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So how did that global cooling bet work out?

Filed under: — group @ 22 November 2010

Two and a half years ago, a paper was published in Nature purporting to be a real prediction of how global temperatures would develop, based on a method for initialising the ocean state using temperature observations (Keenlyside et al, 2008) (K08). In the subsequent period, this paper has been highly cited, very often in a misleading way by contrarians (for instance, Lindzen misrepresents it on a regular basis). But what of the paper’s actual claims, how are they holding up?

At the time K08 was published, we wrote two posts on the topic pointing out that a) the methodology was not very mature (and in our opinion, not likely to work), and b) that the temperature predictions being made (for the 10 year overlapping periods Nov 2000-Oct 2010, Nov 2005-Oct 2015 etc.), were very unlikely to come true. These critiques were framed as a bet to see whether the authors were serious about their predictions, similar in conception to other bets that have been offered on climate related matters. This offer was studiously ignored by the scientists involved, who may have thought the whole exercise was beneath them. Oh well.

However, with the publication of the October 2010 temperatures from HadCRUT, the first prediction period has now ended, and so the predictions can be assessed. Looking first at the global mean temperatures…

we can see clearly that while K08 projected 0.06ºC cooling, the temperature record from HadCRUT (which was the basis of the bet) shows 0.07ºC warming (using GISTEMP, it is 0.11ºC). As in K08 this refers to T(Nov 2000:Oct 2010) as compared to T(Nov 1994:Oct 2004). For reference, the IPCC AR4 ensemble gives 0.129±0.075ºC (1\sigma) (and a range of -0.07 to 0.30ºC related to internal variability in the simulations) (using full annual means).

More interestingly, we can look at the regional pattern. The K08 supplemental data showed their predicted anomaly along with anomalies from a free-running version of their model the standard IPCC results for the 2005-2015 period (which is half over), rather than the 2000-2010 period, but the patterns might be expected to be similar:

The anomalies are with respect to the average of all the decadal periods they looked at, which is roughly (though not exactly equal to) a 1955-2004 baseline. The actual temperature changes for 2000-2010, using GISTEMP for convenience, look like this:

It is striking to what extent they resemble the spatial pattern seen in the AR4 ensemble free-running version rather than the initiallised forecast, though there are also some correlations there too (for instance, west of the Antarctic peninsula, related to the ozone-hole and GHG related increase in the Southern Annular Mode).

It is worth emphasising that the RC bet offer was not frivolously made, but reflected some very clear indications in the paper that the predictions would not come true (as explained in our second post). Specifically, their ‘free’ model run, without data assimilation, performed better in hindcasts when compared to observed data, i.e. the new assimilation technique degraded the model performance. Both previous hindcasts showing cooling of the model were wrong. Since global warming took off in the 1970s, the observed data have never shown a cooling in their chosen metric (ten-year means spaced 5 years apart). Other climate models run for standard global warming scenarios only rarely show this level of cooling. On the other hand, there is a simple explanation for such a temporary cooling in a model: an artifact known as ‘coupling shock’ (e.g. Rahmstorf 1995), which arises when the ocean is switched over from a forced to a coupled mode of operation, something that has no counterpart in the real world.

The basic issue is that nudging surface temperatures in the North Atlantic closer to observed data would probably nudge the Atlantic overturning circulation in the wrong direction since changing the temperature without changing the salinity will give the opposite buoyancy forcing to what would be needed. The model indeed shows negative skill in the critical regions of the North Atlantic which are most affected by the overturning circulation. All this can be seen from the paper. Last but not least, by the time the paper was published three quarters of the 2000-2010 forecast period were over with no sign of the predicted cooling – barring an unprecedented massive temperature drop, the prediction was always very unlikely.

Was this then an “improved climate prediction“? The answer is clearly no.

So what can we conclude? First off, the basic idea of short term predictions using initialised ocean data is a priori a good one. Many groups around the world are exploring to what extent this is possible, and what techniques will be the most successful. However, before claiming that a new methodology is an improvement on other efforts and that it predicts a very counter-intuitive result, a lot of effort is required to demonstrate that even theoretically or in ideal circumstances that it will work. This can involve ‘perfect model’ experiments (where you test to see whether you can predict the evolution of a model simulation given only what we know about the real world), or hindcasts (as used by K08), and only where there is demonstrated skill is there any point in making a prediction for the real world. It is nonetheless important to try new methods, and even when they fail, lessons can be learned about how to improve things going forward.

It is perhaps inevitable that novel prediction methods that appear to ‘go against the mainstream’ are going to be higher profile than they warrant in retrospect – such is the way of the world. But scientists need to appreciate that these high profile statements will be taken and spread far more widely than they possibly anticipate. Thus it behoves them to be scrupulous in explaining the context, giving the caveats and making clear the experimental nature of any new result. This is undoubtedly hard, especially where there are people ready to twist anything to fit an anti-AGW agenda, but we should at least try.

Note, we asked Noel Keenlyside if he wanted to comment on our assessment of their prediction, and he declined to do so. We would be still be happy to post any of his or his co-authors comments in response though.

Update Dec 2: The Stuttgarter Zeitung newspaper (in German) followed up on this and got the following comments from the authors:


“The forecast for global mean temperature which we published highlights the ability of natural variability to cause climate fluctuations on decadal scale, even on a global scale. I am still completely convinced that this is correct.”


“I do not want to comment on this.”

Then an indirect quote: the fact that warming for 2000-2010 was greater than predicted in their study does in itself not speak against their study, and then

“You have to look at this long-term. I would not weigh a few years earlier or later too much.” But if the forecast turns out to be wrong by 2015, “I will be the last one to deny it”.

252 Responses to “So how did that global cooling bet work out?”

  1. 201
    Hank Roberts says:

    > CO2 is less of a GHG than water vapor
    OK so far
    > which it replaces
    Citation needed! Why do you imagine CO2 “replaces” water vapor?

  2. 202
    Hank Roberts says:

    PS for Wayne Justice,

    > less of a GHG
    probably doesn’t mean what you think it does, considering your logic above.

    See, for example:

  3. 203
    S. Molnar says:

    OT (sorry) – I notice that with publication date approaching (Available 31 December from all fine purveyors of atmospheric sciences textbooks!), raypierre is sticking his head above the trenches a bit more often. Is there any chance of some liveblogging of the Fall AGU meeting?

  4. 204

    181 (Rod B),

    Thank you for so kindly responding with:

    So the answer to my question in 168 is ‘yes’? just checking.

    It adds a nice emphasis to my point that:

    They [deniers] tremble at the thought of having their own incomes or lives impacted as a result of any actual action taken…

  5. 205
    J says:

    Last year the Met said the mean world temperature for 2010 is expected to be 14.58C, the warmest on record.

    How’s that prediction going?

    [Response: I doubt that the met office made any such specific claim, however there was a strong likelihood that 2010 would be the warmest global anomaly on record, and indeed it is running very close in multiple datasets. – gavin]

  6. 206
    Brian Dodge says:

    “I understand both the solar change and how/why the solar change affects planetary temperature.”William — 4 December 2010 @ 9:31 PM
    “When I say I know how and why the sun changes and how the solar changes affect climate, that is to say I know that because I have read the papers and studied that subject.” William — 5 December 2010 @ 2:50 PM
    “Therefore, more CO2 should cool the planet.” Wayne Justice — 5 December 2010 @ 4:06 PM

    Since you guys know how the sun and CO2 influence the climate, perhaps y’all can explain this?

  7. 207
    Brian Dodge says:

    “When I say I know how and why the sun changes and how the solar changes affect climate, that is to say I know that because I have read the papers and studied that subject.” William — 5 December 2010 @ 2:50 PM
    “Therefore, more CO2 should cool the planet.” Wayne Justice — 5 December 2010 @ 4:06 PM

    Since you guys know how the sun and CO2 influence the climate, perhaps y’all can explain this?

  8. 208
    Brian Dodge says:

    “So I, as a FF vehicle owner, have to pay for half of my neighbor’s new hybrid AND further subsidize his driving by paying a bunch more than he for gasoline — is this correct?”

    No. What you have to do is reimburse society for the continuing damage caused all the CO2 you thoughtlessly dumped into the atmosphere previously, and will continue to do by burning FF in your car. The more sh*t you dump into our common atmosphere, the more you pay, just like the rest of us.

    The people in Bangladesh, and the Maldives, and the people who died, or have to pay for the cleanup or crop losses in the floods in Guatemala, and France, and Spain, and Wales, and Fiji, and Australia, and China, and, and, and… will pay or are paying disproportionately for your and my FF use.

    – a few selections from google searches for “record rainfall”+flooding – About 36,700 results in the past year –

    “Record rain hits Australian grain harvests | Earth Times News
    Dec 6, 2010 … Sydney – Record rainfall in Australia has seriously damaged the crop that farmers hoped would … Flooding kills three in southern Spain …”

    “BBC News – Landslides kill 36 in Guatemala
    Sep 5, 2010 – Record rainfall. Weeks of heavy rain have saturated Guatemala’s mountainous terrain…”

    “National flooding Articles, National flooding News – …
    Nov 8, 2010 – Floods devastate West and Central Africa killing 397 ”

    “Typhoon Morakot dumps record rains on Taiwan; causes more flooding …
    Aug 19, 2010 – … record rainfall, landslides, and flood-related destruction on Taiwan. ”

    “BBC News – China flood fears along North Korea border
    Aug 6, 2010 – China has suspended traffic on the Yalu river, which marks the border with North Korea, because of record rainfall in an area already badly hit by floods. …”

    “State of the Climate | Global Hazards | May 2010
    Jun 9, 2010 – A slow-moving severe storm system brought record rainfall and flooding and spawned several … Flooding in South China from servere stroms on 10 May 2010 …”

    “Flooding in RI videos: Record rainfall totals in Rhode Island …
    Mar 30, 2010 – Rhode Island Precipitation Map School closings in RI Parts of RI and Mass. are underwater. Hardest hit are Cranston, West Warwick, Warwick and Providence.”

    “Nashville Flooding from Record Rainfall | Digital News Report
    May 3, 2010 – Nashville Flooding from Record Rainfall. May 3rd, 2010. Digital News Report – Downtown Nashville has been flooded after receiving record amounts of rain, …”

    “Record rainfall pounds drought-stricken region – Morning Call
    Sep 30, 2010 – After a hot dry summer that led to a drought watch, skies opened Thursday with a vengeance, leading to flooded roads, a truck rescue, a tornado watch and ……”

    “Record rainfall sees worst floods since 1940s | Olive Press …
    Dec 24, 2009 – Some of heaviest rain on record leads to flood chaos in Andalucia. Here, a submerged house in Jimera de Libar, near Ronda. Picture Karl Smallman.”

    “Record rainfall on Thursday caps a wet week in region …
    Oct 1, 2010 – Record rainfall on Thursday caps a wet week in region … There was minor flooding in parts of Blackwater, Sandbridge and Muddy Creek roads from south winds …”

    “Press Release: Red Cross Helping Those in Need Following Record …
    Sep 28, 2010 – Red Cross Helping Those in Need Following Record Rainfall and Widespread Flooding in Southern Minnesota. ”

    “1 drowning confirmed in flooding after record rainfall in Oklahoma …
    Jun 15, 2010 – Record-busting rainfall and ensuing flooding in Oklahoma led to at least one death,”

    “Record rainfall raises concerns over another spring flood | WDAY …
    Oct 26, 2010 – Flooding concerns. The record rainfall Tuesday is leaving Fargo city leaders concerned about another spring flood; the third in a row. “

  9. 209

    WJ 200,

    CO2 does not “replace” water vapor in the atmosphere. As CO2 increases, and warms the planet, H2O also increases. Google “Clausius-Clapeyron relation.”

  10. 210
    John E. Pearson says:

    J: 205 says the MET office made a prediction for the 2010 mean global temperature with 4 significant figures.

    Here’s my prediction for J; you are a liar. I bet you $100 that you cannot produce any official MET publication in which they predict next year’s globally and time averaged surface temperature to four significant figures with no error bars. Lemme know how that works out for ya.

  11. 211
    Rod B says:

    Walter Pearce (197), federal payroll taxes go 100% to Social Security and Medicare. Since your carbon tax would reduce payroll taxes, I was wondering if the collected carbon tax would also be dedicated to SS and Medicare. It’s a simple question.

    You ‘Say something intelligent on the subject of how to incorporate carbon’s externalities into a free market system.’

  12. 212
    Rod B says:

    Wayne Justice, I don’t think it alters your point (which I am neither supporting nor refuting here) but, ignoring insignificant effects like doppler, CO2 re-radiates at the same IR frequency that it absorbs.

  13. 213
    Walter Pearce says:

    #211 “a simple question…”

    Rod B. and his adjectives…In reality, those payroll taxes do not currently go to Social Security and Medicare, as you’re surely aware — remember those file cabinets in West Virginia?

    The more important issue — where it would be refreshing if not astonishing to hear something cogent and relevant from you — is at the other end, where the tax is paid. You keep resisting ideas on reducing carbon’s footprint, including subsidies as for hybrid vehicles. I’m not a fan of subsidies myself. So I offered Paul Hawken’s carbon tax idea as a revenue-neutral, free market approach to incorporating carbon externalities into product costs.

    Shock the world with an intelligent, on-topic response. How would you incorporate a truer picture of carbon’s costs?

  14. 214
  15. 215
    Pete W says:

    @214 JCH

    Thank you for that metoffice link. This seems to be another case of taking a prediction and blowing it out of proportion. The metoffice release said “A record warm year in 2010 is not a certainty…” but some are presenting it to others as if it was supposed to be a certainty.


  16. 216
    Hank Roberts says:

    > four significant figures
    I think he meant “2, 0, 1, 0”

  17. 217
    borninoz says:

    @215 Pete W

    I don’t think it’s a case of a prediction being blown out of proportion … the MET office did publish it, so asking how it’s going seems fair.

    As far as how it’s going, they predicted an anomaly of 0.58C, and through October, the anomaly was 0.52C, so to answer 205 J, it seems to me it’s going pretty well. Thanks for asking.

  18. 218
    JCH says:

    Thanks Pete W.

    Is that really a prediction?

  19. 219

    #214 et seq, especially #218–Well, define “prediction.” The actually Met Office verbiage is “expected to be 14.58 C.”

    To me, that would be a “prediction,” but one admitting of (unquantified) uncertainty.

    For context, the mean for the baseline period is 14.0, and the existing record (Hadcrut, since this is the UK we’re talking about) is 1998, at 14.52 C.

    “How’s it going?”

    Well, we’re about 11/12ths of the way to actually knowing the result, so I’d say it’s going well, too.


  20. 220
    Dan H. says:

    It looks like any prediction of the warmest year on record is going to fall short of 1998, trailing by almost 0.1C through October. 2010 is also only 0.01C above 2002 and 2005 for the first 10 months, so is likely to end the year somewhere between 2nd and 5th overall.
    The prdiction was based on the developing El Nino, which turned out to be rather accurate. During the summer, the El Nino faded to a La Nina which is taking on a rather strong signature, and led to decreased temperatures starting in Septemeber, and is likely to continue in the coming months. The Met office issued a statement that this winter was going to be as mild as last winter. lol.

  21. 221
    Dan H. says:

    Of course, the weather-related deaths this year pale in comparison to past years. There will always be weather-related deaths, but they should be put into perspective. The number of weather-related deaths pales in comparison to other causes.

  22. 222
    flxible says:

    …. decreased temperatures starting in Septemeber, and … likely to continue in the coming months.

    Wow! Who would have ever expected that?? Lower temperatures in the winter!!

  23. 223
    JCH says:

    “Preliminary operational data from 1-25 November indicate that global temperatures from November 2010 are similar to those observed in November 2005, indicating that global temperatures for 2010 are continuing to track near record levels. …” –

    HadCRUT underestimation?

  24. 224
    Maya says:

    Dan: It looks like any prediction of the warmest year on record is going to fall short of 1998, trailing by almost 0.1C through October.


    “For January–October 2010, the global combined land and ocean surface temperature was 0.63°C (1.13°F) above the 20th century average of 14.1°C (57.4°F) and tied with 1998 as the warmest January–October period on record.”

    Sources, Dan, cite your sources. Actual data, not media stories. We’re going to keep asking you to do that, you know.

  25. 225

    #221–“Of course, the weather-related deaths this year pale in comparison to past years.”

    Oh, yeah? According to whom? We had heatwaves that may have killed over 17,000 this summer, as well as devasting floods that killed over 2,000 in Asia. There was considerable hurricane-related mortality in the Caribbean. There was widespread drought and famine, especially in the Sahel, affecting millions. Hard to know what the mortality was there.

    It seems fairly jejune to have to mention that, in addition, conclusion on 2010 are a little premature with nearly another month to go.

    So, why and how was this year “of course” so much better than other years, chez vous?

  26. 226
    Dan H. says:

    From CRU, Jan-Oct 2010 was 0.499 above the 1961-1990 average, while Jan-Oct 1998 was 0.575 above the average. Ten-month anomalies for 2002 and 2005 were .485 and .492 respectively. Data, not media.
    Flxible, you are one funny dude. Maybe you should become a climate comedian.

  27. 227
    Maya says:

    Dan, now see, was that so hard? The annual value for 1998 only ends up being 0.548, so we shall see where we finish. 0.1C lower looks unlikely.

    I think the actual recent prediction (at least, the ones I saw) was that it would end up being just behind 1998, and it is on track to do that.

  28. 228

    Dan, so “any prediction of the warmest year” means “the HADCRUT warmest year only?”

  29. 229
    Brian Dodge says:

    “Of course, the weather-related deaths this year pale in comparison to past years. There will always be weather-related deaths, but they should be put into perspective.”
    Dan H. — 7 December 2010 @ 11:53 AM
    I’m sure that is of great comfort to the survivors of those few who died in weather related events – despite modern improvements in forecasting, emergency response, medical care, and international assistance.

    “Increased extremes of summer dryness and winter wetness are projected for much of the globe, meaning a generally greater risk of droughts and floods. ,This has already been observed, and is projected to continue. In a warmer world, precipitation tends to be concentrated into heavier events, with longer dry periods in between.”
    “The amount of rain falling in the heaviest downpours has increased approximately 20 percent on average in the past century, and this trend is very likely to continue, with the largest increases in the wettest places.”

    Care to venture a guess as to how many fewer deaths would have occurred absent AGW?

    “In spring 2008, heavy rains caused the Mississippi River to rise to about 7 feet above flood stage, inundating hundreds of thousands of acres of cropland. The flood hit just as farmers were preparing to harvest wheat and plant corn, soybeans, and cotton. Preliminary estimates of agricultural losses are around $8 billion. Some farmers were put out of business and others will be recovering for years to come.” [ibid]

    “Losses caused by catastrophes, defined as greater than $5 million, have grown steadily in the United States, from about $100 million annually in the 1950s to $6 billion per year in the 1990s. The annual number of catastrophes grew from 10 per year in the 1950s to 35 per year in the 1990s”

    What are your out of pocket weather related expenses? Were you bankrupted by extreme weather? Do you think that the costs are equitably distributed, or too small to worry about?

  30. 230
    Susan Anderson says:

    Weather related deaths:

    Have you forgotten Pakistan and Moscow, as well as the second wave in Haiti, so soon. How about Venezuela and Bolivia, Vietnam and China (I’m sure this list is seriously incomplete, but these all had catastrophes.

    Yeah, I know, “no single weather event”. But if this is not a trend, what is?

  31. 231
    Brian Dodge says:

    “Yeah, I know, “no single weather event”. But if this is not a trend, what is?”
    Comment by Susan Anderson — 7 December 2010 @ 9:30 PM

    Once is happenstance. Twice is coincidence. Three times is enemy action. More than 15 times in the past year is climate change. &;>)

    It’s comparable to the trends in record high temperatures – No doubt the crew at wattsupwiththat think it’s all due to the uncorrected urban wet island effect and bad siting of rain gages.

  32. 232
    CM says:

    A warning to all weather-data obsessives (you know who you are):

  33. 233

    “No doubt the crew at wattsupwiththat think it’s all due to the uncorrected urban wet island effect and bad siting of rain gages.”

    Probably. But what a better world it might be if they’d just correct the siting of their tinfoil hats.

  34. 234
    Dan H. says:

    Do you all have such short memories that only the most recent year is relevant? In the past decade, droughts have been a relative non-occurrance compared to early in the 20th century (See link above), or the fatalistic 18th and 19th centuries. The trend in tropical cyclones is downward, with 2010 being the lowest in over 30 years!

    More record high temperatures in the U.S. were set in the 1930s or 1950s than this past decade, and your dollar figures should really be inflation-adjusted to get any true meaning. Since prices rose ~400% from the mid 50s to the mid 90s, one would expect 50 events per year, so the data is actually a decrease in catastrophes.
    Pakistan experiences this type of flooding every 20-25 years, so this is not that much of an anomaly. This year’s event was very similar to 1973.

    Is the Russian heat wave a sign of global warming? No. Is the current European freeze a sign of a new mini ice age? No. These are all weather events that have a realistic chance of occurring, and do occur repeatedly over time. And Brian, I would venture to guess that weather-related deaths would be much higher absent AGW, as extreme cold is one of the most potent weather-related killers.

  35. 235
    Maya says:

    “The trend in tropical cyclones is downward, with 2010 being the lowest in over 30 years!”

    Adding Atlantic storms to the count… If you look here:

    Scroll down to the named storms chart for the Atlantic basin, from 1851 to 2009. It doesn’t include 2010, but what I want to bring to your attention is that the long-term average is a little over 11. Since 1995, 11 of them have been above-average. For 2010, we’ve had 19: so that brings the count to 12 of 15 above average.

  36. 236
    Maya says:

    Sorry, 12 of 16, including 2010.

  37. 237

    #233 Dan H.

    You venture to guess quite a bit me thinks. Should we really trust your guesses?

    – More high temps 30’s to 50’s: Think global not local.

    – catastrophes? What about this:

    As to weather events: One thing that is reasonably clear is that these weather events are occurring while the radiative forcing is above the relatively stable thermal equilibrium. SO you certainly can’t rule out the potential influence and it is not unreasonably to say that there could be some climate change related influence.

    I will not be surprised as future studies begin to refine and identify the mechanisms associated to the trend shifts.

    Will you?

    It is important to understand that climate actually does affect weather. Direct attribution to single events may be a little harder to pinpoint, but you can’t say “No.” by a long shot.

    Or said another way, your characterization is dead wrong by all reasonable accounts.

    By the way, what European freeze? have you been reading informations on the internets again?

    It snowed a few days and now its raining. It’s not freezing, it’s wet. In fact it’s so wet, I don’t want to go to the store and I am out of bananas. Sure, it’s a bit chilly up in Norse country, but why the dramatic phrasing ‘European Freeze’. You make is sound like we are all dying over here.

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  38. 238

    #234 Dan H.

    Re. “weather-related deaths”

    Bringing up anything that even remotely sounds like a Bjorn Lomborg argument merely reveals a near total lack of incompetence in understanding relevance, or motive drivers at source for that matter.

    But what the heck. Okay Dan H. the anonymous wonder please to impress us with the peer reviewed study you dug that canard up out of. Yeah, I know that’s a contradiction in premise, sort of. But, just in case the canard did make it into a journal review, I’d still like to see it.

  39. 239

    oops, my bad.

    “total lack of incompetence”

    should read

    ‘total lack of competence’

    Don’t I look silly now ;)

    hmmm…, better head this one off at the pass. Before you attack me for being incompetent, be aware that I am in certain areas. Such as posting on blogs while answering silly statements from people that prefer to guess, and represent their guesses as facts; as opposed to actually doing the research and finding the relevant data.

    Yeah, I should watch my double negatives ;)

  40. 240

    Funny, perhaps the most comprehensive recent review of the question of drought paints quite a different picture:

    Perhaps that’s because Dan’s source is not an actual research paper, but rather a publication (I choose a neutral term here!) from a political organization:

    CSCCC claims it was established as a direct response to “the many biased and alarmist claims about human induced climate change, which are being used to justify calls for intervention and regulation.”

    Internally to that document, I note that 1) the paper does not consider the actual occurrence of droughts and other disasters, but rather deaths due to them, and 2) the recent data are simply not credible, probably due to a “creative” choice of definitions.

    To the first point, since human ability to predict and/or respond to disasters of all types has improved massively over the last century, considering mortality per se doesn’t say anything at all about the trends of occurrence of those disasters. So, if Dan’s “comparison to past years” means the early years of the 20th century, then I suppose he was technically correct–but I don’t agree that that it’s meaningful. As Dan’s source itself says:

    . . .society’s ability to cope with extreme events has not only improved, it has also put its increased adaptive capacity to good effect.

    To the second point, the article claims that between 1990 and 2006, all of 186 people died as a result of drought. That’s according to the database Em-Dat. I tried to rerun the search for 1990-2006 just for Africa, but for some reason had no luck; the software kept claiming no result at all. But running a search for Africa alone since 2000 resulted in reports of 1197 deaths due to drought, with most countries–including some (notably Chad) known to have been among the most severely drought-stricken reporting *zero* fatalities. With all respect to the good folks at Em-Dat, this is not credible as a complete estimate.

    (That’s not to say the exercise is without value, of course.) The link for EmDat:

    Oh–running the search for worldwide drought fatalities from 1990-2006 resulted in 4464 reported fatalites–none in Eritrea, Sudan, or Chad, interestingly. Som-alia did report 23.

    Why the discrepancies? Well, the csccp report did their search in 2007 (hence 2006 as the then-latest year); quite possibly more reports have come in since. (But clearly, many places just don’t report, period.)

    Taking Chad as an example, actual mortality numbers aren’t super easy to find. The impression that I get is that the situation just doesn’t allow considering mortality on a “retail” basis. Rather, you get statements like this:

    The EFSA said the drought was largely responsible for pushing already alarming rates of child mortality in Chad up by 15 percent, from 2.0/10,000 in March 2009 to 2.3/10,000 today.

    That’s from here:

    Or this:

    It is a severe and large-scale crisis comprising malnutrition, food insecurity and other effects of drought which will require life-saving aid for an additional 1.6 million people. The crisis affects the Sahel belt, specifically in Kanem, Bahr El Gazal, Guera and Batha regions in western and central Chad. A total of 50,000 children are suffering from severe acute malnutrition (SAM). This is half of the nationwide total of 102,000 children suffering from SAM.

    (Call me cynical, call me simple-minded, but I strongly suspect that not all of 102,000 children suffering from severe acute malnutrition are going to survive–or have survived.)

    From here:$FILE/myr_2010_Chad.doc?OpenElement

    (That one downloads a Word Document, so don’t click if that’s not what you want to happen.)

    Lastly, part of the problem of the discrepant numbers takes us to the second of my points above: the definitional problem. The csccp report makes the claim–confidently repeated by Dan, as by so many denialists before–that cold is ever so much more lethal than heat. That claim, though, is sustained mainly by this choice:

    The Center for Disease Control’s WONDER database was used for extreme heat and cold, because it is based on actual death certificate records, which, in turn, are based on medical opinion as opposed to the National Weather Service’s expert opinion.

    “Medical opinion” means “based upon death certificates.” But medical examiners are properly conservative in their conclusions, so if a person dies of heart failure during an episode of heat stress, it’s quite likely that the inference necessary to find the death due to heat stress will not be drawn, or at least not on the death certificate. That, after all, would require “expert opinion.”

    And studies choosing to use the NWS “expert opinion” data reach quite different conclusions–so it’s quite possible that heat is in fact more lethal, on average, than cold. I don’t think it’s presently appropriate to state airily as fact that one or the other possibility “is true.”

    Similarly the drought issue. How do you separate the malnutrition from the acute infectious disease from the poverty from the drought–or, for that matter, from the military conflict and political chaos? It’s not easy to do–the unconvincing propaganda from the csccc notwithstanding.

    (Yeah, I know–I let the neutral terminology go there, didn’t I? That’s because this business royally ticks me off. It’s not bad enough that all this stuff is happening, but certain people and institutions actually have the infernal gall to blatantly misrepresent it, sweeping the IN-human reality under a carefully-sanitized rug.)

  41. 241
    Brian Dodge says:

    “More record high temperatures in the U.S. were set in the 1930s or 1950s than this past decade,…”

    According to the graph on page 20 of “SURFACE TEMPERATURE RECORDS: POLICY-DRIVEN DECEPTION?” by Joseph D’Aleo and Anthony Watts SPPI ORIGINAL PAPER ♦ UPDATED: Aug. 27, 2010, there were more than 2500 weather stations reporting in the 30s, more than 3500 in the 50s, and less than 2000 by 2010; were those “more record high temperatures” adjusted for the deflation in stations by whoever was trying to spin the data you were given?
    I downloaded the record high temperatures for all of January 2009 from using the custom date generator and tabular data options. There were ~400 records; I then plotted temperature versus date of previous high temperature for that date and station – see – there isn’t any qualitative clustering of records in the 50s or 30s.
    The data spans 111 years to the earliest previous record; if record highs were randomly distributed over that period, the mean would be ~55 years to the previous record, with a stdev of ~33 years. The actual mean interval is ~27 years, std dev 22 years; in other words, record high temperatures are occurring more recently. Of these stations that had record highs in Jan 2009(a fixed, not declining number of stations), 104 had previous record high temperatures in the previous decade, 1998-2008; 24 had previous record highs 1950-1959; and only 5 had previous highs in the 1930s.

    “…and your dollar figures should really be inflation-adjusted to get any true meaning. Since prices rose ~400% from the mid 50s to the mid 90s, one would expect 50 events per year, so the data is actually a decrease in catastrophes.”

    Uh, when I adjust $6 billion loss/year in the 90’s for 400% inflation, I get $1,500 million versus $100 million annually in the 50’s, which is not “actually a decrease”.

    “…extreme cold is one of the most potent weather-related killers.” Move the goalposts much?
    according to “Summary of Natural Hazard Statistics for 2009 in the United States”[1] , extreme cold caused 33 fatalities, extreme heat caused 45 fatalities, and river floods + flash floods caused 53 fatalities. FWIW, extreme cold caused $0.09 million in property damage, and flooding(the hazard I originally discussed) caused $1.046 BILLION in property damage.
    When moving the goalposts, one should be careful not to score on oneself.

    [1] (NOAA website)

  42. 242
    Rod B says:

    John P. Reisman (OSS Foundation), I don’t think it’s fair to single out Dan H to uniquely use only global events in his arguments. Nobody on the other side of the debate does. Using weather events as validation of warming is by definition localized.

    … just sayin’ …

  43. 243
    Walter Pearce says:

    #242 “single out Dan H…”

    Who’s being singled out? Rod B., Dan H. and others all get opportunities to provide evidence for their statements. The criticism comes from their failure to do so and propensity to change the subject rather than admit to facts.

    Attempts to engage these people always degenerate into dialogs right out of Scary Movie 3. Rod B. = Mahalik…

    Mahalik: I heard Jamal from 90th street watched that tape last week and this mornin’ he woke up dead!
    CJ: How the h— do you wake up dead?
    Mahalik: Cause’ you’re alive when you go to sleep.
    CJ: So you’re telling me you can go to bed dead and wake up alive?
    Mahalik: You can’t go to bed dead! That s— would’ve been redundant.
    CJ: No it wouldn’t cause’ you can go to bed and not be dead, and you can die and not be in the bed.
    Mahalik: But you are in the bed. That’s how you wake up dead in the first place fool!
    CJ: Damn! that’s some quantum s— right there man! You should be teaching classes!

  44. 244

    #241–Yes. I think there is another effect, too, unless I’m not conceptualizing this correctly.

    But–the instrumental record begins in 1880 (loosely speaking.) Given a fixed beginning point, in the absence of a temperature trend one would expect the probability of new records to decline over time, as you continually need more and more “extreme” events in order to eclipse the previous record. In the 1930s, there were ca. 50 years of data (again, loosely speaking); now, there are obviously 70 years more in the books.

    That line of thought would lead me to expect a decline in numbers of records–unless, of course, climate is actually warming.

  45. 245
    Dan H. says:

    You guys are amazing.
    Brian, I am talking about record heat, and you counter with temperatures from January? We all know that the temperature increase in the latter 20th century was primarily due to increased winter and night-time readings. Check out the U.S. temperatures in July. Five of the ten hottest summers occurred in the 1930s. When was the last time the mercury exceeded 120F in North Dakota?
    You should also read your article more carefully, as the following was given as the cause of the increased dollar losses due to weather:
    “The scientists report that most of the increase has been due to societal shifts. The growth of population, demographic shifts to more storm-prone locations, the growth of wealth have collectively made the nation more vulnerable to climate extremes.” I think you just put one through your own post.
    I presented data about the long-term global tropical cylcone strength, and you try to refute the data with the number of Atlantic tropical storms in 2010? That is like bringing a knife to a gunfight.
    Your report on droughts shows several aspects on drought which you may have overlooked.
    1. North America experienced several droughts similar in severity to those in the 1930s and 1950s, but longer in duration (20-40 years) between 1100 and 1400 a.d.
    2. The worst droughts in China occurred in the 1640s, 1580s, and 1960s, and widespreads drought occurring from 1500-1730 and since 1900.
    3. The devasting drought in the Sahel region of Africa during the 1970s and 1980s is not unusual, having occurred several times in the past millenia.
    4. Their data shows a drought index increase since the 1950s. However, their data also shows that the 1950s were a particularly wet time in history, and that when earlier data is included, recent years do not stand out as being particulary dry.
    You do raise a good question about how drought-related fatalities are distinguished from malnutrition. I would also add those due to wars disrupting food supplies, such as experienced in Sudan.
    I agree. Using local weather events to show that global warming is (not) happening is poor support for ones argument. If you have 100 reporting stations, then 100-year events would statistically occur annually.

  46. 246

    Dan H: 1. North America experienced several droughts similar in severity to those in the 1930s and 1950s, but longer in duration (20-40 years) between 1100 and 1400 a.d.

    BPL: At the time, 800 million people didn’t depend on harvests from that land.

  47. 247

    DH: 4. Their data shows a drought index increase since the 1950s. However, their data also shows that the 1950s were a particularly wet time in history, and that when earlier data is included, recent years do not stand out as being particulary dry.

    BPL: In 1870, 6% of Earth’s land surface was in “severe drought” (PDSI .le. -3). In 1970 it was 12%. In 2003 it was 31%, in 2005, 21%. It’s a very variable series, but the trend is very clearly up for the past 140 years.

  48. 248
    Dan H. says:

    What is interesting in their data, is that the precipitation component of the PDSI is currently near the 60-year average. The highest value (28%) was recorder in 2003, and the lowest values (11%) in 1979 and 2007. It was 22% in 1950. Overall, no trend in precipitation has been observed.
    The temperature component of PDSI results in much higher values recently due to the observed warming.
    The top-1mm soil moisture content, after rising at the turn of the century, have fallen to near average.

  49. 249
    Maya says:


    Accumulated cyclone energy (ACE) is a measure used by the National Oceanic and Atmospheric Administration (NOAA) to express the activity of individual tropical cyclones and entire tropical cyclone seasons, *particularly the North Atlantic hurricane season.* ( – emphasis mine) I wasn’t trying to refute anything, merely adding information. I think it’s very interesting that the Atlantic ACE is still well above average (40% – ) even though the global ACE is apparently low. Don’t you?

    Most everything else I can find on ACE is regarding the North Atlantic hurricane seasons. If you google “global accumulated cyclone energy” you end up at Maue’s page, or a page that references Maue’s page. For that reason alone I am skeptical of putting too much weight on it. Why isn’t the NOAA/NCDC analyzing it, too?

    This paper, for instance, talks about the trend in increasing tropical cyclone intensity, but points out the dearth of reliable data before the 1970s.

  50. 250
    Dan H. says:

    The ACE shown by the NOAA dating to 1840 shows a pseudo-cyclical trend, with no net long-term change. 30 years ago, Atlantic hurricane activity was much lower than recently; 60 years ago, it was similar; 90 years ago it was lower again; 120 years ago it was high again; 150 years ago it was low. The cycle appears to closely follow the AMO.
    Also, the Atlantic hurricane season increases in intensity during La Ninas, while the Pacific typhoon activity increases during El Ninos. The idea that the two ocean bases show opposite activity is not all that surprising. Since cyclonic activity is typically higher in the Pacific, it makes sense that global activity would generally follow the strength of the Pacific Typhoons. I am not sure about Indian Ocean cyclones, but I thought they followed El Ninos also.