of data?

2) Even more problematic were TC classifications in the NE Pacific prior to 1988. The National Weather Service office in Redwood City, CA was responsible for that basin until 1988, and their estimated intensities are quite suspect. For example, correlations between large-scale parameters such as SSTs show very little correlation with ACE over the period from 1971 (when consistent NE Pacific observations began) and 1987, while they show robust correlations with ENSO from 1988-on.  JC note:  NE Pacific constitutes 17% of global TCs.  What is the worst case scenario as to ho much this could impact the global stats?

Well even if you accept PK’s rationale for throwing these data out, there shouldn’t be a problem with adding 1988 and 1989 back into the dataset.

In my previous post, I included this diagram (updated through 2009):

graph1First point:  I don’t like the pentad analysis; especially given the shortness of the period considered; plotting every year is more defensible from a statistical perspective.

Second point:  If the idea is to test a relationship between increasing %CAT45 and increasing SST, then you need to look at the period when the SST is increasing.  Starting at 1990, you only see a relatively small increase in SST (well somewhat larger if you are buying the Karl et al. analysis).  Every effort should be made to add back the data from the 1980’s, with appropriate corrections and/or error bars.

Holland and Bruyere

Published in Climate Dynamics:

Recent intense hurricane response to global climate change

Abstract. An Anthropogenic Climate Change Index (ACCI) is developed and used to investigate the potential global warming contribution to current tropical cyclone activity. The ACCI is defined as the difference between the means of ensembles of climate simulations with and without anthropogenic gases and aerosols. This index indicates that the bulk of the current anthropogenic warming has occurred in the past four decades, which enables improved confidence in assessing hurricane changes as it removes many of the data issues from previous eras. We find no anthropogenic signal in annual global tropical cyclone or hurricane frequencies. But a strong signal is found in proportions of both weaker and stronger hurricanes: the proportion of Category 4 and 5 hurricanes has increased at a rate of  25–30 % per “C of global warming after accounting for analysis and observing system changes. This has been balanced by a similar decrease in Category 1 and 2 hurricane proportions, leading to development of a distinctly bimodal intensity distribution, with the secondary maximum at Category 4 hurricanes. This global signal is reproduced in all ocean basins. The observed increase in Category 4–5 hurricanes may not continue at the same rate with future global warming. The analysis suggests that following an initial climate increase in intense hurricane proportions a saturation level will be reached beyond which any further global warming will have little effect.

Main Figure:

Slide1Holland and Bruyere accept the TC intensity data since 1975 as being reliable, using indirect assessments such as the Kossin et al. satellite reanalysis and global landfall data.

JC comment:  This is an interesting analysis, and addresses the attribution issue in a novel way. However, IMO the main challenge to their analysis is the issue of internal variability.  Here is what they have to say on this topic:

There is a possibility that some of the observed trend arises from internal tropical cyclone variability that has aliased into the 35-year period used here. However, we consider that a substantial contamination from internal variability is highly unlikely. By using global mean temperatures in the development of the ACCI, we have explicitly excluded all but external forcing factors from this aspect of the analysis. There could be an influence of 11-year sun cycles or impulsive events such as volcanoes, but we suggest that the period chosen is too long for these to have a cumulative effect on the trend.

For global hurricane proportions, we are aware of no association with internal variability such as the Pacific Decadal Oscillation or similar. The consistent regional Cat 4–5 relationshipwith globalACCI argues for the regional changes observed here being unaffected by relative processes and thus due largely to global changes.

I am unconvinced that natural internal variability is a non-issue over the past 35 years.

Natural variability

To address the issue of natural variability, see these plots from tweets by Ryan Maue.

Global Accumulated Cyclone Energy (Maue):

Slide2North Pacific ACE vs PDO (Maue):

Slide1

Emanuel’s Potential Dissipation Index for North Atlantic (Maue)

Slide8

 

2015 – a record breaking year

If you mostly pay attention to N. Atlantic hurricanes, you may have missed the records being broken elsewhere around the globe.  These records are summed up by the following tweets from Phil Klotzbach:

Northern Hemisphere Cat 4-5 hurricanes by Aug 16 (Klotzbach)

Slide5

Northern Hemisphere ACE through Aug 24 (Klotzbach)

 

 

Slide4

Most of the action is in the NW Pacific; Phil Klotzbach has blogged at Weather Underground on the records being set by the 2015 NW Pacific TC season. The North Atlantic is having a quiet year so far, as predicted (El Nino).

Tweets from Phil Klotzbach:

Northern Hemisphere ACE remains at record levels (400 ACE) thru 8/19, ~90 units ahead of 2nd place (310 ACE) (1971).

NW Pacific ACE at record high levels (257) thru 8/17 – ~30 ACE greater than 2nd place (2002).

Historic central/eastern Pacific outbreak- 3 major hurricanes at once for the first time on record!

Hurricane Jimena is the 13th Cat. 4-5 TC of the 2015 N Hemis season, 4 more than any other year to date since ’71

Thru 8/27, the average 1981-2010 NW Pacific season had 3.3 Cat 3+ typhoons. In 2015, the NW Pacific has already had 9 (273% of normal!).

N Hemis ACE remains at record levels thru Aug 24 (435 ACE) – over 100 ACE units ahead of 2nd place (1971 – 321 ACE).

75% of all hurricanes forming in the Northern Hemis in ’15 have reached Cat. 4-5, breaking record set in 2007 (64%).

JC comment:  Looks like 2015 will significantly change the statistics of the assessment of %CAT45.

Chris Landsea on U.S. landfalls

Chris Landsea recently published a comment that has a useful updated plot of U.S. landfalls.Slide1

The figure shows that there has been a small, statistically insignificant downward trend in the frequency of U.S. [landfalling] hurricanes in this century-long time series.  Instead, the record is dominated by Interannual to decadal scale variability, with the busies periods occurring in the 1910s, the 1930s to the 1950s, the mid-1980s, and the mid 2000s, while the quietest periods are seen during the 1920s, the 1970s to the early 1980s, the early 1990s, around 2000 and the last few years.

JC reflections

It seems that the principal scientists involved in this research are saying pretty much the same thing they were each saying 10 years ago.10 additional years of data have helped a little bit in sorting all this out, but losing 1-2 decades of data on the front end of the data series definitely hinders our ability to settle the disagreements over this.

SST is hypothesized to play a role in intensity, NOT frequency.  Hence metrics such as ACE and PDI, while interesting in their own right, don’t really address the issue of intensity directly.  The metric %CAT45 seems to have held up as the metric that is increasing, although the amount of the increase depends on what period you consider – starting the time series at 1990 misses much of the late century temperature increase and the apparent increase in %CAT45 during the 1980’s.

The issue of natural variability seems perhaps overemphasized by Landsea and underemphasized by Holland.  In any event, how to sort out the natural from anthropogenic causes of the TC variability remains the key issue in all this. In Curry et al. (2006), I wrote:

A number of natural internal oscillations of the atmosphere-ocean system have a large impact on SST (e.g. El Nino, North Atlantic Oscillation).  However, decadal-scale oscillations tend to be specific to each ocean basin and are often anti correlated from one basin to another.

Since this paper was published, we now understand much more about the natural models of variability on decadal to multi-decadal time scales.  These oscillations (e.g. the AMO, PDO, NGPO, etc) influence tropical cyclone activity through organizing circulation systems in the atmosphere and ocean that influence SST, wind shear, atmospheric humidity, etc.  Most significantly, a number of these oscillations are synchronized and interact in a coherent way (stadium wave).  Hence, a coherent multidecadal global signal in tropical cyclone activity associated with the stadium wave would not be a surprise.  Unfortunately, 25 years (or even 45 years) of data is not sufficient to identify and understand such a signal.

So apart from the challenges of detecting an increase in %NCAT45, the issue of attributing any increase to natural variability versus  human caused global warming remains outstanding.   Both are almost certainly contributing to any increase; the  question is of course whether human caused warming dominates over natural variability. Given the large interannual and interdecadal variability (and the relatively short data record, it isn’t possible with our current understanding to tease out the fractional attribution.  The method proposed by Holland and Gruyere is interesting, but it somehow needs to better account for natural internal variability.

So . . . another 10 years, what will that bring?   Well, this time I won’t predict that this will be sorted out in another 10 years.

 

 

 

237 responses to “Hurricanes and global warming: 10 years post Katrina

  1. maksimovich1

    SST is hypothesized to play a role in intensity, NOT frequency.

    That would be consistent with south pacific cyclones ,where there is little change in SH sst in the 21st century.

  2. Judith, you are too polite to these people.

  3. “There is a possibility that some of the observed trend arises from internal tropical cyclone variability that has aliased into the 35-year period used here. However, we consider that a substantial contamination from internal variability is highly unlikely.”

    “contamination”?

    What an appalling word choice.

    What they mean is:
    “The trend we have identified may be entirely natural. But we prefer not to contemplate that.”

    Seems to me this hurricane science is no different to temperature science – the consensus scientists will only start to grapple with attribution after they’ve been dragged kicking and screaming to do so by the skeptic community.

  4. Is LandFall data better?
    What is the trend of Cat 4 & 5 storms on land (landfalls)?

    Please correct me if I am wrong but don’t records of storm landfalls give us a much longer history and consistent measure of storm activity? So even if we don’t have solid wind speed records landfalls leave other traces in proxies and historical accounts.

  5. Tried to understand hurricane trends a bit. Started with dinner table knowledge, as my father was among other things a USAF meterologist who contributed to the development of weather radar at the ‘Sea Girt Inn’ (US Army Wearther Research Lab, Fort Monmouth NJ, then top secret) and a command pilot on B-29 weather recon missions off Guam 1948-1950, the 54th WRS ‘typhoon chasers’. He once brought back a B-29 with the tail bent 17 degrees out of true by turbulence. Quite a saga. They scrapped the plane for parts. Bent useless by a typhoon.
    Well, I utterly failed to understand hurricanes in relation to global warming despite nearly three years part time trying. Warmer water should intensify, but NHC itself says warmer water also relates to stronger wind sheer which dissipates (like Danny, Erika this year).
    This post provides much personal research consolation, since Judith does not understand yet either. And she is several magnitudes better educated.

    It is OK to ‘dunno’. We just dunno about this, as the dueling papers show.
    Except in the CAGW meme, where all the science is supposedly settled.

    A prediction. IF CAGW makes it to IPCC AR6, this will either not be discussed at all, or glossed over. Like the pause was in AR5, essay Hiding the Hiatus.

  6. Of course, in comparing past with recent events a major effort is being made to reproduce the means of observation and REPORTAGE of past events, right? Otherwise, those graphs and numbers are pretty futile, aren’t they? Can’t compare satellites with oranges.

    To compare the early 19th century with the early 21st you would need to use only the means and extent of 19th century observations for both periods. The 19th century can’t know and copy our standards, so we have to know and copy theirs.

    The shabby and vague comparisons thus produced would contain more truth than all the faux precision of statistics which happily ignore the limitations of historical knowledge.

    • You have a big point on observational uncertainty. Back before satellites and hurricane hunters, TC would be reported by ships–iff they survived.
      In the present airplane era, they were sometimes investigated if ships detected them, or if they were detected on long recon flights for other purposes (e.g. some of my fathers). Only in the short sat era do we detect them ‘all’. Maybe. And then freak out over Danny and Erika. Erika was predicted by Ryan Maue to be pathetic, dissipating over Hispaniola due to wind sheer and elevation. He was right, but I am still in a South Florida flood/storm watch even though the ‘worst’ past several hours ago, and was much less worse than predicted. Krimminy.

      • Rud

        We are fortunate that none other than Daniel Defoe thoroughly investigated the extent of Britain’s first properly recorded Hurricane in December 1703

        https://en.wikipedia.org/wiki/The_Storm_(Daniel_Defoe)

        Not only could we expect the waters around Britain to be cold in December (currently they are16C on 31st August) but we could expect them to be exceptionally cold as we were just emerging from the coldest phase of the LIA. Fortunately we can see from my chart showing the instrumental record of the time that there had been a decade long period of authenticated severe cold

        So Hurricanes do not seem to need warm water. From my own research I would say some of the worst storms on records have occurred during the periods of substantial cold weather.

        tonyb

      • Rud, so much comes down to detection and reportage. 1975’s June remains second only to Tip (1979) in strength, yet, in an earlier era, June may well have been ignored or even unknown. Down the memory hole, as a serf might say. Even Tip may not have left its mark without eg those 60 air reconnaissance missions. Nobody would ever have missed dam-busting Nina (up to 200,000 dead?) in the same year as June, though it was well short of June in strength.

        It’s good we’re likely to know so much more about each major storm in our era. It’s not good if we imagine that something is new or unprecedented because we detect it. Not good at all. The scientific definition of that is “absence of horse sense”.

    • mosomoso

      Lets not forget the reasons the Met Office was set up in 1859 by Fitzroy after a ferocious storm. It was to draw together the previously extremely patchy observations and try to create a means to provide storm warnings.

      http://www.metoffice.gov.uk/news/in-depth/overview

      We can trace some storms over hundreds of years and Hubert Lamb wrote a very good book on ‘Great Storms of North West Europe’ which drew together many of these over the last 500 years. How many more were missed due to lack of observations?

      So, as you say in comparing modern and past numbers we need to establish the same observational methodology which is impossible.

      However, we can say that we have always had great storms and we need to look at the great sweep of history and not just focus on the last few decades before we come to believe they are worse or more frequent than they used to be.

      tonyb

      • I’ve read of a freakishly cold English summer when the jet stream went hard and went south, stirring up all kinds of storminess.

        Otherwise I might be calling you Anonio Pardo. (Or Antonio Marron?)

      • Mosomoso

        My best skiing days are behind me. Mind, a good test of a cold summer is whether snow survives on top of the Scottish mountains.

        I think the jet stream is a vastly underestimated source of good and bad weather. Whether it causes climate; i.e 30 years of a trend, or merely moves weather around on a short term basisI would like to see investigated

        tonyb

      • How many storms ‘missed due to lack of observations?’

        Yea, Tony, ‘The first boat we read of, floated on an ocean,
        that with Portuguese vengeance had whelmed a whole
        world without leaving so much as a widow. The same
        ocean rolls now; that same ocean destroyed the wrecked
        ships of last year. Yea foolish mortals, Noah’s flood is
        not yet subsided: two thirds of the fair world it yet covers.’

        Herman Melville, ‘Moby Dick.’ Ch LVIII.

      • Spanish Armada, moso?

      • Beth

        That is a great reference. I recently started writing an article on natural variability/temperature extremes and this part is relevant to observations (or lack of) and that we don’t know as much as we think we do..

        ” To understand if it is possible-or likely- for temperatures to be substantially greater than the accepted ‘norm’ – that is to be truly unprecedented in the accepted records CET or merely anecdotal it is useful to look at the analogy of waves.

        At one time it was thought giant ship wrecking waves were mythical as few people had been around to witness them in the vastness of the oceans.

        ‘Once dismissed as a nautical myth, freakish ocean waves that rise as tall as ten-storey apartment blocks have been accepted as a leading cause of large ship sinkings. Results from the European Space Agency’s ERS satellites helped establish the widespread existence of these ‘rogue’ waves and are now being used to study their origins.

        http://www.world-science.net/othernews/040721_wavefrm.htm

        the link continues;

        ‘Severe weather has sunk more than 200 super tankers and container ships exceeding 200 metres in length during the last two decades. Rogue waves are believed to be the major cause in many such cases.

        Mariners who survived similar encounters have had remarkable stories to tell. In February 1995 the cruiser liner Queen Elizabeth II met a 29-metre high rogue wave during a hurricane in the North Atlantic that Captain Ronald Warwick described as “a great wall of water… it looked as if we were going into the White Cliffs of Dover.

        And within the week between February and March 2001 two hardened tourist cruisers – the Bremen and the Caledonian Star – had their bridge windows smashed by 30-metre rogue waves in the South Atlantic, the former ship left drifting without navigation or propulsion for a period of two hours.”

        As with the ocean and giant waves, so any abnormal conditions on land-in this case high temperature extremes need to be verified by four separate criteria;

        firstly someone to observe them, Secondly for someone to take the trouble to record the event in a coherent fashion, thirdly that the record should be preserved and fourthly that the record is readily accessible.

        As earths population has increased – Global population was some 800 million in 1750 and 7 billion today
        http://www.geohive.com/earth/his_history1.aspx

        and measuring technology and methodology has become more reliable and widely used , the likelihood of some, if not all, modern day extremes being captured has increased and with the accessibility offered by the internet all four criteria can be readily met. So the possibility of noticing really big extremes that stretch our understanding of natural variability has substantially risen over the years.

        tonyb

      • And let’s not forget that “Divine Wind” of 1281.

        The Spanish Armada had 130 ships and 26,000 sailors and soldiers.

        Kublai Khan’s invasion fleet consisted of 4,400 ships and 140,000 soldiers. All gone.

        Curiously, a previous invasion attempt in 1274 also got wiped out, with maybe 13,000 drowned. Maybe a climate expert told the Khan that 1274 was one of those “one in a hundred year events” – so he felt safe to go again in the same century!

        You can get into trouble listening to climate experts, lemme tellya.

      • Tony, only heard recently of rogue waves, fergit where. ‘
        Guess if hit, not many witnesses survive ter tell the tale.
        …. Like yer say, much ter learn.

  7. The 2015 spike in the two Klotzbach charts is certainly alarming. Dr. Curry I would greatly appreciate a link to the basin-by-basin data. Does this spike exist across all basins or is it thanks to the maxima of all basins happening to coincide this year? One of the fundamental tenets of my lukewarmist religion is that global warming does not result in more frequent and more destructive tropical storms, thanks to the lowered temp difference between tropics and arctics. I got this from Dr James Hansen whose public pronouncements are more often wrong than right, but it suits my bias set to believe him on this occasion. My ego has taken a few knocks recently and having to admit to warmists that they were right re tropical storms could be a crushing blow.

    • Relax, Mike. Klotzback’s own prediction as of 5 Aug for Nth Atlantic tropical cyclones is for less than average.

      Note, Klotzback has no links on his blog post and he actually calls the post a blog, which tells us he’s not really into accuracy.

  8. Prof Curry might be helpful to identify some basics for those of us new to ‘hurricane climate science’. I got this from wikipedia FWIW. Be great to get any corrections:

    1 The actual scientific topic is tropical cyclones of which a hurricane is just one type alongside, tropical storms, typhoons, cyclonic storms and cyclones.

    2 Tropical cyclones are storm systems with low pressure centres i.e big wind and rain occuring over one of 6 ocean basins around the equator.

    3 They love warm moist air coming off the oceans around the equatorish:
    Northern Hemisphere: North Atlantic, NE Pacific, NW Pacific, North Indian,
    Southern Hemisphere: SW Indian, Southern Pacific & Australian region

    4 Tropical cyclones are rare in the Southern Atlantic, weirdly enough.

    5 Number of tropical cyclones for the planet each year is around 87 + or – 10.

    6 Pacific ocean has the most tropical cyclones (that’s north and south together) and within that ocean it’s the NW Pacific that most cops it. They get the super typhoons.

    7 In the Northern hemisphere, tropical cyclones are called tropical storms, hurricanes, typhoons or, in the Northern Indian Ocean only, cyclonic storms.

    8 In the Southern hemisphere tropical cyclones are just called tropical cyclones.

    9 The Beaufort scale sets out wind speeds and duration over 1 and 10 minute periods, lowest speed for tropical storms and moving up into Cat 5 hurricane, supertyphoon, sever tropical cyclonic storm and cat 5 severe cyclone.

    10 There’s another scale the Saffir-Simpson scale but it’s just for hurricanes in the NE Pacific and Northern Atlantic i.e US centric focus, not helpful globally.

    11 Of the annual average 87 odd tropical cyclones that form each year around the planet, 47 are hurricanes/typhoons and around 20 are intense tropical cyclones leaving around 20 as just tropical storms, the slowest of all.

    12 the tropical cyclone season runs July to Nov for North Atlantic, sameish for NE Pacific and all year round for the rest.

    13 “ACE” stands for “Accumulated Cyclone Energy” and it comes to us from NOAA, the guys who gave us ‘2014 hottest year ever’. It only ‘measures’ the ‘energy’ of NE Pacific and North Atlantic hurricanes tropical storms so it’s not even a global measure. I guess in the absence of frequency of tropical cyclones and the absence of major losses caused by them (see Pickle Jnr), I guess intensity and ‘energy’ is all the climate alarmists have to fall back on.

  9. Pingback: Hurricanes And Global Warming: 10 Years Post Katrina | The Global Warming Policy Forum (GWPF)

  10. Hi, Judy. Thanks for posting. Can you comment as to whether the category % studies above take into account the somewhat arbitrary definitions for each category? Particularly as wikipedia notes the definition of Category 4 was slightly expanded in 2012 (from a range of 131 mph – 155 mph, to a range of 130 mph – 156 mph). It seems to me that a study could more usefully use the actual measurements of wind speed (or other key attributes) rather than the categories those measurements are subsequently translated into. Can you give your thoughts on this? Thanks.

    • Ted, 1 mph is arguably in the noise given the observational uncertainties. This is why i think loose categories e.g. major (3+) vs minor, or cat45 are best, since you have fewer boundaries to be fuzzy.

      The best metric (in terms of both understanding and damage) is Integrated Kinetic Energy (IKE), which includes wind speed squared but also accounts for the horizontal extent of the storm. This gives a better measure of overall energy involved, and is a much better predictor of damage.

      Note, my company CFAN is the first to provide forecasts of TC size (horizontal extent).

  11. Pardon my ignorance, but the seeming paucity of Cat4-5 hurricanes would appear to me to make percentage changes in incidence to be pretty noisy.
    1 Cat4-5 in the Indian Ocean in the 1970-1989 reporting period with 13 in the 1990 to 2014 – with this region responsible for 25% of all TCs (but not necessarily Cat4-5), this doesn’t seem to be a tremendously deep set of data.

  12. I too have an interest in Cyclones that dates from 14 months on Guam with the 54th Weather Recon Squadron in 1958-59. I maintained the navigation, radar, and weather equipment. At that time they flew B50s, a slightly more powerful version of the B29. The Pacific is an awfully big ocean. Recon tracks that were triangles of 1800 miles on each side can miss a lot of activity. (The rear bomb bay carried a large fuel tank, giving them a 6000 mile range.)
    Cyclones are one of natures large scale random and rare events, compared to other things. They are noise. As such, we are trying to tease out patterns from something that has no discernible pattern. There may be a long term pattern, but it is likely centuries long, not decades.

  13. Money would be better spent forecasting path and intensity of TC’s/Hurricanes than grinding on crap to look for man’s culpability in making things worse. Most damage is done by storm surge which is related to more than just intensity.

  14. Thanks, Judy. Nice discussion.

  15. This graph

    was constructed in 2012 (with update in2013 then abandoned). It was briefly discussed with Dr. Curry at the time. Physical mechanism for the correlation of the variables is not clear. If time delay between events is not just a nature’s coincidence, it is likely due to the up-welling of the conveyor current off the West Africa.

  16. Pingback: The Weather in 2014: Extreme Hysteria but Not Extreme Weather | thePOOG

  17. 2 comments:

    1. Much is made (and rightly so) of the loss of aircraft recon data in the Westpac. However, it should also be noted that the quality of TC intensity data in the Atlantic should have *significantly* improved after 1990. That was the point when the USAF aircraft transitioned to computerized high-density data. Having flown during that period (and having done some of the acceptance flights), I am quite sure that there was a huge improvement in the quality of max wind data.

    2. While the Dvorak technique is an important part of best track intensity in the ATCRs, it is not the entire story. I am aware of several important instances where a Dvorak analysis was disregarded when constructing the best track. Whether this is common or not is not clear and, not being a sat analyst, it’s difficult for me to referee between competing analyses. But, I think that it is quite likely that the primary authors of any particular ATCR probably skewed the data one way or another. Having seen the sausage being made, I would be very careful in making any proclamations based on small signals in that data.

  18. As it becomes more widely recognized that carbon dioxide has no effect on climate (proven at http://agwunveiled.blogspot.com which also identifies what causes climate change with R^2 greater than 0.97 since before 1900) it becomes apparent that human activity has no significant effect on hurricanes.

  19. Phil Klotzbach just tweeted:

    15 Cat. 4-5 TCs have formed in the N. Hemis. thru 8/31. This shatters the old record of 9 Cat. 4-5 TCs set in 2002.

    • David Wojick

      This clearly shows that the “record” is far too short to reflect natural variability. Given this much variance we probably need at least an accurate 100 year record in order to know what is going on.

      • Willard

        Please refer to my reply here;

        https://judithcurry.com/2015/08/30/hurricanes-and-global-warming-10-years-post-katrina/#comment-728827

        I agree that we would all be better off if we used much vaguer scales when dealing with historic reconstructions rather than tenths of a degree. I repeatedly state that and point out we can not expect fractional accuracy

        Perhaps you ought to be addressing your comments to those that don’t admit to the uncertainties and insist on claiming high accuracy rather than a tendency, such as GISS, BEST and the Met office, the latter of which maintains instrumental CET from 1659.

        Their figures represent the vast majority of the graphic you reference. You are surely not suggesting that I should switch from their scales to an entirely different set from 1538 to 1659? That would render the simple ‘man of 70 graphic’ somewhat meaningless.. When I create the other graphic I put the figures into much broader bands.

        tonyb

  20. Right on cue, here’s an extreme event in the North Atlantic!

    http://econnexus.org/hurricane-fred-threatens-cape-verde-islands/

    Hurricane Fred is the easternmost tropical hurricane ever in the North Atlantic. (Unless someone spots an error in my due diligence!)

    • Jim

      No it’s not. The data says another hurricane was in that area in 1892 . If the records were longer I am sure others would come to light.

      Tonyb

      • Did you bother to read my article Tony? Or at least look at the pictures?

        The 1892 hurricane (if NOAA’s historical records are to be believed) reached that strength west of where Fred did likewise this morning.

      • Jim

        Don’t be surprised if I am the only person to read the article if you take that tone.

        It said ‘in that area.’ such storms aren’t always going to form in exactly the same place and the historic records are woefully short and woefully inaccurate from which to draw meaningful conclusions.

        The amount of ships/people that were around to take observations In that area were tiny in previous eras, the data may not have been recorded or may have been lost.

        So, while interesting, it is of no great significance unless it could be matched against much older reliable records.

        Tonyb

      • Blimey. I go to bed and look what happens!

        As Eddie’s image makes clear, that’s the area where “easternmost” North Atlantic tropical cyclones form. As you say, it’s interesting. It’s also interesting (to me at least) that Ana became a fairly westerly tropical storm on May 9th this year:

        http://econnexus.org/early-start-to-2015-atlantic-hurricane-season/

      • Right on cue, someone is trying to imply modern climate exceptionalism from Fred. It’s the most outlandish claim since yesterday – ever! It’s been unprecedented since the last precedent!

      • Steven Mosher

        “The amount of ships/people that were around to take observations In that area were tiny in previous eras, the data may not have been recorded or may have been lost.

        Unicorns.. there might be unicorns!! cant rule out unicorns!!!
        even today data goes missing or lost.. everywhere we cant look there might be unicorns!!

        That said, focusing on extreme weather is pretty much a silly exercise for both sides.

      • “Focusing on extreme weather is pretty much a silly exercise for both sides.”

        Dame Julia Slingo of the once Great British Met Office would seem to disagree with you Steven?

        http://econnexus.org/climate-change-the-latest-evidence-and-implications/

        “The other thing that comes through time and time again in the discussions is that it’s not about the global mean temperature any more, that we need to shape the climate change message much more about ‘what does it mean for me, regionally and locally’, and that’s really around extreme or high impact weather”

      • So, what precisely do you disagree with in that quote of mine you excerpted?

        That there were fewer observers? That data might not be recorded? That data might be lost in the intervening years?

        Tonyb

      • That said, focusing on extreme weather is pretty much a silly exercise for both sides.

        You do provide a lot in just one little sentence.

        1. If ‘climate change’ doesn’t change the extreme weather, ( just the boring weather ), then it’s less likely to have significant adverse effects.

        2. The IPCC sets the focus on ‘extreme events’.

        3. The hurricane intensity issue is what led Landsea to quit the IPCC in protest over exaggerated claims. He didn’t choose the controversy, the IPCC chose it for him.

        4. There’s good reason ( Manabe early papers and this gem from Hansen ) to believe that extratropical storm intensity might decrease, not increase with global warming:

        5. The truth will mostly likely be found by those who either don’t choose a side or who have successfully divorced themselves from a side.

      • climatereason: So, what precisely do you disagree with in that quote of mine you excerpted?

        Had he meant anything precisely, he’d not have used the unicorn metaphor. In other contexts, “unicorns” have referred to evapotranspiration and solar activities.

      • Steven Mosher

        tony I am referring to a pattern of thinking.
        it goes without saying that whenever certain minds are faced with evidence, they have the same reaction. They point away from the evidence presented to what is not present. like clockwork.

        but when they present their own evidence they forget this tactic

      • Tonyb

        Speaking of oddities and “records-ever”, do you have any recollection of Faith in 1966? It was the “most” easterly hurricane “ever”, still a Cat 1 after it had done the big Atlantic circuit and ended up north of the UK, just 3 degrees off the Greenwich line. It was a wet year, obviously, with the Aberfan disaster, but they say there was a real drenching in August from Hurricane Faith, on top of other drenching.

        Or were you a busily drinking student at the time?

        (Btw, here in the world’s leading hemisphere, Cyclone Alby in 1978 got right to the southern tip of WA before losing hurricane status. That’s the most southerly I know of. But who used to hang around down there to measure cyclones?)

      • > So, what precisely do you disagree with in that quote of mine you excerpted?

        Arguing from ignorance is easy, TonyB. If you don’t like unicorns, think Tree Lobsters, whom you can’t prove they don’t exist. You might like this latest one:

        Source: http://www.treelobsters.com/2015/08/710-flap-jaq.html

        Any resemblance with real bloggers may only only be &c.

      • I promise not to use the argument from ignorance except in cases where people are in ignorance.

        Btw, for a freaky hurricane direction, what about the San Diego Hurricane of 1858? Certainly no big deal, but something tells me if it happened now…you-know-who would say it’s a big deal because of you-know-what.

      • Willard seems to believe that tree lobsters have a strong resemblance to tree crabs but I enjoyed the dialogue!

      • Stephen Mosher: They point away from the evidence presented to what is not present.

        Given the evidence that we have (as in Turbulent Eddie’s nice graph), what is the conditional probability that there were not other equally strong hurricanes in that area? In the last 150 years, say? In the 300 years including the peak of the Medieval Warm Period? You regularly defend counter-intuitive conditional expectations, how about conditional distributions? An answer can’t be computed without an explicit prior, but would you restrict attention to priors that have probability 0 for that area?

        Would you insist that the conditional probabilities of conjectured but unobserved events must always be treated as “unicorns”? Or are they not, as I claim these are, sometimes perfectly reasonable?

      • That’s not a tree lobster, it’s a bush crab.

      • The reason to refer to the past is strong and critical. We are talking about climate, not hemlines or weekend footy scores. The very people who invite us to keep a focus on recent events and findings are themselves all too willing to invoke the past constantly, but only as a vague field of reference to serve their conclusions and dogmas.

        In other words, comparatives are encouraged, all sorts of things are worse, hotter, drier, more extreme – but points of comparison are banned. There is no “than”. It’s all just “more”.

        Look at the comment that started this. The present Hurricane Fred is a rare event. It reached hurricane force at 22.5 W, whereas a hurricane in 1892 reached force at 24.1W. So Fred was indeed born a bit further east than Hurricane 5 of 1892, and both events, so close to the African coast, are very rare. So far, a good point, which proves nothing, but is well worth making.

        However it was not Hurricane 5 of 1892 which was born furthest to the east before Fred broke its “record”. It was Hurricane 3 of 1890, further south of Verde, which became a hurricane at 23.0W, just half a degree west of Fred.

        Now look at the tone of the comment, how Fred has come “right on cue”. Instead of being the most easterly known in the post 1851 record, it’s most easterly “ever”. What is the “cue” supposed to be and how hard is it to specify about “records”? After 115 years an observation for hurricane longitude was at last exceeded by half a degree and that is a big deal? Was 23.0W supposed to be some kind of unbreachable boundary? A Trump fence erected by sinister skeps…till Fred showed ’em!

        Not by baby talk and stunts can I be persuaded. Ever.

      • Sorry, I meant Hurricane 3 of 1900, not 1890. I got the 115 years right!

        Something else to give things more of an adult tilt. In discussions of the previous Hurricane Fred of 2009 (same name in same Verde region, for some reason), noted for being so strong so far south and east, the NHC observed:
        “THIS TYPE OF SYSTEM… HOWEVER…WOULD HAVE BEEN VERY DIFFICULT TO ACCURATELY OBSERVE BEFORE SATELLITE PICTURES BEGAN IN THE 1960S.”

        Their capitals – but worth capitalising.

      • Willard

        I won’t pretend that I understand your lobster metaphor. Squirrels, Unicorns and now lobsters.

        There was I thinking that it was perfectly logical to comment on the likely lack of observations in past eras due to the likely lack of observers- or that events might not be recorded or stored. As Mosh says, new data is coming along all the time which changes our perceptions of the past, so at some point more observational data might or might not come to the fore.

        As for the importance of extremes, There are whole Depts (The Met Office) and papers that concern themselves with them, quite apart from politicians worrying about them, that someone somewhere must think they are of some relevance.

        tonyb

      • mosomoso

        I don’t specifically recall ‘faith’ but I do vividly remember Aberfan as many of my relatives come from the Welsh coal mining valleys.

        I do remember this in 1986;

        ‘On 25 to 26 August 1986 the remnants of Hurricane Charley brought strong winds and heavy rain, with some flooding and damage to boats in west Wales.’

        We were camping at the time in a farmers field in North Wales and heard the forecast so secured everything down and sat it out for two days occasionally tying more ropes from tent to car and digging ditches inside the tent to drain water away.

        We emerged after two turbulent days and nights to pay the farmer who looked at us astonished as he thought everyone had evacuated.

        tonyb

      • Jim Hunt

        Mosh has a blind spot on historical events. Looking at extreme events of the past is essential planning to cope with what might happen in the future

        “‘The construction of regionally specific climatic histories and historical extreme weather events, and investigations of the memories of and responses to these events, must form a crucial component of any research that seeks to understand the nature of events that might take place in the future. These histories are also important if we are to be able to assess how different communities in different contexts might be affected by, comprehend and respond to future events. The purpose of the proposed project, therefore, is to examine the nature, timing and socio-economic and cultural consequences of, and responses to, climatic extremes in the UK. This will be achieved through a series of case study-based investigations across the UK and will cover an extended period between 1700 and the present. This study will employ a combination of archival investigation and oral history approaches in order to construct episodes of extreme weather and to explore whether and how these events affected the lives of local people and became inscribed into the cultural fabric and social memory of selected local communities within the case study regions. We will also explore how the recording of these events has changed overtime and is still changing.

        http://gtr.rcuk.ac.uk/project/CC66F416-E9CA-4D3A-95B9-748267ADCDC9

        Are we near neighbours? I was at the Met Office/Exeter Uni event last year as well. I thought the panel were pretty pedestrian with poor presentation skills and some terrible graphics (although I don’t doubt their knowledge)

        However, I thought Catherine Mitchell was pretty good and feisty and obviously hit the right note with the student audience particularly.

        tonyb

      • We’ve had this conversation before Tony! We are indeed near neighbours. As a “silver” surfer I take great interest in tracking hurricanes across the North Atlantic.

        Before moving to the West Country I used to live just west of Cardiff. My guitar teacher attended Pantglas Junior School at the time it became buried:

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

      • > [I]t was perfectly logical to comment on the likely lack of observations in past eras due to the likely lack of observers- or that events might not be recorded or stored.

        That’s a tad weaker than your claim that Jim’s data isof no great significance unless it could be matched against much older reliable records. It’s also weaker than your counterfactual If the records were longer I am sure others would come to light. Here’s the claim to which Moshpit responded.

        The amount of ships/people that were around to take observations In that area were tiny in previous eras, the data may not have been recorded or may have been lost.

        Claiming that we lack evidence is one thing. Arguing that only if we had this evidence would what we have be of any significance is quite another thing. Contemplating counterfactuals on this lack of evidence puts all this to yet another level. More generally:

        (1) Data D is significant iff we have evidence E.

        (2) If we had E we’d see P, which contradicts what J said about D.

        (3) But we can’t know E since nobody were there.

        If that’s not appealing to ignorance, I don’t know what could be.

      • Willard

        As you don’t appear to know the difference between tree lobsters and crabs I am not sure we should think you are the font of all knowledge :)

        I saw a tree crab in my garden just a few weeks ago.

        Admittedly it was only there as the seagull that had been carrying it missed the concrete path which he hoped would smash the crab and provide it with a tasty meal and it instead landed up in the tree.

        tonyb.

      • If you don’t get that the **Tree Lobsters** is a name of the series, that it refers to characters that are not drawn on this specific strip (hint: there’s a phylactery for a voice off), that one of their taglines for the series is “You Can’t Prove They Don’t Exist” (click on a few, you’ll see), then no wonder you don’t get Moshpit’s remark, TonyB.

        Since most of your work is dedicated to a JAQ based on an conspicuous appeal to ignorance, I guess the best you got is to try to humor me.

        Please, do continue.

      • Thank you Willard.

      • Steven Mosher,

        “Focusing on extreme weather is pretty much a silly exercise for both sides.”

        For agrument’s sake, I’d agree. We can’t change weather in a policy relevent way through GHGs from fossil fuel burning. But ultimately, this is what we want to figure out, it’s just unlikely that we’ll have consistent data over a meaninglul timeframe during our lives, if ever. But this also highlights how f’ing stupid the GHG emissions policy aspect of climate change politics is. The changes and time-scales involved make sense to study and adapt to over time, but don’t make sense for near-term decisions (probably less century out). Like you say, we don’t even prepare for the weather of the past. Priorities.

      • “It’s a stick insect, a critter that masquerades as a piece of wood, and the Lord Howe Island version was so large — as big as a human hand — that the Europeans labeled it a “tree lobster” because of its size and hard, lobsterlike exoskeleton.”

        http://www.npr.org/sections/krulwich/2012/02/24/147367644/six-legged-giant-finds-secret-hideaway-hides-for-80-years

      • willard: Claiming that we lack evidence is one thing. Arguing that only if we had this evidence would what we have be of any significance is quite another thing.

        Do you ever even try to write accurately?

      • richardswarthout

        Tony

        The discussion of missing evidence reminds me of Sherlock Holmes; his skill of detecting missing evidence and thereby solving crimes was not based on myth.

        Richard

      • What’s your beef, MattStat, and where is it?

      • Steven Mosher: “Focusing on extreme weather is pretty much a silly exercise for both sides.”

        Why? It’s the extremes that cause the most damage.

        Note, it is not an exclusive focus forever. But extremes deserve focused attention from time to time, such as now.

      • I love that Tony doesn’t get that CET is only one ship.
        You will note that he never appeals to what might otherwise have been observed back in 1600 had rss or uah been around.

        He justifies this by saying that during the modern Era CET is correlated with the global field, but never mentions – ala Feynman integrity – that we have no evidence that this correlation exists in prior periods. That is, in periods where we can’t measure the correlation, in periods where CET is the only record.

        When it comes to hurricanes his emphasis is all about the small number of ships and what they might have missed. When it comes to SST the emphasis is all about the small number of ships and changing methods of observation. It’s all too sketchy for him
        When it comes to CET it’s flipped. It’s never about the fact that CET is “one ship” and when it comes to other documentary evidence it’s never about the lack of precision in the methods. The monk wrote it was very cold. Ya let’s call that – 3c.

        All folks have to do is compare the tactics of Tony defending his CET work where he tries to extract everything we can know from the bits and pieces, to the tactics of Tony attacking other people’s work who are trying to do the same thing with hurricanes or SST.

        His bits and pieces come together so he can tell a story. Forget what’s possibly missing. Other folks are not allowed to stitch their pieces together because maybe unicorns.

      • Willard

        Why on earth would I have heard of an obscure internet based American comic called tree lobsters?
        tonyb

      • Mosh

        You are famously inconsistent. Was it you who said this?

        ————— ——- ———
        Steven Mosher | August 14, 2013 at 11:41 am |
        GaryM

        I should have said two GOOD arguments, yours are stupid

        “GaryM | August 14, 2013 at 12:02 am |
        Steven Mosher,

        There are more than two arguments about the “reliability of the record.”

        “There is the lack of coverage,

        This is false. the spatial coherence of the temperature field is such that one can reliably estimate the entire field from very few stations. At the extreme you can take one reliable station ( CET) and estimate the whole globe. lower spatial coverages don’t impact the reliablility, the impact the uncertainty. One simple way to look at this is by sub sampling. We start with 39000 stations to compute the field. randomly select 100 stations from that field and you will get the same answer.

        https://judithcurry.com/2013/08/13/impact-of-climate-population-and-co2-on-water-resources/#comment-364794

        Steven Mosher | October 4, 2013 at 12:13 am |
        “Odd the way your crappy BEST moving average is so far outside the data in 1780. ”

        Another idiot comment from greg.

        The BEST Data at 1780 is the average of the entire field. the small patch of england tony refers to as well as most of europe and some of north america.

        Tony is comparing CET ( a few square miles) to a much larger area.

        That location (CET) along with a few others has reasonable correlation with the entire globe, although with CET ( and others) you will find years in which it is at odds with the rest of the world.

        In other words, the thing you point out is expected and not anything odd.

        —– ——

        I think it is useful to try to determine the approximate Historic temperature of CET as there has been reasonable correlation in the past as you-and many climate scientist-confirm. Perfect? No. Useful? Yes.

        Gary M’s list of things you have been inconsistent on is listed in that thread as was my jocular comment to Judith to witness what you said.
        tonyb

      • > Why on earth would I have heard of an obscure internet based American comic called tree lobsters?

        Because you would have clicked on the link before trying to mock it.

        Do you have other loaded questions like that instead of acknowledging what I’m here for in the first place, i.e. your appeal to ignorance?

      • Not inconsistent Tony. You need to read harder. Stating what we know,
        estimating what we dont know, and citing uncertainties and assumptions, is what I suggest.

        Lets take CET. you only state what you know. You dont estimate what you dont know, you hand wave. you dont cite or calculate uncertainties, and you dont highlight assumptions.

        Lets take Hurricans: you denegrate what we know, you criticize those who estimate what they dont know, and your focus is all on the uncertainties and assumptions.

        Same for SST

        The reason for this divergence of approaches is simple. you have more invested in CET.

        Feyman integrity..

      • Willard

        No, I didn’t see the link until you just referred to it. The lobsters appear in my browser as a large four panel cartoon. The link is barely visible at the bottom.

        Perhaps you see something different?

        tonyb

      • Mosh said

        “Not inconsistent Tony. You need to read harder. Stating what we know,
        estimating what we dont know, and citing uncertainties and assumptions, is what I suggest.”

        its clear what you said twice. I don’t need to read harder, you need to be either consistent with your comments or write more clearly in the first place.

        tonybi

      • > Perhaps you see something different?

        Yes, I do. Read back my first comment. Report.

      • Tony you are simply not getting that you adopt two different behaviors.

        Lets see if I can help

        “This is false. the spatial coherence of the temperature field is such that one can reliably estimate the entire field from very few stations. At the extreme you can take one reliable station ( CET) and estimate the whole globe. lower spatial coverages don’t impact the reliablility, the impact the uncertainty. ”

        This is for Land. the issue is Uncertainty. You can reliably estimate the globe from very little data. BUT the uncertainty is large, AND you are making one assumption: That the correlation in say 1750 or 1600, or 1500… is the same as in the modern record

        now

        “This is false. the spatial coherence of the temperature field is such that one can reliably estimate the entire field from very few Ships At the extreme you can take one reliable ship and estimate the whole globe. lower spatial coverages don’t impact the reliablility, the impact the uncertainty. ”

        However, while you would except the first argument— we can use CET as a way of understanding the past –albeit with uncertainty,
        your attitude toward SST, is ( IMHO) that data prior to 1950 is totally unusable. in short worthless.

        basically, when there is SPARSE data that you SPECIALIZE IN
        a) CET
        b) Old newspaper articles about Arctic ICE

        there is SCANT attention to what is missing. There is scant attention to the uncertainty side of the ledger and more attention to the knowledge side of the ledger.

        Where there is sparse data that you DONT specialize in
        a. SST
        b. Hurricanes
        There scant attention to what is known, and all the attention is paid to
        what might be missing, what might be wrong, etc etc.

        My position is pretty much the same. You have to pay attention to both the known and the uncertain. When a commenter says Nothing can be known…. of course I point out the ways scant evidence can be used to constrain the unknown
        When a commenter pretends that scant evidence has no uncertainty I am going to remind him of the flaws and assumptions in his scant evidence.

        Simple question tony

        1. Can we learn anything useful from SST measures prior to 1950.
        2. Are those documents as important as any monk writing about sunny days.
        3. Can wwe learn anything useful from early ship reports of hurricanes

        or is everything you havent studied in detail easily dismissed as junk.

      • Steven Mosher: Tony you are simply not getting that you adopt two different behaviors.

        I think you are wrong about that. If you quote what he actually has written and the claims, assertions, propositions that he was responding to, I think you’ll find that he consistently argues against extreme or absolutist claims.

      • richardswarthout

        Mosher

        Tony uses vast resources beyond CET and the writings of a monk. You appear to ignore, or may not have read, the works of Dr Brown and Dr Lamb. Are you aware of his trips to the Alps, his research of ice cores, and his deep knowledge of ship architecture, navigation, and operation. And always describing the limits of his evidence. I also suspect, based on his diligence and energy, exposed by his works, that he knows much detail about agriculture over the period 900-1900.

        Richard

      • > If you quote what he actually has written and the claims, assertions, propositions that he was responding to, I think you’ll find that he consistently argues against extreme or absolutist claims.

        Then it would be easy to show. Go for it. Fast is fine, but accuracy is everything.

      • Mosher must be bored with juggling the temp data. He has stooped to spending significant time and effort to nitpick TonyB. There are far more deserving targets, Steven. Hockeypuck is running loose all over the place. What say you, willy willy? You seem to have become Mosher’s head cheerleader? Things slow over on kenny’s lonely blog?

      • I’m here for the Tree Lobsters, Don Don. Try to prove they don’t exist.

        Denizens already know that TonyB oftentimes seals himself in JAQs.

      • Tony uses vast resources beyond CET and the writings of a monk. You appear to ignore, or may not have read, the works of Dr Brown and Dr Lamb. Are you aware of his trips to the Alps, his research of ice cores, and his deep knowledge of ship architecture, navigation, and operation. And always describing the limits of his evidence. I
        #################

        1. I’ve read tonys material.
        2. There is no description of methods
        3. No description of quantified uncertainty.
        4. Lots of stories.

        Until someone can read the original sources and reproduce his results you have one man’s word.

      • Mosh

        Read harder, as someone keeps entreating us.

        I have told you at least four times that the methodology I use is the same as van engelen et al. I know you saw one of my replies at least as you referred to it but still you make your unfounded claim.

        Any ‘anecdotal’ quotes are always referenced to the original so they are not stories. Anyone can read them as they are generally in public places such as the met office library or the Scott polar institute in Cambridge. They are also often cross referenced to other historical references or scientific papers.

        I do state the uncertainty. Again I have told you this. It is at least half a degree c which becomes more unquantifiable the further back in time I step. At this stage, again as you know, I try to put likely temperatures within a broad band. I adhere to Lambs maxim that ‘ you can understand the (temperature) tendency, but not the precision. ‘

        How are you doing with quantifying your anecdotal raw temperature data? Or are figures inherently superior to text?

        Tonyb

      • > [T]hey are not stories.

        It might be best to call them accounts, or more precisely chronicles:

        Are the data valid as being reasonably representative of CET and the wider UK climate over the years? Allowing for exaggeration and short memories by chroniclers, some 15 accounts of the changing climate and other references (see sections 3.5 and 3.10) seem to reinforce what our eyes are telling us.

        https://judithcurry.com/2015/02/19/the-intermittent-little-ice-age/

      • Willard

        Yes, I like the word chronicles, rather than accounts or stories.

        As you show in your link, early on i make no claim that the chronicles can demonstrate accuracy to tenths of a degree but can give us a good steer on the direction of travel of temperatures.

        Tonyb

      • > [E]arly on i make no claim that the chronicles can demonstrate accuracy to tenths of a degree but can give us a good steer on the direction of travel of temperatures.

        The “reinforce what our eyes are telling us” in what I just quoted goes a bit beyond that, TonyB. Also, the “formula” you “devised” to “note the real world impact of the changing climate on a person aged 70 years old” goes even beyond that:

        As you can see, this chart goes into the tenths of degrees. This seems to contradict that you “make no claim that the chronicles can demonstrate accuracy to tenths of a degree.”

        Please advise.

      • Willard

        The chart you show demonstrates the tendency very well. That is the intention.

        I can do no more than repeatedly stress that historic reconstructions can not be highly accurate. When you slice and dice a figure you end up with small amounts and that is why it is important to point out that it can’t be accurate to those small amounts.

        I look forward to mosh, CRU giss et al confirming they do not have accuracy to tiny amounts but their reconstructions merely show the tendency.

        Tonyb

      • tony

        you cannot make a claim about “tendency” or slope without
        before making a claim about individual values.

        For example.

        If 1500- 1550 Is “somewhere” between 10C and 15C
        And
        1550 -1600 is somewhere between 11C and 15C

        If you ploted the two centers of of those would give an impression
        of “tendency”.. But How much tendency and how certain we are of the tendency relies on DOING MATH.. using your pencil, NOT yiour eye balls.

        Again, last time you used your intuition to ‘classify’ temperatures I showed you a mathematical way of doing it. A way that is defenseable,

      • The scale for your chart the real world impact of the changing climate on a person aged 70 years old you created using a formula you devised is in tenths of degrees, TonyB. This seems to contradict that you make no claim that the chronicles can demonstrate accuracy to tenths of a degree.

        Please address this.

      • > Please refer to my comment here […]

        In that comment, there is the claim that

        It is at least half a degree c which becomes more unquantifiable the further back in time I step.

        Yet, the chart named Average Temperature Experienced During Lifetime of Someone Born at the Start of a Decade and Who Died in the Last Year of a Decade 70 Years Later varies by tenths of degrees each year, starting in 1540 and ending in 1960.

        Just imagine if the IPCC did this, TonyB.

      • TonyB,

        Thank you for this misplaced comment:

        https://judithcurry.com/2015/08/30/hurricanes-and-global-warming-10-years-post-katrina/#comment-728851

        You say:

        I agree that we would all be better off if we used much vaguer scales when dealing with historic reconstructions rather than tenths of a degree. I repeatedly state that and point out we can not expect fractional accuracy

        I don’t know where in that text you say that you would have been better off using a vaguer scale. What I do know is that your claim that you make no claim that the chronicles can demonstrate accuracy to tenths of a degree. You should retract that claim, since it’s clear that the chart named Average Temperature Experienced During Lifetime of Someone Born at the Start of a Decade and Who Died in the Last Year of a Decade 70 Years Later varies by tenths of degrees each year, starting in 1540 and ending in 1960.

        Will you amend the posts where you published this chart and edit the chart to reflect that you would have been better off using a vaguer scale?

        Until then, it would be great if you could retract your claim that you make no claim that the chronicles can demonstrate accuracy to tenths of a degree, because it’s quite obvious that you did.

        ***

        I have two questions regarding this.

        Perhaps you ought to be addressing your comments to those that don’t admit to the uncertainties and insist on claiming high accuracy rather than a tendency.

        First, if you could point to me any commitment from my part regarding these squirrels, that would be great too. Failure to do so will demonstrate that you’re just deflecting.

        Second, I’m not sure how you “admit to the uncertainties” at all, or for that matter what you mean by that. What’s clear from your chart named Average Temperature Experienced During Lifetime of Someone Born at the Start of a Decade and Who Died in the Last Year of a Decade 70 Years Later is that you assign tenths of Celcius to chronicles. While I can understand the uncertainty bars for tenths of Celcius, I’m not sure where are the error bars for your chronicles.

        So my (main) question is: please explain chronicle uncertainty.

        Many thanks!

      • Willard

        I can’t tell you how (genuinely) flattered I am by your close attention to my modest works and in particular your comparison (however unfavourably) with my works to the IPCC. Just think how great a temperature reconstruction could be created if I had just one millionth of the resources they do. Perhaps you would put in a word for me with the powers that be, as a truly reliable historic temperature reconstruction for the past 1000 years would be a prize worth gaining.

        Now, it seems necessary to reiterate that the man of 70 graphic (which is obviously less trivial and unimportant than I had believed it to be) would be pointless and incomprehensible if it tried to mix two very different scales, one to half a degree of accuracy and one –CET used by the Met office- to tenths of a degree. My 120 year long reconstruction is a fraction of the Met Offices much longer one so I need to use their scale but, as you must have noticed in paying such diligent attention to my work, I go out of my way on numerous occasions to point out the flaws and inherent inaccuracies of historic temperature reconstructions. The purpose of the original reconstruction is given below, followed by some of the cautionary caveats;

        Start of paper * A warming trend can be observed from 1659, the start date of Central England Temperature (CET)- the oldest instrumental record in the world- to today. It would be a notable coincidence if the warming started at the exact point that this record began. The purpose of this paper is to reconstruct CET from its current start point, through the use of diverse historical records, to 1538, in order to see if the commencement of this centuries long warming trend can be identified from within this time frame.

        (conclusion) The period from the start of the ‘Bruegel’ winters from around 1564 to around 1620 appears to be probably the second coldest extended period in the record-but somewhat behind the decades commencing 1670. The notable warm bump around 1630 to around 1670 confirm the upwards trend we could note at the very start of the instrumental record in 1659, as shown in Figure 1, as the cold winters of that period were again ameliorated by some notably warm summers. This warm bump seems to be of equal value to the one around 1730 that Lamb observed, and like that period warrants further investigation in a future paper. It appears therefore that the instrumental record did capture the coldest period of the LIA.

        Caveats

        * Considerable uncertainties abound in virtually every area of historic temperature reconstruction-including this one- and the ‘error’ bars are very broad. In the case of ‘1538’ plus or minus half a degree Centigrade.

        *Any attempt to construct a single global or even Northern Hemisphere temperature covering many centuries will encounter substantial difficulties, as incomplete information from novel proxies will probably not adequately represent the extremes that are experienced at either end of the temperature spectrum, so what is considered the ‘average’ is possibly representative of no climate state that actually ever existed.

        * The 1538 reconstruction will be updated as further evidence becomes available. In particular we need to assess the subjectivity of written records whereby one chroniclers ‘excessive heat’ may be someone else’s ‘pleasantly warm’.

        * To paraphrase Hubert Lamb we can know the (temperature) ‘tendency’ but not the ‘precision’ when we delve back in time. Uncertainty shrouds much of the past and in consequence perhaps we believe we know much more than we currently do.

        * The very pertinent comment is made that; “Inferences from regional data in isolation will clearly provide a biased view of larger-scale changes.”

        * The phrase ‘the greatest-drought/floods/snow/heat- in the memory of any man living’ occurs frequently, but we should not take this as literal (unless it was a claim made by a noted historian) but should instead consider the event mentioned is likely to be ‘exceptional’ for at least 20 years. Generally there is further information available against which such extravagant claims can be checked

        * We must be cautious in believing that any single instrumental record can act as a reliable proxy for the entire world as was observed here.

        * However, as we had earlier observed that instrumental records should not be considered accurate to tenths of a degree we are perhaps splitting hairs. Consequently, more accurately we should observe that the ‘direction of travel’ of temperatures, when combined and constrained by historic records, shows that at several points from 1538 there are similarities to the modern era as regards warm periods.

        * Tendency’ is a very good word and is preferable to ‘preciseness’ which has become an integral part of the climate science lexicon.

        with regards
        tonyb

  21. “We are all pencils in the hand of God.” ~Mother Teresa

  22. As the geo magnetic field and solar magnetic field continue to weaken going forward the result will be a colder climate.

  23. This will be evident before this decade ends . Hurricanes or lack of hurricanes neither here or there , as well as ENSO, which are examples of blips in the overall climatic picture governed by Geo /Solar Magnetic Field Strength ,Milankovitch Cycles ,Land /Ocean Arrangements all of which since the Holocene Optimum favor overall cooling and will continue to do so going forward.

  24. Coincidence that a strong El Nino is in progress while at the peak of the Pacific cyclone season this year and setting records?

    • Yes, shear coincidence.

    • yes El Nino spikes the pacific TCs (dampens atlantic TCs)

      • I agree exactly, El Nino strong Pacific Tropical activity weak Atlantic activity.

      • I certainly agree.

        However, it is unfortunate that we cannot really compare this year, as an example, to pre Satellite era years. Our pelagic observations were not exactly robust prior to that. When was the last time we had this instance in climate time with respect to a flipping AMO, current PDO and ENSO, solar cycle etc. to accurately compare? 1892?

    • Not just any El Nino either, but in absolute temperature terms it could be the warmest, so records should not be surprising.

      • The warmest in absolute temperature terms since what other date Jim?

        Would it be fair to compare measurements of ENSO events from the 1800’s?

      • Yeah I wonder why it might be the warmest? hmm I think it is foolish to think that we won’t see more extreme weather events being affected by the continued rise in temperature. I think If you accept that temperature can affect the weather then you have to accept that ever rising temperatures can affect the weather too.

      • ossqss, sure if you have managed to find reliable Pacific hurricane records from the 1800’s it would be a fair comparison, but until then, it is just a nonsense question.

      • I think it is foolish to think that we won’t see more extreme weather events being affected by the continued rise in temperature.

        I’ve just come back inside after an afternoon beer with my wife in the back yard.

        It’s late August and though not quite as hot as a month ago, still quite warm.

        I sat very still for my beer because not a single leaf on the trees was moving from the calm state of the atmosphere. This was the last dog day of summer.

        Crack an introductory meteorology textbook and you will find that weather is determined largely by the motion of the atmosphere, and the motion of the atmosphere is determined not by temperature but by the gradient of temperature.

      • Not just any El Nino either, but in absolute temperature terms it could be the warmest, so records should not be surprising.

        If temperature were the important factor, then the Atlantic would have a maximum during El Nino years also, but instead, the Atlantic incurs a minimum during El Ninos.

        Changes in shear can explain the pattern much better:

      • The temperature provides the energy, of course. More temperature, more moisture, more energy. It’s the fuel available for when it happens.

      • Jim D | August 31, 2015 at 9:06 pm |

        ossqss, sure if you have managed to find reliable Pacific hurricane records from the 1800’s it would be a fair comparison, but until then, it is just a nonsense question.

        —————————————-

        So, what records do we trust from the 1800’s and why? Is any terrestial dataset from that timeframe complete without human (anthropogenic) intervention? I mean, 1850 is a big baseline year for many researchers on many topics, no?

        Just curious.

        Sorry for clogging your blog Judith.

      • Jim D: The temperature provides the energy, of course.

        Quick revision needed. It is the sun that “provides” the energy. The temperature is a partial measure of how much energy there is (I call it partial because of the transfer of latent energy, which may not change temperature.)

      • The temperature provides the energy, of course. More temperature, more moisture, more energy.

        No. Thermal energy is what makes the little molecules of mercury bounce around in the thermometer, rising and lowering in volume in response.

        The kinetic energy which makes the parcels of atmosphere move, not just the little molecules bounce around in place, is forced by pressure gradients. Typically the pressure gradient is determined by temperature gradients. For the jet stream, those gradients are horizontal. For the thunderstorms which enable hurricanes, the vertical gradient comes from a potentially unstable parcel that stays warmer then the air at the heights to which it rises.

        If, hypothetically ( hypothetically, because orbits, shapes, sunshine, et. al. won’t let it happen ) temperatures were warmer but uniform over the earth, there would be no wind or storms.

        Hurricanes are multifactoral, but there are some things which might intensity hurricanes at the margins. CO2 RF might allow more cooling aloft and less near the surface which would destabilize the atmosphere somewhat. However, this would be small and in direct contrast to what the models predict, namely the ‘Hot Spot’ which should be a larger stabilizing factor for the tropics.

      • ossqss, I don’t know why you are so interested in the 1800’s. Please explain. How about the 1700’s, or 1300’s? It is today that we are seeing a rather strong El Nino and tropical storms may be about to match that, yes? This temperature is unprecedented in the period for which we have good records. This may also portend the future, which is also more relevant than your 1800’s, for which there is too little Pacific data to make any judgement of any kind.

      • If you want to dispute the hypothesis stated also by Webster et al. or Emanuel that sea-surface temperatures could be linked to hurricane intensities, go ahead. Correct them or defer. This hypothesis is fairly well known. I think it was Gray that identified 80 F as a critical temperature for hurricane formation to even be possible. It’s a very strong connection, identified now in decades of observations. You still want to argue with him? Larger warm areas can lead to longer tracks too, and the warm areas are especially large in a warmer world with an El Nino. By saying that there is a connection between warmer temperatures and stronger tropical storms, I don’t think I am saying anything that should be a surprise or hard to understand.

      • turbulent eddie: No. Thermal energy is what makes the little molecules of mercury bounce around in the thermometer, rising and lowering in volume in response.

        Yes. It is the energy that provides the temperature, not the temperature that provides the energy.

      • The way I look at is that the earth was only around 5C cooler during the last ice age and now we are talking about the probability of going over one third to two thirds of that temperature change in a little over 200 years. I think that would be a pretty dramatic change in such a short amount of time relative to most past fluctuations And we know how the temperature affected the earth;s climate by dropping only 5C.

      • Jim, and others who have posted replies….you have missed the important point. Energy by itself does not contribute to hurricane intensity. It is the energy differential, otherwise you would not have intense storms on colder planets, or in colder climates.

        It does not follow that a warming climate necessarily will result in increased cyclone activity or intensity. If a changing climate resulted in greater difference between energy accumulating at the tropics than at the poles, then it might do.

      • The way I look at is that the earth was only around 5C cooler during the last ice age and now we are talking about the probability of going over one third to two thirds of that temperature change in a little over 200 years. I think that would be a pretty dramatic change in such a short amount of time relative to most past fluctuations And we know how the temperature affected the earth;s climate by dropping only 5C.

        It’s more complicated than that.

        The ice ages occurred, not because of annual average temperature changes, but because of local, seasonal changes – cooler summers, but warmer winters. Now, the ice accumulation did have feedbacks, but the ice ages and the peak of the inter-glacial are not analogues of warming. In fact, the peak of the inter-glacial, known as the Holocene Climatic Optimum, paradoxically had colder winters, in the NH anyway, but longer, hotter summers. If you just think about global annual average temperature, you miss what happened and draw incorrect analogies.

      • If you want to dispute the hypothesis stated also by Webster et al. or Emanuel that sea-surface temperatures could be linked to hurricane intensities, go ahead. Correct them or defer.

        I believe they would agree with what I posted.

        It is not the temperature change of the sea surface alone, but rather, the temperature change of the sea surface in comparison with the temperature change of atmosphere above that will determine the conditional instability of the tropics. If more warming took place aloft than at the surface, stability would increase, not decrease. If more warming took place at the surface than aloft, stability would decrease. Now, MSU measurements, anyway, do indicate decreased stability ( more warming at lower levels than upper levels ) but models predict increased stability ( the Hot Spot ). Further, radiative models alone indicate a decrease of net radiance at the surface in the tropics with increased CO2:

        meaning less radiance into the tropical oceans.

        It’s quite a bit more complicated than that, of course, but in any event, the extent of effect would seem to be marginal ( because upper and lower tropical atmosphere are both warming ).

        I think it was Gray that identified 80 F as a critical temperature for hurricane formation to even be possible. It’s a very strong connection, identified now in decades of observations. You still want to argue with him?

        This is based on correlation, not causation.
        The same factor which cools ocean waters, namely colder drier air masses from the poles, is also what provides wind shear which disrupts or weakens tropical cyclones and implies a lack of low level convergence. This is particularly evident in the areas ( such as the Eastern South Pacific ) where no recorded tropical cyclone formation has taken place. The Andes mountains channel Antarctic air masses past the equator to the North. SSTs are indeed cooler in the Eastern Pacific, but because the Antarctic air masses have a direct path there’s little convergence in the region but lot’s of shear. So, again, the temperature only hypothesis may be misleading or at least incomplete.
        Here is a trajectory plot of the area:

      • Now, the ice accumulation did have feedbacks

        And warming has feedbacks and other consequences in terms of the water cycle, sea level, ice melt. I also think some research indicates that AGW could be changing ocean currents which could lead to further changes. I think you underestimate the significance and consequences of this potential rise in temperature. We still have over 1.2 of temperature rise to go before we reach the theoretical danger point. So what we see now is not really an indication of the consequences in the future.

      • Eddie, also there is some research that indicate that AGW might be changing the jet stream which has a significant impact on the weather. I have said it before. We are conducting a grand experiment on the earth to see what CO2 will do to our climate. And the “skeptics” seem a little to sure what the consequences will be negligible.

      • joseph

        I am very interested in the jet stream. Could you link to the article confirming AGW/jet stream correlation?

        Thanks

        tonyb

      • “Not just any El Nino either, but in absolute temperature terms it could be the warmest, so records should not be surprising.”

        Exactly, records shouldn’t be suprising.

        +1000

      • Eddie, also there is some research that indicate that AGW might be changing the jet stream which has a significant impact on the weather.

        But it might be making storms less intense and reducing temperature variability. Reduced temperature gradients and increased absolute humidity tend to support those ideas.

      • “We are conducting a grand experiment on the earth to see what CO2 will do to our climate.”

        CO2 is already part of the climate, so don’t you have your results already?

        Andrew

      • aaron | September 1, 2015 at 12:28 pm |
        “Not just any El Nino either, but in absolute temperature terms it could be the warmest, so records should not be surprising.”

        Exactly, records shouldn’t be suprising.

        +1000


        http://www.co2science.org/subject/m/summaries/mwprussia.php

        If 720 years ago we had been recording temperature for 100 years and had really good records for 30 years we would be hearing:
        1. “Warmest year EVAH.”
        2. The temperatures have increased xxx per decade and this is strange and unnatural and must be due to ASW (Anthropogenic Something Warming) perhaps due to the use of gunpower, fireplaces, animal husbandry, angering the gods, etc.
        3. “The Arctic is melting” – it will be all gone
        4. The Antarctic is melting”” and it will be all gone.
        5. “The glaciers are melting” (given that we are finding tree stumps where glacial retreats are happening and the siberian tree line was shifted hundreds of kilometers further north). In fact their glacial melting was provably much worse.
        6. “The sea is rising and we are going to drown!!! ” Given that the sea level was 6 inches higher – they actually had something to worry about..

        They would have taken a ruler to the temperature rise of the past decades and said “1400 is going to be 1°C to 3°C warmer than today”.

        They would have then prayed to the gods to find out what was causing ASW, a procedure about as effective as current climate science.

        And they would be just as wrong about 1400 as current climate science is about 2100.

        And the current decade is not the warmest and is at least 10°C below the warmest historic decade. We can’t even prove (since it is pretty obvious that it isn’t) that the 2010s are warmer than the MWP.

      • Tony, I don’t know about confirming it, but here is an article some that research.

        http://phys.org/news/2015-02-evidence-link-wavy-jet-stream.html

      • Joseph,

        “I think If you accept that temperature can affect the weather then you have to accept that ever rising temperatures can affect the weather too.”

        Reasonable enough. Now, is it a given that ever rising temperatures could in no way affect weather such that weather events become more uniform and less extreme?

      • Right, Andrew and it has gotten warmer and we will see what happens if we don’t slow down.

      • Tim, rising temperatures with ice melt, changes to the ocean, land and atmosphere is not a recipe for a stable climate.

      • Joseph, I think there’s lots of geological evidence that 1/3 of 5C/200yrs isn’t very extreme. The rate doesn’t seem outside natural variability and as PA shows, we aren’t near historical highs. It might be concerning if we has much more land ice near mid and low latitudes, as things are, nope. This warming looks like it will be a good thing.

      • Tim, rising temperatures with ice melt, changes to the ocean, land and atmosphere is not a recipe for a stable climate.

        Actually, in the seasonal variation, summers are less variable than winter, with less overall kinetic energy, even including hurricanes.

        This stands to reason as increased latent heat and reduced temperature gradients mean less imbalance, imablance which is only re-balanced by convective transport.

      • “Right, Andrew and it has gotten warmer”

        It gets warmer and colder all the time. So, is the C02 responsible for that?

        Andrew

      • Reduced temperature gradients and increased absolute humidity tend to support those ideas.

        You keep repeating this. So where is this research that finds that climate change will moderate extreme weather events?

      • Joseph,
        From THE source: “Whenever there is an extreme weather event, such as a flood or drought, people ask whether that event was caused by global warming. Unfortunately, there is no straightforward answer to this question. Weather is highly variable and extreme weather events have always happened.”
        So I think the answer (to this point in time) is ‘observation’…….to this question ” So where is this research that finds that climate change will moderate extreme weather events?”……..or to be more accurate since observation, so far, does not show an increase in extreme weather (yet?) then it’s equally plausible that it may moderate vs. increasing. After all, temps have been rising, correct?

        The quote goes further: “Detecting trends takes time, particularly when observational records are rare or even missing in certain regions . An increase in extreme weatheris expected with global warming because rising temperatures affect weather parameters in several ways. (My words…..no detail as to how they’ve changed). Changes in the frequency (My words……in some cases, IE hurricanes, decreased recently but not much of a net change historically) of extreme events coinciding with global warming have already been observed, and there is increasing evidence that some of these changes are caused by the impacts of human activities on the climate.”

        It’s interesting that in one paragraph it’s stated that weather is variable, but in another they’re relying on ‘coincidental’ evidence.

        http://www.skepticalscience.com/extreme-weather-global-warming.htm

      • or to be more accurate since observation, so far, does not show an increase in extreme weather (yet?) then it’s equally plausible that it may moderate vs. increasing. After all, temps have been rising, correct?

        I asked for the scientific research that indicates that climate change will lead to a moderation of extreme weather events, not your opinion, Danny.

      • Joseph,
        And I provided that source from the lords of climate…..SKS, Joseph.
        Or did ya miss the link, Joseph?

        If more extreme events aren’t occurring (observation?), then how would you describe it, Joseph?

        Sks indicates they ‘expect to see it’, but even they didn’t come out and say they do, Joseph.

      • Danny, we already have increased intensity heat waves and precipitation events in certain regions. It’s difficult to find trends because for some events the observations are not there or by definition “extreme” events are rare so there isn’t a large sample. This will only intensify as we get warmer.and the quality of the data should improve as we get more observations.

        What I am still looking for is science that finds that warming will moderate extreme weather events. I haven’t seen anything that indicates that climate change has done so or expected to do so because of other effects like this temperature gradient that TE has been going on about. I want to see actual citations to papers, ok?

      • Joseph,
        I agree that there are a reasonable number of indicators of increasing temps. and droughts. But when I look for alternative scenarios w/r/t tornadoes and tropical cyclones I find that up until about 2007 many published indicators were up (a couple of links follow), but since then it appears that storms (those particular indicators) seemed to have actually reduced (at least in frequency) here in the U.S. All this has happened coincidental with ‘the hiatus’ but while CO2 has increased. When looking, I find higher costs associated with damage, but that’s not an easily compared metric.

        This is why I used the term “observations”. This is not what the science has expected and even projected, but finding a paper?
        http://nrc.noaa.gov/sites/nrc/Documents/SoS%20Fact%20Sheets/SoS.Fact.Sheet.Tornadoes.and.Climate_FINALv2_May2013.pdf
        http://www.skepticalscience.com/hurricanes-global-warming.htm
        http://www.spc.noaa.gov/publications/mccarthy/tor30yrs.pdf

      • My point was about extreme weather in general whether or not AGW will have an impact on hurricanes or tropical storms is still being researched. I don’t think we have to be certain about hurricanes to understand the potential risks from extreme weather.

      • Joseph,
        Well it depends then on how you prefer to define ‘extreme weather’. I tried to answer with at least two of the more powerful systems which I’m aware of and the observable lack of increase (at least in frequency in the U.S.), so what else would you find of interest and I’ll try to research after work (at lunch)? It’s an interesting question and one that has given me pause when I’ve looked to see the associated frequencies especially when science explicitly was/is expecting a different result. That, and it’s association with the hiatus.
        (It’s an area of unsettled science IMO).

      • Andrew, do you think we will never find out whether the IPCC position is correct?

      • “Andrew, do you think we will never find out whether the IPCC position is correct?”

        You didn’t answer my question, and I don’t give a rat’s rear end about what the IPCC position is.

        Andrew

      • TE, as Emanuel has shown, for hurricanes the temperature differential that matters is between the sea-surface temperature and the storm outflow, and this gives an upper bound to hurricane intensity. Warming the SST raises this upper bound, and this makes sense because the latent heat available increases with the sea-surface temperature, and more energy leads to stronger winds. It is fairly clear that the strongest storms occur over warmer waters.

      • TE, as Emanuel has shown, for hurricanes the temperature differential that matters is between the sea-surface temperature and the storm outflow, and this gives an upper bound to hurricane intensity.

        Which is what I said – it is the gradient, not the absolute level that matters.

        Unfortunately for the theory, the accumulated cyclone energy doesn’t indicate a rise.

      • TE, anyway, as I said, I do see a connection between a hot El Nino and what is going on in the Pacific at this time even if you don’t.

      • Sure, the warm northern tropics and mid latitudes of the pacific during el nino will increase temperature gradients, particularly going into the fall and winter months. So what does this have to with GHGs? They probably contribute to the IPWP, but not a lot. The IR is a very small percentage of the energy going into the pacific and IR doesn’t get absorbed by the ocean quite as much ans SW. It’s winds that drive the build up of warm water for el nino, and winds will increase evaporation further reducing the GHG contribution. The IR contribution is likely very slight. GHGs might make an el Nino longer in duration, slowing the release during el Nino, particularly if winds are weak, but we also need to wonder about cloud responses and precipitation. Spencer found that albedo over the ocean sometimes declines slightly during el Nino. What are the differences in outgoing SW and LW during night and day?

        It’d be smart to look at albedo over the relevant region over time and night and day outgoing LW.

      • TE, anyway, as I said, I do see a connection between a hot El Nino and what is going on in the Pacific at this time even if you don’t.

        But you’re seeing this connection, which is apparent in the Eastern Pacific, while ignoring the anti- correlation of tropical cyclone energy and temperatures in the Atlantic.
        Also, the Western Pacific has had higher ACE this year, but on average, near normal SSTs:

    • Haha… Actually Funny :-)

  25. Very nice summary of the “consensus”, Judy.

    I think the community figured out that the historical datasets were not of sufficient quality to provide satisfactory answers e.g. tease out the globall warming signal.

    Modeling studies also have provided rather incomplete pictures of tropical cyclone activity in a much warmer climate. Fewer but more intense seems to be the conservative consensus position as described in IPCC SREX and AR5.

    In 2025, we’ll look back at a decade of exciting Pacific typhoon activity and the continuation of the now (mostly certain) Atlantic -AMO inactive period. Back to The Future of the 1980s.

    • Interesting suppliment to the above from Dr. Maue.

      Ensure if you read it, you read it all.

      http://www.gfdl.noaa.gov/historical-atlantic-hurricane-and-tropical-storm-records

      By the way, I referenced your astute observation on the Cape Verde 1892 cyclone earlier, kinda. There is no substitute/model for history to date.

    • > In 2025, we’ll look back at a decade of exciting Pacific typhoon activity and the continuation of the now (mostly certain) Atlantic -AMO inactive period.

      Is that prognosis based from the poor historical dataset or the incomplete modeling studies, Ryan?

      • More likely based on his expertise in the field.

        Your field expertise appears to extend only to fertilizing them with your presence.

      • Why would science need historical datasets and modeling studies if all it takes is field expertise to make a prognosis contrarians would gobble, timmy boy?

      • I don’t know willard. Why don’t you tell me? You’re the all knowing twit here.

        Gimme a T, gimme a W, give us a break from willard the twit.

      • That’s great, timmy boy. Denizens can appreciate your teaching experience right there.

      • Its intution

      • timg56

        Surely you must see what Ryan is doing.
        The goal of science is understanding and prediction
        and the measure of understanding is skill in prediction.
        and its important that people be able to audit or examine
        the basis of your understanding, and to check your predictions.

        How does one build understanding?
        Its a good thing to have data.
        Its a good thing to have some sort of theory, some sort of way
        of computing consequences for your understanding.

        1. Ryan throws out data. it’s no good.
        2. Ryan throws out models, there no good.
        3. Ryan then makes a prediction, based on what?

        We don’t know what data he accepts and why. If we did know the data we could question his prediction without even waiting.
        We dont know his method for calculating consequences. if
        we did we could rule it out or decide it may be plausible.

        What you have instead is someone using his expertise to get you to trust him. Hmm. homey dont play that game

      • Steven Mosher: “Its a good thing to have data.”

        And it’s even better if you don’t Mannipulate the data to match the computer games climate models!

      • “The goal of science is understanding and prediction”

        Yer a funny guy.

      • Steven M, are you not asking that we trust your group’s expertise when considering your use of TOB, as one simple example, when doing your calcs? How does your intuition fit into those adjustments?

      • Steven Mosher: 1. Ryan throws out data. it’s no good.
        2. Ryan throws out models, there no good.

        He did not throw them out. Here is what he wrote:

        I think the community figured out that the historical datasets were not of sufficient quality to provide satisfactory answers e.g. tease out the globall warming signal.

        Modeling studies also have provided rather incomplete pictures of tropical cyclone activity in a much warmer climate. Fewer but more intense seems to be the conservative consensus position as described in IPCC SREX and AR5.

        Then he wrote his expectation for the coming decade (exciting in the Pacific, continuation of mostly low AMO in the Atlantic), based on data to date, some of which he has published in peer-reviewed journals, some of which he has posted on line. Even all the data together of all kinds collected over the next decade will probably not be sufficient to provide satisfactory answers, such as to tease out the global warming signal.

      • > I think the community figured out

        The word “community” does not seem quite accurate.

        ***

        > Then he wrote his expectation for the coming decade (exciting in the Pacific, continuation of mostly low AMO in the Atlantic), based on data to date, some of which he has published in peer-reviewed journals, some of which he has posted on line.

        Citation needed.

        For now, the “community” turns out to be RyanM.

    • “The study also shows that for Cairns, Australia, a 5.7-meter (18-foot) storm surge is possible…”

      I guess it must be possible. While tide and terrain make for too much variation for neat comparisons, Far North Qld has already experienced an estimated 13 metre storm surge during Cyclone Mahina in 1899. Nothing is certain about that mess, but they were picking porpoises off the cliffs after. There is dispute about the height but one local authority, a constable, reported 15 metres at Barrow point. The surge travelled 5k inland and the forest still has trouble re-establishing in the salty ground there. It’s still “officially” the world record surge, though that’s likely a bit of a factoid.

      Yasi, a brute of a cyclone in 2011, produced an estimated 7m storm surge just 138k north of Cairns. Innisfail, not far north of Cairns, has experienced a couple of real annihilators, in 1918 and 2006. The 1918 debris went 7 metres into the trees, but I get the impression storm surges are a matter of geography, luck and opinion.

      So 5.7 metres possible? I’d say even 5.75!

      What’s surprising is that people express surprise when hurricanes of enormous force occur in long recognised hurricane belts. What’s that all about?

      And now, well away from cyclone country, when NSW cops one of its drenchings it’s a brand new and terrifying device called an “East Coast Low”. Just in case we mix it up with those ordinary old drenchings of the flapper era and Beatles era – which also happened to produce as much rain in as short a time!

    • Innisfail is south of Cairns but your point remains valid Mosomoso. Natural variability comes in many shapes and sizes but TonyB will tell you that historical incidences of extreme weather events are deemed by climate science as “anecdotal” and of no significance.

    • South it is, Peter!

      Innisfail is a good spot for extremes. I don’t know if it holds the Australian record for most rain in a day and month, but the half-metre + it copped on individual days in 1903 and 1913 sounds awesome. Since 1887, Jan, Feb, March and April all set records over a metre and half.

      And in 1950, the year eastern Oz nearly floated away (while the west baked), Innisfail managed nearly 6 metre of rain. Where did they put all that?

      Like most of Oz, Innisfail had its driest year in 1902…but sssh.

      The point here is that, if certain of the above extremes were to occur now, they would cease to be quaint anecdotes and become doom science. You know the drill.

      • Innisfail is reputed to be the wettest place in Oz and yes, its amazing that the surrounding area hasn’t been washed out to sea by now!

      • Peter, I’ve seen figures of nearly 8 metres for Tully in 1950. That was a year! I was born in 1949 and could not get a hold of the whole droughty Australia thing received from parents, grandparents and bush lore. Then came some climate change in the 1960s and I got it. But then the stormin’ 70s etc etc…

      • moso, I looked at a lot of dodgy government-backed projects in Queensland, but the 1990s Tully Millstream Hydro project seemed very viable. It was opposed by whitewater rafters et al and dropped. Amazing that if the various ALP government’s desire to cut GHG emissions was genuine, that they didn’t resurrect the plan. Perhaps they got rainfall forecasts from Flim Flammery, the paleologist turned climate go-to guru for the ALP.

      • I suppose we have to consider what sort of world we want to leave to white water rafters’ grandchildren, who may also want to go white water rafting. Not to mention the grandchildren of the white water rafters’ grandchildren. Heaven knows, a time could come when white water rafters have to travel to a different river for their sport. Those will be the times which try white water rafters’ souls!

        Well, at least you tried, Great Cunn.

  26. From a retired high school teacher who taught AP classes.

    Most often, I began the year with the well known Mark Twain, (silly to the extreme) story, to which he made the following conclusion (approximately)
    ‘There is something fascinating about science, one gets such a wholesale return of conjecture on such a trivial investment of fact’

    I use this thread mainly to learn, and rarely comment, but here I have to make a general observation.

    In general, climate science has taken a mega-quantum leap to ‘The Science is Settled’ when in fact most aspects should simply be at the hypothesis stage. I doubt there is much that would make a workable theory in most any aspect of climate science.

    Too many unknowns, and unknown unknowns.
    Oscillations of many different lengths from known and unknown forcing s.
    I am by no means qualified to make any kind of judgement here, except that the valid observational period seems to be simply much too short.
    I expect there are forcings which may not have materialized in the observational period here. The one possible conclusion is giving more credence to the significance of a stadium wave hypothesis.

    I think so many in the science world lose, when getting too close to happenings, the fact that the beautiful blue ball is always out of equilibrium regionally and as a whole. Through negative feedback it is always in relative acceleration to an equilibrium point (or multitude of points) the value of which is unknown, but I think would be of value to try to find, or get closer. to.

    Nevertheless I have learned more today.
    ,

  27. The moment when the unusually powerful hurricane Katrina hit New Orleans, in the summer of 2005, people insisted on being informed and on understanding the phenomenon. Let’s assume that winter temperatures turn suddenly to Ice Age conditions (not experienced for more than one hundred years), but no one talks about this because there is a war going on. That was the case during the winter of 1939/40, when, in several locations in Northern Europe, average temperatures were more degrees lower than during the previous century, and the WWII war machinery cooled down the earth for four decades. If this investigation succeeds in proving that two major wars changed the course of the climate twice in the last century, it will also prove that shipping, fishing, off-shore drilling, and other ocean uses had constantly contributed to the global warming since the start of industrialization, more than 150 years ago. A new chapter on the climate change issue could be now opened, giving more attention to oceanic phenomena under the influence of the potential of the “1982 United Nations Convention on the Law of the Sea” . All research would lead to a better understanding and protection of the stability of our short-term weather and long-term global climate. Here are some research on the subject I’m talking about: http://www.1ocean-1climate.com. What do you think on that?

  28. Pingback: The 9th Inning of Summer | WOODTV.com Blogs

  29. mosomoso – Thanks for pointing out the deficiency of my due diligence! Article duly updated:

    My tongue was of course firmly in my cheek when I said “Unless someone spots an error in my due diligence!”. The cue I was referring to was of course this very article of Judith’s.

  30. stevenreincarnated

    Here’s a recent reconstruction of hurricane activity:

    http://www.nature.com/articles/srep12838

    “Our results corroborate evidence for the increasing trend of hurricane activity during the Industrial Era; however, we show that contemporary activity has not exceeded the range of natural climate variability exhibited during the last millennium.”

  31. Sorry, this is OT, but very important considering the timing WRT Paris and who wrote it. It looks really convenient for the warmistas. From the article:

    Layzej writes with news carried by The Guardian about a report published by the Global Perspectives & Solutions division of Citibank (America’s third-largest bank) examining the costs and benefits of a low-carbon future. The report examined two hypothetical futures: one “business as usual,” and the other (the “Action” scenario) which includes an aggressive move to reduce energy use and carbon emission. From the article:
    “One of the most interesting findings in the report is that the investment costs for the two scenarios are almost identical. In fact, because of savings due to reduced fuel costs and increased energy efficiency, the Action scenario is actually a bit cheaper than the Inaction scenario. Coupled with the fact the total spend is similar under both action and inaction, yet the potential liabilities of inaction are enormous, it is hard to argue against a path of action.”
    But there will be winners and losers, says the report: “The biggest loser stands to be the coal industry, where we estimate cumulative spend under our Action scenario could be $11.6 trillion less than in our Inaction scenario over the next quarter century, with renewables, wind and nuclear (as well as energy efficiency) the main beneficiaries.”

    http://hardware.slashdot.org/story/15/09/01/1618247/citi-report-slowing-global-warming-could-save-tens-of-trillions-of-dollars

    • Has citi asked for any political favors lately, or received any in recent history? I can’t seem to recall.

      This analysis is striking, since a corporation of their skill set certainly wouldn’t benefit from convoluted regulation and additional accounting requirements.

      ;)

      • I wouldn’t trust anything out of Citi since John Reed left. It was one of the biggest players in the 2007/2008 crisis.

        This analysis is striking, since a corporation of their skill set certainly wouldn’t benefit from convoluted regulation and additional accounting requirements.

        Actually, as a very large player, they have a competitive advantage dealing with complex, obfuscatory regulations, relative to smaller players. It costs the same amount to keep the necessary staff to understand the regulations, but that staff can help manage a larger amount of investment.

        Also, they’re in a (relatively) better position to influence the details of regulations than smaller organizations.

      • I’ve been re-reading the Final Report of the National Commission on the Causes of the Financial and Economic Crisis in the United States, found a telling quote in chapter 2:

        Put simply and most pertinently, structured finance was the mechanism by which subprime and other mortgages were turned into complex investments often accorded triple-A ratings by credit rating agencies whose own motives were conflicted. This entire market depended on finely honed computer models—which turned out to be divorced from reality—and on ever-rising housing prices. When that bubble burst, the complexity bubble also burst: the securities almost no one understood, backed by mortgages no lender would have signed 20 years earlier, were the first dominoes to fall in the financial sector. [my bold]

        Amazing how naive trust in “finely honed computer models” managed to jump from “Long Term Capital Management”, to the entire banking industry’s risk pricing for derivatives, to “Chicken-Little” climate alarmism.

        Or maybe not: the models, and the naive dependence by activists, were already around in 1997 when I first heard about “global warming”.

      • Thanks AK.

        Of course, I was being sarcastic.

        In addition, I believe Citi recently called for support to prop up China and IIRC they are part of the current real-estate bubble and/or looking to sell rent backed bond products (which are currently inflated by Dodd-Frank and post bubble mortgage lending aversion and inadequate post bubble building relative to population growth).

        It’s amazing that all of this this isn’t obvious to people.

        They’re taking advantage of the need to prop up economies in europe and markets in the us during the election year. How do you think the Iran deal evolved. Sanction to prevent bomb building were probably futile. Europe needed the oil to keep economic pressure off the broader population and prevent civil unrest in fragile economies. The US needed low oil prices to protect incumbant politicians in the up coming election year. Low oil prices also strain over-leveraged oil producing enemy nation states, like venzuela. Probably USSR too.

    • How do they levelize the output of wind and solar? What is the assumed cost of capital? The ELCC of wind is about 13%, for solar at low penetration it is on the order of 50%, much lower at higher penetration. How do you invest in solar and wind without also investing in extra infrastructure to account for the above?

  32. OT but interesting.

    The geniuses who run the US government, just as certain of globalclimatewarmingchange as the IPCC, have allowed the number of US ice breakers to fall to…2.

    The Soviets, sorry, fascist Russians, have 41, with 11 more in the pipeline. And are “making a play” for the Arctic.

    http://www.foxnews.com/politics/2015/09/01/ice-war-cometh-russia-makes-play-for-arctic-obama-seeks-more-navy-icebreakers/?intcmp=hpbt1

    But don’t worry, the acolytes of the religion of the imminent ice free Arctic have placed orders for more ice breakers.

    Due in 2020.

  33. Hi Judith. Nice summaries and data!
    In my view, 1988 and 1989 data should be included in the Landsea study and it should be analyzed by year, not by pentad. In the Holland study I’m concerned that there’s a conflating relationship between ACCI and measurement technique. In other words, high ACCI likely occurred in periods (1990s, 2000s) when wind estimation techniques were better (and captured peak intensities better), conflating their analysis.
    Historical data is generally too poor in quality and duration to reliably detect weaker trends or to separate natural from anthropogenic effects. It will take much more than ten years of additional data to change that. The good news is that the sky has not fallen (ie, we’ve not seen a strong increase in intense TCs).

    • Hi David, long time since we’ve talked hurricanes!

      • David and Judith: When the reliability of data varies with time, analysis of time series is problematic. More importantly, time doesn’t directly change hurricane intensity; time is a proxy for increasing SST beneath the track of hurricanes. A poor proxy for warmer SSTs. If you want to know whether GW will increase the proportion of Category 4/5 storms, why not see if warmer SST actually increases the probability of a TC intensifying. Instead of being limited to perhaps 30 years of data (less due to autocorrelation), you’d have 700 TCs per decade with constant observation methodology.

  34. Looking at their main figure of Landsea, Klotzbach and olland we see that categories 1, 2, and 3 all declined by 10 percent within the last 40 years. The exceptions are categories 4 and five whose frequency doubled over the same period. They try to explain it by pleading poor observations prior to 1989. I simply do not believe them. Categories four and five hurricanes are far easier to observe than the three lower categories are. This fact eliminates observational errors as a cause of the discrepancy involved. Based on the data they show we must assume that the increase of category 4 and 5 is probably real. Unfortunately they chose to cut the observation period short despite the available time line that extends to the early part of the century. Without seeing these data that were left out a firmer judgement of category four and five frequency is difficult to arrive at. As to sorting out natural from human-caused hurricanes, just relax. There are no human-caused hurricanes.

  35. Judith: Graphs with year as the independent variable and hurricane intensity as the dependent variable don’t tell us anything useful about GW and hurricanes. Time isn’t increasing the intensity of hurricanes! (Worse, our measurement technology has changed with time.) Rising GMST isn’t increasing the intensity of hurricanes! Rising SSTs aren’t increasing the intensity of hurricanes! Changes in SSTs UNDER the path of hurricanes could be changing the intensity of hurricanes. (Hurricanes are heat engines powered by a temperature difference, so SST may not be the critical temperature parameter.)

    So where is the data showing that hurricanes intensify more when they pass over warmer water? If this year’s record breaking percentage of Cat 4/5 hurricanes haven’t passed over warmer water than hurricanes during recent years when the percentage was much lower, then GW won’t increase the intensity of the average hurricane in the future.

    Intensity vs time data suggests that more Cat 3 hurricanes are intensifying to Cat 4/5 because of global warming. This suggests focusing specifically on SST under the Cat 3 portion of the track. Fewer tropical storms are becoming tropical cyclones, so SSTs before this transition would make an interesting control. (No, I won’t believe that warmer SSTs make one transition harder and the other easier.)

    FWIW, the Pat Michaels’ 2006 GRL paper says the correlation between SST and TC wind speed is low in the Atlantic. The observed increase in maximum wind speed with maximum SST is about 5% per degC. The difference between the average Cat 3 and Cat 4 is 17% (or 3 degC of SST warming). Figure 3 shows that an SST of 28 degC appears to be a threshold for producing a Cat 3 storm, but further increases in SST didn’t increase intensity.

    http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.495.4998&rep=rep1&type=pdf

    • I’m not a climate scientist and don’t play one on TV but…

      What is the relationship of saturated lapse rate (MALR) and class 4/5 cyclones/hurricanes?

      Is this information available?

      One would expect that for a heat engine the greater the differential between source and sink the more efficient the engine.

      Does CO2 or average global temperature have any effect on MALR in the tropics?

      • PA: Wikipedia says that an unstable atmosphere (lapse rate?) is necessary for hurricane development. When the lapse rate exceeds the MALR, then a parcel of air that rises, expands and cools will still be warmer and less dense than the surrounding air. That parcel will continue to rise. In regions above the boundary layer that are well mixed by convection, the lapse rate tends to be near the MALR on the average, but the lapse rate measured by radiosondes actually show large deviations at any moment due to weather and turbulence. In theory, convection will continue until enough heat has carried upward so that an unstable lapse rate no longer exists.

        Everyone talks about the importance of SST to powering hurricanes, but no one pays any attention to the temperature difference that powers a hurricane’s heat engine. If SSTs and the upper atmosphere warm at the same rate, then that heat engine is operating with the same temperature difference (plus about 7% more latent heat per degC of surface warming). Do all hurricane reach the same height above the surface, possibly the tropopause, or do some get more power by reaching higher?

        From Wikipedia, showing how lapse rate is ignored: “Dr. Kerry Emanuel created a mathematical model around 1988, called the maximum potential intensity or MPI, to compute the upper limit of tropical cyclone intensity based on sea surface temperature and atmospheric profiles from the latest global model runs. Maps created from this equation show values of the maximum achievable intensity due to the thermodynamics of the atmosphere at the time of the last model run (either 0000 or 1200 UTC). However, MPI does not take vertical wind shear into account.[8] MPI is computed using the following formula:

        V = A + B * exp{C(T-T_0)}

        Where V is the maximum potential velocity in meters per second; T is the sea surface temperature underneath the center of the tropical cyclone, T_0 is a reference temperature (30˚C) and A, B and C are curve-fit constants. When A = 28.2, B = 55.8, and C = 0.1813, the graph generated by this function corresponds to the 99th percentile of empirical tropical cyclone intensity data.”

      • That analysis seems right. The peak SST in the Caribbean is the start of August.

        The last week of August to the first week of November period is when the worst hurricanes occur. The atmosphere is cooling relative to the ocean which would maximize the differential – so the SST isn’t the issue, the differential appears to be the important factor.

  36. QOTD: “If we do nothing, Alaskan temperatures are projected to rise between six and twelve degrees by the end of the century ” -BO

    View story at Medium.com

    Andrew

    • I’ve got to say that I found it surprising that the POTUS would say that after “A Disgrace To The Profession” by Mark Steyn became available for download from Amazon yesterday!
      Hopefully, he hasn’t had time to read it yet and will issue a correction as soon as he’s read it.

    • Joe Biden must be his climate advisor.

  37. I always thought Hurricanes and Tornadoes were caused by temperature transitioning or uneven heating just like wind? Warm air bumping into cold air or something along that lines? So even though the Atlantic is on the cold side right now there is still bands of hot places?

  38. more about CA levees, from the 21 Aug issue of Science, vol 349, p 799. Note reference to Australia and Texas.

    Drought threatens
    California’s levees
    CALIFORNIA HAS MORE than 21,000 km
    (1) of earthen embankments (referred
    to as levees) that protect dryland from
    floods and also function as water storage
    and management systems. The resilience
    of these levees under the record drought
    conditions California faces is an emerging
    issue that requires attention.
    Prolonged droughts undermine the
    stability of levee systems by increasing
    water seepage through soil, soil cracking,
    soil strength reduction, soil organic carbon
    (SOC) decomposition, and land subsidence
    and erosion (2). The sand-clay mixtures,
    which form the body of the levees and
    consequently the entire structure, can lose
    a substantial amount of strength under
    dry conditions. Furthermore, levees in
    California are built on peaty soils, and
    the extreme drought leads to greater
    SOC decomposition in these soils. A large
    amount of the global carbon stock is found
    in peaty soils, and ~25% of this estimated
    stock is predicted to diminish under
    extremely dry conditions (3). Oxidation of
    SOC under a prolonged drought can also
    accelerate land subsidence. In fact, 75% of
    the land subsidence across California is
    accredited to oxidation of SOC (3). Land
    subsidence can increase the risk of water
    rising over the top of the levees.
    Australia’s Millennium Drought (1997–
    2009) is often considered the type of event
    for which California should prepare (4). At
    the peak of the drought (i.e., 2008 to 2009),
    Australia experienced disastrous failures of
    alluvial river banks along the Murray River
    (5). Similar failures occurred in other parts
    of the world during extreme drought conditions,
    such as the 2003 Wilnis Levee failure
    in the Netherlands (6).
    California’s drought is yet another
    stress that poses a great risk to an already
    endangered levee system. At this time,
    55% of California’s levee systems are
    rated as “high hazard,” meaning that
    they are in danger of failing if a flood
    event or an earthquake occurs (1). This
    indicates that California’s levee systems
    have a high failure risk without even
    considering an extreme event such as a
    prolonged drought. If the drought ends
    with heavy rainfall-induced flooding, as
    seen in 2010 in Australia (5) and 2015 in
    Texas and Oklahoma (7), the levees could
    be at even greater risk. Drought risk and
    potential changes in the future climate
    were not considered in the engineering
    design of these levee systems and
    are still not considered in maintenance
    guidelines today. There is an urgent need
    to invest in research on (i) effects of the
    rate and variability of drought on the
    short- and long-term behavior of levees;
    (ii) constraints in existing levee design,
    maintenance, and monitoring guidelines
    for extreme droughts; (iii) adaptation and
    mitigation strategies for reducing drought
    impacts on the performance of levee systems;
    (iv) socioeconomic consequences of
    levee failures; and (v) multi-hazard disaster
    risk science to assess the impacts of compound
    and consecutive extreme events on
    levees. Community engagement, public risk
    education, and close collaboration with
    stakeholders are key to enhancing societal
    resilience of levees to extreme droughts.
    Farshid Vahedifard,1
    * Amir
    AghaKouchak,2 Joe D. Robinson1
    1Department of Civil and Environmental
    Engineering, Mississippi State University,
    Mississippi State, MS 39762, USA. 2Department of
    Civil and Environmental Engineering, University of
    California, Irvine, CA 92697, USA.
    *Corresponding author. E-mail: farshid@cee.
    msstate.edu
    REFERENCES
    1. California Department of Water Resources, Flood Control
    System Status Report [Central Valley Flood Management
    Planning (CVFMP) Program, California, 2011];www.water.
    ca.gov/cvfmp/docs/FCSSRDec2011_FullDocument.pdf.
    2. P. Vardon, Env. Geotechnics 2, 166 (2014).
    3. B. A. Brooks et al., San Francisco Estuary Watershed
    Sci. 10(1) (2012); http://escholarship.org/uc/
    item/15g1b9tm.
    4. A. Aghakouchak et al., Science 343, 1430 (2014).
    5. E. V. De Carli, T. C. T. Hubble, in Proceedings of the 7th
    Australian Stream Management Conference, G. Vietz, I.
    D. Rutherfurd, R. Hughes, Eds. (Townsville, Queensland,
    Australia, 2014), pp. 255–261.
    6. S. Van Baars, Géotechnique 55, 319 (2005).
    7. A. Freedman, A. Li, “Texas and Oklahoma hit by
    severe flooding, killing 2” (2015); http://mashable.
    com/2015/05/24/texas-oklahoma-flash-flooding/.

  39. Jubilation! today I received my signed copy of Mark Steyn’s book, “A disgrace to the profession.”

    • Gives us your thoughts on the book MattStat. They would be valued by all unbiased commenters here!

      • Peter Davies, I think everyone already has a pretty good idea of what is in the book. The body is a collection of quotes, from 120 scientists, that are critical of the hockey stick or Mann, some going so far as to call it “fraudulent”; the title comes from one of those quotes critical of Mann. The quotes antedate Mann’s suit against Steyn, thus supporting a claim that Steyn’s use of the word “fraudulent” was not based on a reckless disregard.

        It is not an unbiased review of the climate science, but it does not claim to be. It is not an unbiased review of all opinions of Mann, but it does not claim to be that either. It is essentially a long disputation of claims by Mann in his court filings. After 120 quotes critical of Mann, it is followed by 4 quotes supportive of Mann.

        It opens with a short review, from Steyn’s perspective, of the controversy surrounding the hockey stick, and brief notes about the suits, including that no one has filed an amicus curiae lawsuit on behalf of Mann in Steyn v Mann. Each quote is then introduced with a brief bio, with lots of letters denoting degrees, awards, appointments and such, of the author of the quote. That is followed by the quote or quotes, and Steyn’s perspective of how the quotes fit into the discussions, or context, in which each quote was written or uttered; and this is where evidence in support of the quotes, critical of Mann, critical of the use of a small number of bristlecone pines etc, occasionally quotes supportive of Mann that are then critiqued, is presented.

        It does not have much science or other information that will be new to most readers. I bought it in order to support Steyn in his legal disputes, as I had earlier bought “The Satanic Verses” to support Rushdie. What might make an impression on Climate Etc readers is that there were 120 such quotes already public when Steyn published the phrase “fraudulent hockeystick” in the opinion piece that drew the lawsuit. Compared to the reading of a few blogs and editorials in diverse places over a long time span, there is a feel of solidity in 290 bound pages of critical commentary. even though the print is big. Who knew that many scientists had been publicly critical of Mann? I had thought that the number was less than 20.

      • If Steyn loses this case, it’s just one more confirmation the US government is in the dumper.

      • oops, a correction. Not every quote is from a scientist. Some are science journalists, such as Dan Greenberg. Some are from anonymous referees of papers in in review.

      • Thanks Matthew. I was aware of the general content of the book and that the majority of these comments antedate the suit by Mann. These comments certainly supports Steyn’s defence that the use of the word “fraudulent” were not made maliciously. What I was wondering was whether these comments were all in the public domain and not generally of a private nature? If some of these comments were indeed of a private nature then it seems that they might be inadmissable as evidence in the forthcoming trial.

  40. Where’s the water vapor?

  41. Pingback: SURVIVALISTS BLOG | Hurricanes and global warming: 10 years post Katrina | Climate Etc.

  42. Pingback: Weekly Climate and Energy News Roundup #195 | Watts Up With That?

  43. WASHINGTON (AP) — A new but controversial study asks if an end is coming to the busy Atlantic hurricane seasons of recent decades.

    The Atlantic looks like it is entering in to a new quieter cycle of storm activity, like in the 1970s and 1980s, two prominent hurricane researchers wrote Monday in the journal Nature Geoscience.

    Scientists at Colorado State University, including the professor who pioneered hurricane seasonal prognostication, say they are seeing a localized cooling and salinity level drop in the North Atlantic near Greenland. Those conditions, they theorize, change local weather and ocean patterns and form an on-again, off-again cycle in hurricane activity that they trace back to the late 1800s.

    Warmer saltier produces periods of more and stronger storms followed by cooler less salty water triggering a similar period of fewer and weaker hurricanes, the scientists say. The periods last about 25 years, sometimes more, sometimes less. The busy cycle that just ended was one of the shorter ones, perhaps because it was so strong that it ran out of energy, said study lead author Phil Klotzbach.

    Klotzbach said since about 2012 there’s been more localized cooling in the key area and less salt, suggesting a new, quieter period. But Klotzbach said it is too soon to be certain that one has begun.

    “We’re just asking the question,” he said.

    But he said he thinks the answer is yes. He says the busy cycle started around 1995 and probably ended in 2012; in 2005 alone, Katrina, Rita and Wilma killed more than 1,500 people and caused billions of dollars of damage. The quiet cycle before that went from about 1970 to 1994 and before that it was busy from 1926 until 1969, he said.

    http://hosted.ap.org/dynamic/stories/U/US_SCI_FEWER_HURRICANES?SITE=AP&SECTION=HOME&TEMPLATE=DEFAULT&CTIME=2015-09-07-11-03-44

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