Global Cooling-Wanna Bet?
By Stefan Rahmstorf, Michael Mann, Ray Bradley, William Connolley, David Archer, and Caspar Ammann
Global cooling appears to be the “flavour of the month”. First, a rather misguided media discussion erupted on whether global warming had stopped, based on the observed temperatures of the past 8 years or so (see our post). Now, an entirely new discussion is capturing the imagination, based on a group of scientists from Germany predicting a pause in global warming last week in the journal Nature (Keenlyside et al. 2008).
Specifically, they make two forecasts for global temperature, as discussed in the last paragraphs of their paper and shown in their Figure 4 (see below). The first forecast concerns the time interval 2000-2010, while the second concerns the interval 2005-2015 (*). For these two 10-year averages, the authors make the following prediction:
“… the initialised prediction indicates a slight cooling relative to 1994-2004 conditions”
Their graph shows this: temperatures in the two forecast intervals (green points shown at 2005 and 2010) are almost the same and are both lower than observed in 1994-2004 (the end of the red line in their graph).
Figure 4 from Keenlyside et al '08
The authors also make regional predictions, but naturally it was this global prediction that captivated most newspaper stories around the world (e.g. BBC News, Reuters, Bloomberg and so on), because of its seeming contradiction with global warming. The authors emphasise this aspect in their own media release, which was titled: Will Global Warming Take a Short Break?
That this cooling would just be a temporary blip and would change nothing about global warming goes without saying and has been amply discussed elsewhere (e.g. here). But another question has been rarely discussed: will this forecast turn out to be correct?
We think not – and we are prepared to bet serious money on this. We have double-checked with the authors: they say they really mean this as a serious forecast, not just as a methodological experiment. If the authors of the paper really believe that their forecast has a greater than 50% chance of being correct, then they should accept our offer of a bet; it should be easy money for them. If they do not accept our bet, then we must question how much faith they really have in their own forecast.
The bet we propose is very simple and concerns the specific global prediction in their Nature article. If the average temperature 2000-2010 (their first forecast) really turns out to be lower or equal to the average temperature 1994-2004 (*), we will pay them € 2500. If it turns out to be warmer, they pay us € 2500. This bet will be decided by the end of 2010. We offer the same for their second forecast: If 2005-2015 (*) turns out to be colder or equal compared to 1994-2004 (*), we will pay them € 2500 – if it turns out to be warmer, they pay us the same. The basis for the temperature comparison will be the HadCRUT3 global mean surface temperature data set used by the authors in their paper.
To be fair, the bet needs an escape clause in case a big volcano erupts or a big meteorite hits the Earth and causes cooling below the 1994-2004 level. In this eventuality, the forecast of Keenlyside et al. could not be verified any more, and the bet is off.
The bet would also need a neutral arbiter – we propose, for example, the director of the Hadley Centre, home of the data used by Keenlyside et al., or a committee of neutral colleagues. This neutral arbiter would also decide whether a volcano or meteorite impact event is large enough as to make the bet obsolete.
We will discuss the scientific reasons for our assessment here another time – first we want to hear from Keenlyside et al. whether they accept our bet. Our friendly challenge is out – we hope they will accept it in good sportsmanship.
(*) We adopt here the definition of the 10-year intervals as in their paper, which is from 1 November of the first year to 31 October of the last year. I.e.: 2000-2010 means means 1 November 2000 until 31 October 2010.
Update: We have now published part 2 of this bet with our scientific arguments.
_______________________
Update: Andy Revkin has weighed in at "dot earth".
Update 5/11/08: so has Anna Barnett at Nature's 'climate feedback' blog
8 May 2008 at 2:09 PM
“Now, an entirely new discussion is capturing the imagination, based on a group of scientists from Germany predicting a pause in global warming last week”
Just to clarify, thy do not really predict that global warming will take a pause now, they predict it will continue to take a pause until 2015.
We have a 0 trend for almost 11 years now so adding up another 6 years with no increase would result in 17 years with no increased temperature, just to clarify.
Predicting the climate seems to be like betting on horses, there are alot of experts who know which horse that will win, but very few that actually get rich from betting on them.
8 May 2008 at 2:12 PM
This doesn’t look to be a fair bet to me.
8 May 2008 at 2:14 PM
They’d be suckers to take your bet, especially the first part. The Nov.1994 - Oct.2004 average for HadCRUT3v is 0.3594, the average from Nov.2000 to the present is 0.4246. This means that for them to win the 2000-2010 part, the average temperature from now to Oct.2010 would have to drop to 0.1722. ‘Tain’t likely.
[Response: Congratulations, it took you just 15 minutes to work this out. Of course they know those data too, and they still went into Nature and to the media with this forecast. They must have good reasons. If they do, they will take our bet. -stefan]
8 May 2008 at 2:25 PM
Anything to move on from just rolling the dice.
8 May 2008 at 2:44 PM
I hope the authors take the bet! I want in, too — I could use the money! Enjoy the 5000 Euro coming your way.
8 May 2008 at 3:02 PM
I am not a scientist nor a sceptic. But i have often wondered if there was a variation or reversal of trend, by what mechanism would the heat escape? Does not the theory of GW envision a steady temerature rise? Or do variations represent data errors that mask the median trend?
[Response: There are many mechanisms for natural short-term cooling. Some are of course external– large volcanic eruptions block incoming solar radiation from reaching and being absorved by Earth’s surface. But some are internal. ENSO events, for example, can warm or cool ocean surface temperatures through exchange of heat between the surface and the reservoir stored beneath the oceanic mixed layer, and by changing the distribution and extent of cloud cover (which influences the radiative balance in the lower atmosphere). -mike]
8 May 2008 at 3:03 PM
It is interesting that if the authors are right, than global warming should go up (in fairly large) steps, rather than linearly, since the paper does not have implications for climate sensitivity. Still, given that the last decade has not seen a significant amount of warming (although any trend is swamped by noise), 20 years of little warming would give skeptics a little wiggle room. Some others such as Gavin and Tamino (and myself) have said that if there is no warming by 2015 (perhaps 2020) then there may be something quite wrong in our understanding. Personally, I’d bet on the RC side being right here.
8 May 2008 at 3:14 PM
Could explain why you have little confidence in their report?
I respect this site a lot, but this kind of gaming seems a bit silly without a formal explanation about why you think the model is weak.
[Response: I missed the part where we implied their model is weak. We do have some issues with the experimental design and interpretation, and as we indicated in the post we will discuss those in due course. -mike]
8 May 2008 at 3:20 PM
The bet itself sounds like a good experiment, if slightly Victorian.
Anyway, I suggest using the Long Bets website, it provides a good neutral clearinghouse for such things. They will also do the third-party verification and contact the necessary experts (for instance, in the event that a specific one chosen passes away prior to the completion of the bet).
8 May 2008 at 3:31 PM
I think these guys have been watching too many TH r-e-k-o-p tournaments on TV. They believe they have a good read on Mother Nature, are holding the abs nuts and have decide to go all-in. Good luck guys!
8 May 2008 at 3:35 PM
Isnt this paper all a bit of a storm in a teacup? From their graph that you show, if you run a line through the 1995 values and the 2025 values the slope is still steeper than the pre 1995 values.
If they have identified a sink (increased fragmentation and hence increased surface area of ice sheets, mayhap?) that initiated stronger dT uptake C1995 and which will be saturated (gulp - ?melted?) C2010 when their green line kicks up to a much faster dT per year than A1B then so what? Well found – what is the sink? More understanding is good.
But by 2025 they arrive at the same answer as A1B but go through 2025 at a much higher rate of dT per year. Please ask them about that!
8 May 2008 at 3:46 PM
OK, I’m a layperson, albeit one with an intense interest in the subject at hand. So please don’t throw too many rocks when I ask:
When we’re talking about “warming”, what exactly is warming? The air? The oceans? Ice that’s no longer part of glaciers or Arctic sea ice but is now water? (The graph reproduced above is labeled “global mean surface temperature”, which sounds to my untrained ear like air temperatures.)
My point is that I could easily see how the entire system in question could be warming, but because of transient effects, like weather patterns, the additional heat energy could easily wind up not where we’re measuring it for months or even years at a time. (I’ve been particularly interested in the Arctic sea ice situation the last few years. How many calories does it take to melt such vast amounts of ice? And how much apparent cooling could that cause if we’re measuring just air temps?)
I’m far less concerned with where the heat energy is in the short run than the fact that the overall amount continues to increase.
8 May 2008 at 3:51 PM
Minor(I think) nitpick. The end of the red line in the graph appears to end in about 1998, not 2004.
[Response: This is all about 10-year averages - see footnote at bottom of article. They are centered on the graph. Hence the point that represents the 1994-2004 average is plotted at 1999. -stefan]
8 May 2008 at 3:54 PM
“Naja, um Wetten geht hier wohl nicht, sondern um Wissenschaft. So geht das nicht, da ist ernstzunehmende Wissenschaft gefragt. Das sind nicht die üblichen deutschen Klimaleugner und sie leugen ja auch nichts, bestenfalls verschieben sie das Szenario um lächerliche 10 Jahre. Wetten braucht man da nicht, das ist doch kein Kindergarten”
Right, this should be not be be about betting on horses. This is all about serious science. These scientists are not denialists, they just postpone climate change in some regions for approx. 10 years. This is not a forum for betting on horses, it is a science forum”
8 May 2008 at 4:08 PM
What is your level of confidence in the prediction made by GISS: “barring the unlikely event of a large volcanic eruption, a record global temperature clearly exceeding that of 2005 can be expected within the next 2-3 years.”
http://data.giss.nasa.gov/gistemp/2007/
Does this prediction and the confidence with which it is made “The quasi-regularity of some natural climate forcing mechanisms, combined with knowledge of human-made forcings, allows projection of near-term global temperature trends with reasonably high confidence”, reflect the consensus of climate scientists, in your opinion?
8 May 2008 at 4:10 PM
@11
Yes, the paper is a storm in the teacup but over here in Germany it was was not fully understood, because it does not question the basic theory of cliamte change. I think it is just another model. But their theory cannot be easily dismissed. It is a quality piece of paper (good points, bad points), but I think realclimate was a little premature to answer it. However, the theory of cliamte change remains consistent.
8 May 2008 at 4:21 PM
Minor(I think) nitpick. The end of the red line in the graph appears to end in about 1998, not 2004.
i think the graph is smoothed (no 1998 spike….) and the endpoint is calculated from data between 94 and 04. but just a guess…
thanks for addressing this topic.
when discussing this topics sceptics tend to present the “Easterbrook projection” that turns out to be a wild guess:
http://gsa.confex.com/gsa/responses/2007AM/281.doc
(warning, word document..)
8 May 2008 at 4:39 PM
Re: #12 Lou -
There is a nice fresh video of Jonathan Overpeck of Univ of Arizona speaking of Western US changes, but imparts global understanding in explaining it.
Speaking here at the University of Washington - produced in April. Very current, very clear.
http://www.uwtv.org/programs/displayevent.aspx?rID=23654&fID=5126
“Climate Change, Sea Level, and Western Drought: Dangerous Anthropogenic Interference
Learn why the American West could be in trouble with surface air temperatures rising faster than elsewhere in the coterminous United States. Dr. Jonathan Overpeck, director of the Institute for the Study of Planet Earth at the University of Arizona, and recipient of the shared 2007 Nobel Peace Prize for his role as a Coordinating Lead Author for the UN Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment, will address the trend of droughts in the west and the vulnerability of coastal communities as they face sea level rise coupled with increasing storm intensities. This program is presented by JISAO, which fosters research collaboration between the University of Washington and the National Oceanographic and Atmospheric Administration.”
http://www.uwtv.org/programs/displayevent.aspx?rID=23654&fID=5126
8 May 2008 at 4:39 PM
Isn’t it odd that their so-called “verification” period indicates no global warming between 1985-1998? Since that is hugely incorrect, are we to conclude that their model is not very predictive? Or does “verification” mean something else in this context?
8 May 2008 at 4:43 PM
What about the eruption of Chaiten vulcano in Chile, is it suficiently important to affect the climate?
8 May 2008 at 5:12 PM
Shame on RealClimate for turning a serious scientific subject into a bet. If these authors are wrong please use the scientific method - evidence, reasoning, and yes climate models (if predictions vary) to convince others.
Gareth Evans
8 May 2008 at 5:19 PM
“To be fair, the bet needs an escape clause in case a big volcano erupts”
There is currently a big volcano erupting.
[Response: In full: “…the bet needs an escape clause in case a big volcano erupts or a big meteorite hits the Earth and causes cooling below the 1994-2004 level.” You forgot the last part. Whether this volcano will do that remains to be seen. Btw. - did Pinatubo leave even a blip in the red curve above? Remember we are talking 10-year averages. -stefan]
8 May 2008 at 5:34 PM
Re #12: It’s air temperature that is being discussed. Melting large quantities of ice requires large amounts of energy, and this slows the rate at which temperature would rise with the same energy input but no melting, but it is not a major effect. Also higher rates of ocean water evaporation produce a similar effect. In combination these two could possibly produce a “measurable” decline in the rates of warming, but I suspect that it would be measurable only if there was an equivalent Earth without the greater melting and evaporation rates so that a comparison could be made.
There really should be more emphasis on the overall effects of energy added to the troposphere and the upper oceans. Average air temperature is an important indication of energy changes, but it doesn’t tell us everything.
E.g., Assuming that the Keenlyside paper turns out to be accurate, it would mean that energy would be transferred from the atmosphere to the oceans at a higher rate for a time and then a lower rate. For the first period we might seem to be better off, but there are significant negative effects with a warmer ocean system. One of them seems to be a reduction in dissolved oxygen. If this passes tipping points in large enough volumes, there could be additional collapses in marine life beyond what we directly produce with overfishing and pollution.
I’m not at all sure that the net effect would be positive during the predicted 10 year period.
The point is that as long as greenhouse gases are reducing the rate of radiation from the land oceans and lower atmosphere, there may be no distribution of the net energy increase that results in good news. Those who might think that a ten year pause in air temperature increases gives us extra time are not looking at the whole picture.
8 May 2008 at 5:57 PM
Lou Grinzo (12) — I am under the impression that HadCRUTv3 uses air temperatures on land and sea surface temperatures in the oceans to produce their global mean.
Ayelén (19) & C. W. Magee (20) — Impressive as it may appear, Caiten is not that much of a volcano nor produces that big an eruption. There is probably a volcano site which will give you an estimate of the current eruption’s VEI. I believe it will be on the smaller end of the scale.
8 May 2008 at 6:06 PM
The two 10-year intervals have 5 years in common: 2000-2004. Thus the bet is really whether 1994-1999 would be warmer or colder than 2005-2010.
Assuming (for lack of any reason to be biased in any direction) that 2008-2010 would average to about the same temps as already known 2006-2007, the RealClimate team stands to win.
8 May 2008 at 6:10 PM
#19
//”What about the eruption of Chaiten vulcano in Chile, is it suficiently important to affect the climate?”//
Not likely. Volcanic eruptions don’t necessarily need to cause significant cooling. You need to look at the sulfuric-acid particles (aerosols). The eruption of El Chichon for example was significantly less explosive than Mount St. Helens a couple years earlier, but the former caused a lot more cooling because it emitted far greater quantities of SO2 gas, whereas Mount St. Helens was largely fine ash that settled out.
#12 Lou:
In fact the troposphere heats and cools pretty uniformily as a unit, so the surface and atmosphere will all heat up, at least until you get up very high and enter the stratosphere. Land and oceans will heat up(most of the heat goes into the oceans), though land heats quicker because it has a lower heat capacity. Though keep in mind that different regions are affected by global warming. Some might not change much at all, while others are effected a lot more. Also keep in mind (as Gavin mentions) that there is a lot of short-term “noise” that will offset warming, or even cause cooling on short timescales (such as years to a decade or longer).
8 May 2008 at 6:23 PM
Re:#16 “i think the graph is smoothed (no 1998 spike….) and the endpoint is calculated from data between 94 and 04. but just a guess…”
Very good guess,Sod. The anomaly for 1998 is about 0.5 from the HadCrut3 graph. http://www.metoffice.gov.uk/research/hadleycentre/obsdata/HadCRUT3.html
Eyeballing the 1998 anomaly in their Figure 4 is about only 0.3. Thanks for helping to clear it up.
8 May 2008 at 6:50 PM
I must have missed a link to the full article along the way. I only see links to the abstract.
This is very sad that RC has been reduced to a carnival like betting on global warming.
8 May 2008 at 7:32 PM
Jim Cross, betting is a time honored technique for judging “degree of belief” or subjective probability. We place sufficient faith in it to determine prices for stocks and commodities. I don’t see the problem with doing a little applied Bayesian probability in climate science
8 May 2008 at 7:33 PM
Re: #19 by Ayelén: “What about the eruption of Chaiten vulcano in Chile, is it suficiently important to affect the climate?”
This is a spectacular, but not particularly big eruption at present.
http://icwales.icnetwork.co.uk/news/wales-news/2008/05/08/volcano-isolates-welsh-patagonia-91466-20877265/
“Experts are now waiting to see whether the volcano will affect the world’s climate.
“So far, Chaiten has emitted only a few thousand tons of sulphur dioxide.
“In general, a volcano must spew at least one million tons of sulphur dioxide into the stratosphere to have a global effect on climate.
“After eruptions of unusual size, sulphur dioxide, converted into sulphuric acid, can form a thin white cloud in the atmosphere that reflects sunlight away from Earth.
“The Philippines’ Mount Pinatubo produced a brief cooling of the climate after spewing 20 million tons of sulphur dioxide in 1991.”
[Response: Moreover, most of the climatically-relevant volcanic eruptions are the explosive tropical eruptions (El Chichon, Pinatubo, Agung, Tambora, Krakatoa, etc), because the general circulation of the stratosphere is such that the aerosols are transported poleward from the source latitude. So only tropical eruptions tend to blanket the global lower stratosphere, which is how you get a substantial global mean cooling. There are exceptions (e.g. the Laki eruption of 1783 in Iceland). Nonetheless, as Chaiten is located well outside the tropic, I wouldn’t expect much in the way of any global climate impact. And more specifically, I don’t see it being a deal-breaker for the bet in question. -mike]
8 May 2008 at 8:06 PM
Great idea, though I doubt Keenlyside et al. will be amused. If this were to grow into a larger betting pool I would be strongly inclined to bet with RC, in spite of the fact that this is so short term that it may be more like betting on weather than climate. Nearly every paper that I have seen recently that has indicated a meaningful change in rate for a variable related to warming has suggested that, if anything, average model sensitivity may be too low, with positive feedbacks underestimated. I agree with others that consider this a pretty bold forecast by Keenlyside et al. since I think that 2005-2007 were warmer than 1994-2004 requiring that 2008-2010 exhibit quite a steep cooling trend for their forecast to pan out.
8 May 2008 at 8:17 PM
Mike:
Given that there are generally only 0-3 VEI 6+ eruptions per century (Of which Chaiten might eventually become one, albeit at high latitude winter), why not just suck up the few % risk and drop the escape clause?
[Response: Call us risk averse if you like. -mike]
8 May 2008 at 8:21 PM
Having looked at their paper and their press release, I think the terms of your bet may be a little misplaced.
If you were living on a Keenlyside Earth and your global mean temperature followed their model, then you would still see warming, i.e. their model for 2000-2010 is warmer than their model for 1994-2004. So on the Keenlyside Earth the warming slows rather than stops.
This jives with their press release: “The improved predictions suggest that global warming will weaken slightly during the following 10 years.” Where I assume “weaken” is intended to mean “slow” rather than being a prediction of cooling. A more natural bet therefore might be to ask whether the real Earth warms faster or slower than the Keenlyside Earth.
In my opinion, it is only by willfully ignoring the misfit in their model at 1994-2004 that one would suggest that actual temperatures in 2005-2015 should be predicted to be colder than 1994-2004.
[Response: Robert, this is something we discussed with the authors before proposing the bet. The green points, despite being connected by a line, do not represent one model run. Rather, each green point is an individual forecast starting from somewhere near the red line. That is why in the paper they say they predict a slight cooling relative to 1994-2004. You are right that already their prediction (or better to call it hindcast) for the 1994-2004 period was too cold. Otherwise, if you compare the green and black curves from 1999-2010, their evolution is the same, they are simply offset. So if you just took the relative change since 1999, not the absolute numbers as compared to the red curve, their new model would predict the same warming as a standard scenario run (i.e. the black one), which would hardly have been a reason to go to the worldwide media with a “pause in warming” prediction. -stefan]
8 May 2008 at 8:21 PM
“I must have missed a link to the full article along the way. I only see links to the abstract. …” - Jim Cross@26
I believe this is the article:
http://www.usclivar.org/Pubs/2May08Keenlyside.pdf
8 May 2008 at 8:36 PM
I respect this site and its group of contributors greatly, but like Jim Cross I am disappointed to see this post as I think it trivialises the issues involved. Ray Ladbury, who I also respect, suggests that there no “problem with doing a little applied Bayesian probability in climate science” in this way. That would be fine to do in private with colleagues who understand the issues intimately, but this site attracts a lot of lay-people who come here for clear explanations of climate change science and informed debate on current topics. The take-away message from this post for a lay-person is that it is a game we are playing.
8 May 2008 at 8:40 PM
How pathetic. This bet is predicated on the assumption that the authors of the paper in question are “denier” sympathizers, placing them in an antagonistic position. Clearly what is at question is the science, not the scientists` beliefs. What kind of scientists would bet on their findings to add strength to their accuracy?
The people at Real Climate are behaving very childishly on this. Just address the science and leave punditry to punters. Please. Are you trying to bring the level of discussion down to that of Fox News? Do you justify your actions by playground slogans like “he started it”?
[Response: We are absolutely not proposing this on the assumption that the authors are “denier sympathizers”. The authors are very good and respected colleagues, and this post is entirely about the ability to predict natural climate variability a decade ahead. It is not about anthropogenic warming, a topic on which we completely agree with Keenlyside et al. The short time scale of this prediction makes it amenable to have some fun with a bet, because the outcome will be seen in a reasonable time frame. If for some a bet is not “serious” enough, we will follow it with a serious discussion of the scientific issues shortly. We think framing this as a bet with specified conditions will help to clarify what exactly it is that the authors are predicting - after reading the paper at first this was not entirely clear to us, and it clearly is not entirely clear to many of the journalists reporting on it either. -stefan]
8 May 2008 at 8:43 PM
I’m surprised that you’re asking for a meteor escape clause, but not one for the use of nuclear weapons.
8 May 2008 at 8:49 PM
RE #27
Ray,
Perhaps you should read Fooled by Randomness or The Black Swan by Nassim Taleb before you place your bet.
8 May 2008 at 8:54 PM
Re: #26 (Jim Cross)
The article is copyright of Nature, and it would be unethical to provide free access to an article which the copyright owners don’t approve. If you want to purchase access, you can do so through the Nature website.
What’s sad is that the denialosphere has made such a mockery of the Keenlyside et al. publication. The authors make it clear that they don’t disagree with the reality of global warming, but blogs everywhere are using it as a propaganda tool to paint global warming as a fraud and the climate science community as a bunch of confused clowns. I’d say that this RC article is an effective countermeasure in the propaganda war.
I don’t think bets prove anything, but if this proposal gets the point across then to the RC guys I say: good on ya. And as I said before, the data already available make it nearly impossible for Keenlyside et al.’s prediction for the 2000-2010 average to be supported by the data.
8 May 2008 at 9:17 PM
After a big meteorite hits, I don’t think anyone will worry about collecting on a bet.
8 May 2008 at 9:22 PM
regards #19: I read this week (probably in sciencedaily) that the geological evidence of the last Chaiten eruption shows a lot of ash, but not much SO2. If this bears out, even if the current eruption ended up being large (that is probably already only a small probability) the sulfates would still likely not be enough.
I’m not so sure about the effects of eruption latitude. My (nonexpert) recollection is the high latitude eruptions would mean most of the aerosols would end up in the hemisphere of the eruption. I would think that the overall effect on global average would be similar, but concentrated on one hemisphere only.
8 May 2008 at 9:55 PM
You need greater confidence than 50% to be motivated to make a bet. In some cases, much greater than 50%. Why? Because volatility destroys value (Sharpe Ratio). Depending on my utility curve and the size of the bet, I might need to be 99% sure or more before entering into the bet.
This is such a simple and common lesson in statistics that I find it hard to trust a statistical scientist who doesn’t understand it. In particular, I find it hard to believe that somebody would be employed in complex modeling tasks without immediate recognition of the application.
8 May 2008 at 10:04 PM
Perhaps I’m just out of touch with the times, but I agree completely with Chris McGrath in #33. This post would be crass even as an addendum to a serious discussion of the paper, but as a substitute for such a discussion (to be supplied at some future date) it’s an embarrassment. I don’t see why Tamino considers scientists engaging in a propaganda war a good thing - I haven’t seen him doing it.
8 May 2008 at 10:08 PM
Michael Mann,
as a follow up to your comment on volcanic aerosol transport, I was curious as to how fast anthropogenic aerosols are spread before they are removed, and if they are totally confined to the troposphere? They tend to have a reputation for being regional, but during the mid-century slight cooling, the Northern Hemisphere as a whole seemed to be effected.
8 May 2008 at 10:36 PM
Re # 33 Chris McGrath
“…I think it [this post] trivialises the issues involved…”
I disagree - there is nothing frivolous in this post. Besides, scientists aren’t dead serious all the time - they like to have fun. That’s why a lot of science gets discussed over beers at the pub during scientific conferences. If you are surprised by this, read James Watson’s “The Double Helix,” about the discovery of DNA structure. Or Horace Judson’s “The Eighth Day of Creation,” which gives an inside look at the scientists (including Watson and Crick) responsible for the revolution in molecular biology during the mid-20th century.
8 May 2008 at 11:45 PM
I find this post to be at best foolish and at worst reprehensible. To make the claim that if someone doesn’t accept your silly bet that they must not believe in their published article is childish. I would expect the same behavior from 10 year old boys on the playground. I am sure that the multiple authors of this article thought that this would be a good idea in the heat of the moment but I hope that they have the maturity to realize that it was poor judgment after a few nights sleep and pull this ludicrous article.
Is the new standard that all scientific articles should be judged by in the future? The scientist must not only put his reputation on the line by publishing the article for all to review and discuss but also must be willing to accept all monetary bets that dissenters throw out? To think that this site actually condemned others for paid speaking engagements in NYC a few weeks back. Where is the “discussing ideas and data in order to advance scientific understanding” (your words from your Jan 30 post).
What happened to the common courtesy of yesteryear when if there was a disagreement between gentlemen they shook hands and engaged in a “gentleman’s bet”. Even the crooks in “Trading Places” only bet one dollar when they ruined two peoples lives. Perhaps we should go back to the time of Hamilton and Burr and you guys can fight for your honor with dueling pistols.
I have typically publicly praised your site for its scientific knowledge. Now I have no choice but to write a rather viscious critique on my site that tries to discuss global warming with civility. At one time I thought this site was populated by scientists that were trying to explain complicated science. I guess I was wrong, it is run by children that want to show that they can beat up on others.
What’s next Mssrs. Rahmstorf, Mann, Bradley, Connolley, Archer, and Ammann? [edit]
9 May 2008 at 12:29 AM
Dear “scientists,”
I have a slight favor to ask of youz:
If you have a bone to pick with AR over his having ——-ed (supply your own descriptive verb) his reporting of the Keenlyside et al. paper, could you please send him an e-mail instead of blasting him in the NYT blog? It might be a more productive way of imparting better information. Thank you.
9 May 2008 at 1:05 AM
None of the forecasts appear quite right, they are too conservative, specially for the 2005-2010 period. Almost known to be quite warm. Gisstemp .76. .65 and .73 C for 2005-06-07. Higher than most previous years except 1998. Before someone is going to say something like Hadley is different than GISStemp etc, My work agrees indirectly with GISStemp, and above all other reasons, a Density Weighted Temperature of the entire atmosphere would make such surface temperature graphs or projections eventually obsolete.
9 May 2008 at 1:14 AM
Tamino are you saying that the bet is flawed because the Keenslyside paper is clearly and totally wrong or because the bet conditions are not in line with the paper’s predictions?
9 May 2008 at 1:23 AM
It is sad to me that a wager was made about our future climate. It may be somewhat in jest, but it now gives fuel to those who believe climate change (Global Warming has become a vilified word) is not real or just a money making scheme. I find that this could damage trying to get the message to ordinary citizens as it seems many on this planet are lemmings following the tune of the news media outlets and their agendas.
I am not a scientist nor am I anyone of great interest in the world but I actually do my own homework on this subject and find Climate change is real. Please Please retract this bet before it causes more damage to a science that becomes more politicized each day. The future of this planet should be more important than any ego here or of any scientist for or against this subject. Please think before you act in the future!
Sean Dorcy
9 May 2008 at 2:15 AM
Maybe we shouldn`t take models so seriously at all..
[Response: No–actually, it is comments such as this which we should not take seriously at all. -mike]
9 May 2008 at 2:34 AM
I’m a long time reader of Realclimate and have endorsed you, but I think this is a too polemic way to go about this. You should concentrate on the science where you rock.
Not everyone has the same amount of loose money, placing the poorer in a very different position when betting. Even if the odds were the same, they have a much worse outcome if they lose - this is not offset by the positive outcome of victory. (Well, depends on how risk averse you are too.)
All in all, it’s not very polite. There are people who are clearly dishonest hacks with whom politeness is not important, but I don’t suspect that with Keenlyside et al.
[Response: I would not bet with “dishonest hacks”, but I would with respected colleagues that I feel I’m on sufficiently friendly terms with. -stefan]
9 May 2008 at 4:15 AM
These sorts of bets also occur in Physics. I believe Hawking has (had) a few, for example. I *think* (could look it up) that there is currently one about whether the Higgs Boson will be detected.
But it’s not even new to Climate Science or RC:
http://www.realclimate.org/index.php/archives/2005/06/betting-on-climate-change/
9 May 2008 at 4:24 AM
The new decadal model forecast has little if any skill due to an important scientific concept. It is an initial values problem, and is thus contaminated by large sensitivity to intial conditions (weather noise). What you guys will not come clean about however, is that these initial conditions of the ocean/atmosphere also impart a large range of uncertainty on multi-decadal predictions, even though you are invoking changes in boundary values to gain skill. I have thought a great deal about this, and I believe yours is a lousy hypothesis. Since the long-term signal from the external forcing change does not diminish natural variability, all the modeler is left to do is make long-term projections that are so vague, as to reneder them practically useless to the public or policymakers (other than to mislead them into thinking that these are skillful forecasts when they are not). Then some climate modelers even have the audacity to publish regional “projections” saying that the Colorado River will dry up in 50-100 years, or the rainfall and temperature somewhere else will change this way or that. This is abuse of science in the worst kind of way.
It is double speak for a climate scientist to assert (correctly I might add) that natural variability like ENSO will alter the TOA radiative imbalance through changes in clouds, humidity, evaporation, rainfall, ect., but then out of the other side of the mouth imply that natural variability doesn’t really matter to the multi-decadal projections. It must. If you can’t keep up with annual-decadal changes in the TOA radiative imbalance or ocean heat content(because of failure to correctly model changes in the atmosphere and ocean due to natural variability), then your climate model lacks fidelity to the real world system it is tasked to represent. It might be said that such a model “is a uncertified public accountant of heat”. If either the model or the real system is a little “leakier” than the other, the two systems will diverge substantially over a long enough period of time. You gain a little heat in the model, or lose a little in the real world, and hope that the statistics of the long term natural variability go nowhere. Now the models may show this stability, but why should we believe them when they clearly don’t faithfully re-produce or predict some of the important atmosphere/ocean/cryosphere dynamics we are observing in the real world?
So I think in the final analysis, you can place bets one way or another, and try and qualify the ground rules in a way that increases your odds of winning, but this whole post is really a joke, and an unfortunate diversion from an important science discussion. It is good entertainment though. By the way, how’s the bet with Bill Gray coming? He is also predicting cooling based on something probably as or more reliable than the numerical models: His gut.
9 May 2008 at 4:26 AM
EU2.5K is a bit steep, what happened to a more sporting bet of say a subscription to Nature. What the bloggers rant about is irrelevant, most stories I spotted on Google news were reasonably clear about what was said in Nature. IMHO the Germans and Nature have done the art of climate modeling a favour. No matter who is right about the oscillating thingies effect on short term temprature, climate modeling will be the winner.
9 May 2008 at 5:00 AM
Personally I greatly appreciate RC posting on this topic because it was reported in the media (especially the Telegraph, BBC etc) as the gospel truth which is what happens as soon as something is reported in Nature or some other academic and well respected academic publication.
As RC are always at pains to point out to everyone, peer review is necessary but not sufficent to endorse something as true. The medias assumption that peer review means truth shows their lack of fundamental scientific understanding and hence the publics.
Great article RC, I reckon I understand where you are coming from and it also makes me wonder about academic institutions and scientists themselves. I guess that science itself has scientists and scientists is you catch my drift.
[Response: I think you understand the point we are trying to make. This supposed pause in global warming has been reported widely as if it were almost a fact, not a forecast, and as if this was widely supported by the climate science community, almost on a par with IPCC reports. Some articles framed it as if this new forecast now revises IPCC forecasts. If the prediction turns out to be wrong (which is what we think, and quite a few other climate scientists I have spoken to), this will damage the credibility of the whole community. This bet is supposed to signal to the public: on this decadal forecast the climate science community is not in wide agreement. In contrast to the global warming issue, where we have a wide agreement. -stefan]
9 May 2008 at 5:01 AM
Yours is a misleading and very weighted bet as others have already noted.
Would you be willing to take a bet that 2008 - 2017 will be cooler than 1998 - 2007? That would be a much more fair bet as to whether the mean average global temperature is going up or going down. It is easy to have bets when you pick the years that happen to suit your argument. Oh and I hope they do take your bet and that they win. 2008 has already shown precipitous cooling, if this continues (as it probably will) you may even lose your weighted bet.
Additionally IF you were to lose your bet, would you then admit that the earth IS cooling?
[Response: We bet against their forecast as they made it in Nature. We did not pick the years. -stefan]
9 May 2008 at 5:57 AM
Re #36 “What’s sad is that the denialosphere has made such a mockery of the Keenlyside et al. publication.”
I agree but isn’t this bet just doing the same thing? And that’s my point. The point of Keenlyside et al isn’t that global warming has stopped but the bet seems to be more to make a point against the position of the denialosphere than it is against the publication.
Is RC saying it is impossible that global warming might pause or not increase as quickly as some models project - that even a brief hiatus threatens the entire theory? I know it is not but the bet seems to be coming from precisely such a position.
9 May 2008 at 6:34 AM
Why don’t you take up an earlier suggestion from Ross McKitrick and endorse (in summary here) that GHG emissions be taxed proportional to the actual global temperature change?
That is better because reward is related to actuality, rather than guessing, as in your wager proposal, which is not actual. The former is better science than you propose.
Why not cool down a bit and come back with a more sensible proposition like Ross’s?
9 May 2008 at 6:43 AM
There is an excellent article on the Keenlyside Nature letter at ClimateProgress which gives a very good explanation of what Keenlyside’s analysis is actually about, and from where much of the confusion about how the model should be interpreted, has arisen:
http://climateprogress.org/2008/05/02/nature-article-on-cooling-confuses-revkin-media-deniers-next-decade-may-see-rapid-warming/
9 May 2008 at 6:51 AM
I think it would have been useful to point out how the media and blogosphere has wildly misinterpreted what the authors said:
http://climateprogress.org/2008/05/02/nature-article-on-cooling-confuses-revkin-media-deniers-next-decade-may-see-rapid-warming/
It is more accurate to say the Nature study is consistent with the following statements:
* The “coming decade” (2010 to 2020) is poised to be the warmest on record, globally.
* The coming decade is poised to see faster temperature rise than any decade since the authors’ calculations began in 1960.
* The fast warming would likely begin early in the next decade — similar to the 2007 prediction by the Hadley Center in Science (see “Climate Forecast: Hot — and then Very Hot“).
* The mean North American temperature for the decade from 2005 to 2015 is projected to be slightly warmer than the actual average temperature of the decade from 1993 to 2003.
I explain all this in the blog post.
9 May 2008 at 7:13 AM
Geoff Sherrington, Are you aware that what you are proposint is essentially a weather tax? Perhaps you’d advocate going a step further and having the tax vary throughout the day as temperatures rise and fall.
Those who are betting on temperature rising are betting on physics–and physics has a pretty good track record. Indeed if you understand the physics, it is very difficult to see how one could make any other bet. Policy should be based on the best science available as we understand it, and the science isn’t changing the answer it gives us. Because responding to climate change will require long-term investment in infrastructure, research and mitigation, we need an economic environment that is sufficiently consistent to reward such investment. An economic policy that changes with the weather doesn’t meet such a test.
9 May 2008 at 7:49 AM
Contrary what Alan (# 55) says, I think that climate modelling finally will be the loser. This bet is damaging and discrediting your profession more than anything else.
You should withdraw your bet and show some professional behaviour. Start professional discussions with your counterpart in Germany (and the rest of the world) without involvement of the Blogosphere in order to understand their position.
But who am I, a (climate) realist sensitive to listen to both sides of the issue.
9 May 2008 at 7:49 AM
BryanS, So what you are saying is that since we can’t predict weather, we can’t predict climate; that because we have influences that oscillate up and down and up and down that they will trump a forcer that increases monotonically; that because we do not understand everything, we do not understand anything? Sorry, don’t buy it.
By all means we must be cautious in extrapolating from long-term, global averages to regional consequences over finite intervals. However, we must weigh the consequences of the event as well as its probability, and over time, probabilities–and therefore risks–increase. If we have a threat with a possible consequence of the destruction of human civilization, we cannot dismiss that threat until we are certain that there is zero probability of that threat being realized.
The science of climate change is sufficiently settled that it is unlikely that what we learn in the future–and we have much to learn–is unlikely to significantly alter the likely consequences of a business as usual approach. We now have to look at how business as usual must change to become business as sustainable.
9 May 2008 at 8:26 AM
re: 57. We are talking about climate, not weather. Even if 2008 turns out to be relatively cooler, it is not significant to the long-term trend. Which is warming. Similarly, 1998 was unusually warm due to the fact that there was a strong El Nino that year which enhanced global warming. So using 1998 as a reference year for cooling is not accurate either as it was an enhanced warming year.
9 May 2008 at 8:28 AM
Jim Cross, I am well aware of randomness–it’s part of my day job. I am also aware that randomness in a system does not make it unpredictable over all timescales. Stocks follow a pattern of a random walk, but over the past several hundred years (admittedly an atypical period for human civilization), they have followed a random walk with a slight upward trend. Bet on stocks over the long hall over that period and you would have done quite well. Bet it all on any one stock or any one day and you could quite easily lose your shirt.
The desire to gamble is evidently part of human nature. Markets take advantage of this impulse to add liquidity to investments and thereby increase their value. Lloyds of London has made many people a good living over the years by allowing the wealthy to insure various propositions–in effect wagering. Moreover, life is full of probabilistic events for which it is very difficult to determine the probability distribution in any rigorous manner–either because they are inherently random, or because they are sufficiently complicated that rigorous determination is impractical. For such events subjective or Bayesian probability may be the only applicable technique, and betting is as good a way as any to determine such a subjective probability.
In effect the wager is being used to gauge relative confidence in two different models–a question that is not uninteresting or irrelevant to the science. It is rather like Fermi at Los Alamos taking bets on whether the Trinity test would initiate a catastrophic chain reaction in the atmosphere and incinerate the entire state of New Mexico: As Fermi was present at the test, his motive was certainly not profit, but rather to assess relative how much confidence people had that the test would not have catastrophic results.
9 May 2008 at 8:38 AM
I have read the Nature article, and cannot pretend to really understand it. From what I can gather, superficially, is that the authors took a climate model, with the same CO2 sensitivity as the IPCC, and modified it to account fot the Atlantic Meridional Overturning, which is a temporary phenomenon. Naturally, when this temporary effect disappears, the projected global temperature is the same as that forecast by the IPCC. What the paper does not appear to cover is where the heat from AGW “hides” in the intervening years. I apologise for the unscientific word “hide”; it is the beat I can come with to describe what I am trying to say. What is the physics of where the AGW heat goes between now, and say, 2015?
9 May 2008 at 9:25 AM
I believe model predictions have been the subject of bet challenges before (and no one has accepted one to my knowledge so why would this group.)
The bet would also need another escape clause; that of the metrics used to measure temperature. Some metric would need to be implemented to ensure the same system is used to measure temperature in the future given how often the methods are changed which have increased the temperature trend.
9 May 2008 at 9:39 AM
Another document to add to my archive of posts about warming, to be brought out to warm my heart during the bitterly cold winter of 2015…
But seriously…between the Keenlyside prediction and the long-standing predictions by some in the solar community of solar-induced cooling in the next decade, this is a pretty ballsy bet. One might describe it as prideful, even.
9 May 2008 at 9:58 AM
Re: #49 (Joseph Hunkins)
I don’t say the bet is flawed. I just note that one would be a sucker to bet on the 1994-2004 decade because much of the data have already been recorded, and the 2000-2010 decade already has a big, almost insurmountable, lead.
Re: #58 (Jim Cross)
Bingo!
9 May 2008 at 10:30 AM
I was going to ask the same question as Jim in #67. I asked one of the authors of the Hadley decadal forecast paper (that said “cooling from 2005 to 2008/9 then warming afterwards”) and he shrugged his shoulders and said “natural variability”.
If the Keenlyside forecast were correct, come 2015 what data will show us that the heat is indeed hiding and about to come out and cook us in 2030. Would such data be available?
Second question. Are realclimate confident because the forecast is “probably” wrong, or are there physical reasons for not believing the forecast could come true?
9 May 2008 at 10:32 AM
Wow, look how many crypto-deniers came out of the woodwork to denounce the awful bet. I’m wondering if some web site asked their readers to go deluge RealClimate with this stuff.
The reason they don’t want the bet is obvious — they know damn well they’re going to lose.
9 May 2008 at 10:38 AM
Put a bowl of water at 50C in your oven, preheated to 50C. What will happen? Will the water warm? The air in the oven?
Put a bowl of water at 1C in your oven, preheated to 50C. What will happen? Will the water warm or cool? Will the air in the oven warm or cool? If the air in the oven cools, where is the “lost” heat “hiding”?
When upwelling brings cold water to the ocean’s surface, cooling the atmosphere, where is that heat lost from the atmosphere “hiding”?
9 May 2008 at 10:42 AM
Online bet payment by anyone in the USA may run afoul of the ca-si-no protection provision slipped into the recent Port Security Act. Just saying, be careful transferring any wa-gered funds when the time comes.
9 May 2008 at 10:44 AM
Re #45 (Chuck Booth)
Yes, of course many things are talked about over beers at conferences. And by posting this bet RealClimate has reduced its level of discussion to that of slightly intoxicated researchers shooting the breeze after hours.
I know such discussions take place. I just don’t come to RealClimate to read them.
9 May 2008 at 11:38 AM
I’m of two minds regarding this post. Do bets cheapen science? Maybe. Is there potential for unintended effects in public perception? Sure — look at Ehrlich versus Simon. But I don’t think bets lower the quality of the discussion. Indeed, I agree that in this case the bet has served to crystallize just what the predictions are.
I wish, however, that just one RC author had done the post. With a bunch of you, some people have already decided that the bet is all of RC versus Keenleyside et al. People tend to generalize and I think there may be some other perceptual problems. A less emotional complaint is specific to the bet, which can be made complicated if one considers that it is 6 to 5 in people, even in currency, and likely uneven in wealth. How should a reader interpret that? In that regard, perhaps a gentlemen’s bet would be preferable, as presumably everyone’s honour is equivalent. Ack, then again, honour is probably not the primary motivator on the internet.
Maybe I’ll reserved judgment on this issue until the next post on the topic. I look forward to it!
9 May 2008 at 11:48 AM
Re: tropical vs high latitude volcanic eruptions — I know the effect is likely negligible, but tropical locations are selected for launches into space because of centripetal force, right? Is it possible for tropical eruptions to put more material into the stratosphere due to an assist from rotation of the earth? Note, Mike’s comment about the primacy of the distribution of material that makes it that high is well-taken.
9 May 2008 at 12:06 PM
They will both cool (the air in a preheated oven is quite dry).
It is hiding in the water.
In the ocean, but this is not the only place for the heat to hide. It could be hiding in melting ice, or through albedo changes there may be no added heat at all. Is it so unreasonable for someone to be curious as to what exactly is offsetting the greenhouse gas warming in the paper?
9 May 2008 at 12:41 PM
The latest SO2 figures for the ongoing Kilauea eruption is that the two active vents are releasing more than 3,300 tons per day. Which will total more than a million tons of SO2 this year if the eruption continues.
Will this have a measureable effect on climate?
Layman Regards - Phillip
9 May 2008 at 1:02 PM
Phillip Shaw: SO2 does have an impact on climate, but the natural Hawaiian SO2 emissions are tiny compared with what is coming out of China’s coal-fired power plants. It takes a really huge eruption, like Pinatubo, to noticeably affect climate.
9 May 2008 at 1:11 PM
I believe that Stephen Hawkins and Kip Thorne (who are very good friends) had a wager involving a substantial sum. I don’t recall what aspect of physics it was about or who won.
9 May 2008 at 1:13 PM
Re#13
“Minor(I think) nitpick. The end of the red line in the graph appears to end in about 1998, not 2004.”
Would it make sense to put yearly temperatures on the graph as well to see how the projections are doing like the BBC did? How do the recent faster rising European temperatures look on their European predictions?
9 May 2008 at 1:18 PM
I would accept your bet on the second forcast. If you have the oats to do it send me an email and we can make some agreement, including exchange rates cause my money is in dollars…
9 May 2008 at 1:20 PM
re#33
Glad to see RC give the correct interpretation of the hindcast/forecast plot, i.e. the forecast is cooling.
It took me a while to get my head around it, and I was in good company; ‘Figure 4 in the actual paper shows the global mean temperature trends and there is no projected cooling’ I wonder who said that
[Response: Oops. I was fooled by the green line in figure 4. That joins up different predictions but is not a trajectory itself. - gavin]
If the bet is accepted how will you include observational uncertainty? As the Hadley Center have uncertainties associated with them will you still win the bet if the globe has warmed but the error bars overlap with Keenlyside’s?
9 May 2008 at 1:30 PM
“In 1975, cosmologist Stephen Hawking bet fellow cosmologist Kip Thorne a subscription to Penthouse magazine for Thorne against four years of Private Eye for …”
http://en.wikipedia.org/wiki/Scientific_wager
Famous scientific wagers
9 May 2008 at 1:46 PM
Ref #73 by dhogaza. I think I understand the analogy as it pertains to the actual Atlantic Meridional Overturning, but I cannot follow how it explains what happens to the heat that accumulates as a result of AGW in, for example, the Sahara Desert, the Amazon Rain Forest, Antartica and Siberia.
9 May 2008 at 1:55 PM
As a long time reader of RC and a long aquintance with media, I understand the bet and your reasoning. As totally an other issue I also wish you are right in your estimate and hope warming would not take a pause at this time. I guess warming will necessarily have its ups and downs due to weather cycles but a long pause at this particular time would be devastating for both political and popular reaction and a quick rise afterwards would have more dire consequences than a steady rise for several reasons I will not go into now.
9 May 2008 at 2:01 PM
If you are confident you will win your bet then you should also give them odds.
10 to 1 or something will really show how confident you are.
[Response: Actually, they made a forecast and took it to the media. We proposed this bet because we want to see how confident they are about it. -stefan]
9 May 2008 at 2:05 PM
silence: According to the Hawaiian Volcano Observatory website, the normal SO2 emission for Kilauea is 150 - 200 tons per day. Thus the current emission of about 3,300 tons per day is around twenty times the normal level. And because of the recent activity at the Halemaumau caldera there is a good chance the eruption will intensify. The eruption was also featured on the NASA Earth Observatory website with an interesting image of the SO2 plume data from the Aura satellite. (Sorry, I don’t know how to add links to this post.)
My questions are: is a megaton release of SO2 during a year large enough to be measurable? And what magnitude of SO2 releases are the geoengineering proponents proposing to offset, not mitigate, AGW?
Thanks - Phillip
9 May 2008 at 2:14 PM
Stefan, In your reply to comment #56 you state “If the prediction turns out to be wrong (which is what we think, and quite a few other climate scientists I have spoken to), this will damage the credibility of the whole community.”—If the prediction turns out to be correct, will this too damage the whole community?
Tamino, in #70 you state “…1994-2004 decade because much of the data have already been recorded,”–[MUCH]—It is well into 2008, should not ALL of this data be recorded?
9 May 2008 at 3:14 PM
Have to agree with the crowd here, I think this is a poor way to judge confidence in the findings of the paper and a little below the level of discourse expected here.
I think a much more appropriate bet would have been for a more symbolic prize: i.e. We will send you shorts and flip flops, and you send us parkas, or a weeks cruise to the caribbean vs. antarctica.
9 May 2008 at 3:17 PM
It is when that person is Jim Cripwell, whose postings here make it clear that he’s a denialist…”offsetting greenhouse gas warming” presumes one accepts greenhouse gas warming in the first place, after all.
9 May 2008 at 3:35 PM
RE: #75
On Friday afternoons, RC becomes Gavin’s Garage (where the mechanics of climate chnnge gets discussed), and everybody get a little loose.
“…slightly intoxicated researchers shooting the breeze after hours…”
This is when you learn all about the stuff that didn’t work (Been there, done that!), saving you a lot of time and money and grad students’ sanity. On occasion you can learn some really interesting info about your friends (and enemies) present research projects or pick up a few nitty-gitty technical tips that just never get written done.
ATTN Gavin
At the next big conference, why don’t you set up an after hours workshop called “Gavin Gargage” where there will be copious quantities of free beer, snacks and munchies!
9 May 2008 at 3:53 PM
Re: #90 (Gaelan Clark)
Settling the bet requires collecting data through Oct. 2010, which hasn’t yet been recorded.
9 May 2008 at 4:01 PM
Hank Roberts (85) — Thank you for the link. Shows that at least some scientists are betting men…
9 May 2008 at 4:26 PM
At present I have not yet seen an analysis which shows this model to be rubbish. Just a lot of folks suggesting it smells improbably low. The principle of the BMA method in Douglass is that the average of several predictions is in general performs better than any individual projection. As it is a peer reviewed model, this model could reasonably figure in the IPCC model inter-comparison project and hence a possible Douglass et al 2011. Douglass weights all models in the IPCC model inter-comparison project equally. The ensemble would lose all predictive power regardless of what happened to measured global temp, as the error bars would be huge.
Is that about right or is there a reason this model would be excluded ?
Does anyone have ideas about if and on what basis this model should be excluded from an ensemble?
If it is on the basis of not being a full General Circulation Model would it still be excluded if it’s predictions were spot on? Whatever rules are suggested now could rubbish other models later, or even some of the 22 in the existing model inter-comparision project.
[Response: You have to compare like with like - so you can’t take this experiment and just throw it in with the standard runs discussed in AR4 - the likelihood of a significant structural bias is high. We’ll have a post about all the IPCC runs soon. - gavin]
9 May 2008 at 4:47 PM
Even casual observers need to cherry pick to back up cooling. Recent months in Australia have been strange. Sydney had the coolest summer (Dec, Jan, Feb) ever. In March (autumn) Adelaide had 13 straight days over 37.8C the old 100F. Other parts of Australia that need frost for horticulture are still waiting, yet we had frosts last summer. Whatever trend line there is has hit a patch of statistical noise.
9 May 2008 at 4:56 PM
RE #21 & “Shame on RealClimate for turning a serious scientific subject into a bet. If these authors are wrong please use the scientific method - evidence, reasoning, and yes climate models (if predictions vary) to convince others.”
Actually, this is good for me. I don’t understand a whole lot of climate science. Much of it goes over my head. But I do respect the expertise of the RC scientists. So any of them saying they’ll bet serious money that there will not be these 10 year average cooling or stable periods is just the kind of info I need.
Of course, I will also attempt to struggle thru their scientific explanations (Stephan did say he’d get to that in a later post), at least for a paragraph before throwing up my hands in surrender and turning back.
So now I have this idea that there probably won’t be a cooling period. And we really could have used one.
So it’s back to square one — prayer: “Heat, heat go away, little Johnny wants to thrive. And don’t come again another day.”
And back to good old GHG emissions reduction.
9 May 2008 at 5:00 PM
Phillip Shaw: I don’t have the most recent data at hand, but coal burning in China released about 25 million tons of SO2 in 2005. The increase Kilauea remissions may be smaller than the SO2 emission reductions that China is implementing to look clean during the Olympics.
9 May 2008 at 5:39 PM
In #79, Phillip Shaw wrote:
“The latest SO2 figures for the ongoing Kilauea eruption is that the two active vents are releasing more than 3,300 tons per day. Which will total more than a million tons of SO2 this year if the eruption continues.
Will this have a measureable effect on climate?”
Probably not. Kilauea lava is not very viscous, which means the eruptions are not explosive and do not inject the SO2 into the stratosphere. You might expect some temporary cooling of the ocean not to far downwind from Hawaii, but nothing more.
[edit]
Best regards.
9 May 2008 at 5:41 PM
[edit]
On the off chance, then, an observation: why would an escape clause be needed in the event of a volcanic eruption? Aren’t all natural and anthropogenic projections, in the aggregate, included in models that purport to be good predictors?
[Response: Because volcanoes are not predictable and do not form part of the Keenlyside et al experiment. Thus if one occurs then their scenario will no longer be valid, and the test moot. - gavin]
9 May 2008 at 5:49 PM
Authors,
There is a flaw in your betting proposal (unless I missed it above or in the subsequent comments). There is no expiration date! As is, the other team can wait 5 years to accept the bet! Legal scholars you’re not.
9 May 2008 at 6:40 PM
Re 80:
Has anyone modeled and published the effects of anthropogenic Chinese/ Indian aerosol emissions on monsoonal/ SE Asian climate?
9 May 2008 at 6:40 PM
Re 102: ” Legal scholars you’re not.”
Which is to their credit. I once went hunting with a neighbor who happened to be an attorney. We encountered a panther and he started running. I told him it was useless, that he couldn’t outrun a panther. He said that he didn’t have to outrun the panther,he just had to outrun me!
Referring to Lynn’s comment: “So now I have this idea that there probably won’t be a cooling period. And we really could have used one.”
There could still be regional cooling in places like in the north Atlantic, which could slowdown melting on Greenland, and give the world an opportunity to take advantage by putting the reduction of GHGs on the front burner asap to mitigate the effects of albedo reduction and sea level rise from that source, when the heat returns.
9 May 2008 at 8:02 PM
Re #64: Ray Ladbury, The type of prediction being tried in the new paper is certainly an initial values problem, much the same as weather prediction. Collins (2002) investigated this type of climate prediction, and found limited skill using a few metrics, in a few regions (one of these included the north Atlantic). In most areas there was essentially no skill. Now keep in mind that these runs assumed perfect initialization, and a perfect model, neither of which are possible in reality. Therefore, I have concluded that these types of forecasts likely have a poor chance of showing any skill, ever. Even if the initial atmosphere/ocean state could be estimated in an accurate quantitative manner, these will likely still hit the predictive wall owing to chaos. Remember that the ocean has a very long memory of initial conditions, and I doubt you wash these out even in multi-decadal predictions, but certainly not in decadal forecasts. Now it is a very big leap of faith to hold that initial conditions definately will not matter for multi-decadal evolution of the climate system as external forcing is perturbed. A big assumption is made that the natural variability of the ocean/atmosphere gets averaged out, and that this leads to no multi-decadal trend (statistical stability of the climate system). The only solid evidence of this is not observation, but rather another hypothesis, which is the model climate itself. Ray, what do you think happens to the system if there are a succession of big El Ninos followed by weak La Ninas or long neutral conditions. Then another big El Nino and a weak La Nina. Now flip the sequence over another period. These must have an important effect on latent and sensible heat fluxes from the ocean to the atmosphere, and ultimately influence the TOA radiative imbalance and the ocean heat storage. Now if the AOGCMs are not skillfully simulating tropical variability, you explain to me how they can possibly correctly model cloud and water vapor feedback correctly, and ultimately skillfully simulate the heat storage changes in the system? Think about this. The long memory in the ocean may mean it is still responding to intial conditions from sometime ago, and much of the intrinsic variability of the system is dictating these big radiative fluxes from ocean to atmosphere. Yes the GHG external forcing is giving the system a shove in the direction of warming, but there is a bunch more taking place. So with this reasoning, I have convinced myself that the initial conditions and short term variability of the ocean/atmosphere may well be very important in influencing the ultimate longer term trajectory of the climate system. The main longer term influence of relatively modest GHG forcing is to increase the probability that longer-term evolution of the system will be toward warming. Skillfully predicting the magnitude of such warming over even a multi-decadal time span is overselling the science in my opinion. Then trying to downscale to make regional predictions in this time frame borders on foolish. You are free to disagree.
9 May 2008 at 8:36 PM
Here’s another reference to this post at ClimateArk.org
http://www.climateark.org/blog/2008/05/climate_change_and_cooling_cli.asp
9 May 2008 at 8:54 PM
Tamino (94) or H. Roberts (85)
I will defend the science/logic and sociological arguments for the following bets.
1)The planet will abruptly cool because of the current solar magnetic cycle change. The solar cycle has been interrupted, cycle 24 will not appear. There be a recognized direct connection to planetary cloud cover and solar magnetic cycle changes and to galactic cosmic ray (GCR) changes. GCR has and will continue to increase until mid 2009.
2)Next winter will be the coldest winter in 50 years. There will be crop failures next spring and summer due to early and late frosts.
3)Global cooling will become a recognized environmental problem, in 2009. There will be proposals presented to stop global cooling.
4)The deep issues discussed in Anne Leonard’s story of stuff video will be discussed in 2009.
I do not have an answer to the problems raised by Anne Leonard.
http://www.storyofstuff.com/
Solar magnetic cycle update. Cycle 24 is a year over due, there are currently no sunspots.
http://www.dxlc.com/solar/
Ocean temperature anomalies.
http://www.osdpd.noaa.gov/PSB/EPS/SST/climo.html
9 May 2008 at 9:27 PM
Is it so unreasonable for someone to be curious as to what exactly is offsetting the greenhouse gas warming in the paper?
Yes, indeed it is.
From fundamental thermodynamics, if heat is being retained at the surface, and in fact is not radiating into space because of some feedback effects (clouds or whatever …) then it must be going into a colder reservoir, and we know exactly where those reservoirs are. Admittedly with the loss of Cryosat were are a bit behind the curve, and the response of the thermocline and deep sea currents is problematic at best, there is no question where the heat is going.
It’s melting ice and warming the ocean.
It’s a trivial thermodynamic result.
9 May 2008 at 9:43 PM
Because volcanoes are not predictable and do not form part of the Keenlyside et al experiment. Thus if one occurs then their scenario will no longer be valid, and the test moot. - gavin
Yes, but to win the bet you need warming, or at least less cooling, and you get that based on models that oppose the Keenlyside. Presumably you think the warmer models are more accurate, so is volcanic activity and the resultant cooling haze built into those or not? That’s my point — are the predictive models complete? And if not, what’s the utility of any model that needs to be excused when natural events occur?
[Response: Neither set of models have future volcanoes. Instead their trends are determined by the intrinsic variability in the climate and the far more predictable increases in greenhouse gases. Think of it like a train schedule - that is a prediction for when the train will leave but it doesn’t account for random things that might happen and so when they do, the schedule is thrown off. Yet there is still utility in having a schedule. - gavin]
9 May 2008 at 10:06 PM
Re Phillip Shaw #89:
To create links in your posts use the following HTML code
… <a href=”www.webpageaddress.net>This text appears in the post.</a>
Test it with the preview button before you post, it’s easy to get it wrong.
Gavin, I found this intriguing remark by you in the comments to the
Should we continue watching the space, or did you give up on the idea?
[Response: Continue to watch, but have patience. - gavin]
9 May 2008 at 10:43 PM
Re # 75 John Franklin: “…RealClimate has reduced its level of discussion to that of slightly intoxicated researchers shooting the breeze after hours.I know such discussions take place. I just don’t come to RealClimate to read them.”
Hmmm…that is precisely why I do come to RC. This is a blog, afterall. If I want peer-reviewed science, I’ll read the peer-reviewed journals, or IPCC reports. Instead, like Harold Pierce, Jr. (#93), I want to know what the climatologists really think, unconstrained by the formalities of a journal article. Since I can’t afford to attend AGU meetings, and wouldn’t be invited to drink beer with the scientists if I did attend, this blog is the next best thing to being there, or to sitting in on one of their laboratory meetings (or, joining their Friday afternoon sessions at the pub).
As for allegations that this post will hurt climatalogists’ credibility, I say, Give me a break! With all do respect to the RC staff, I think some of the critics of this post greatly overestimate the influence RC has on the general public’s understanding of global warming. At least in the U.S., if the general public knows anything about global warming (and, clearly, many people don’t), they probably learned it learned it from television, newspapers, news magazines, and, dare I say it, An Inconvenient Truth. I seriously doubt that millions of people are rushing home from work each day to read the latest RC post.
I’m not qualified to judge if the proposed wager is sound scientifically, or statistically, but as long as neither side has the power to alter the climate in order to win the bet, I’m confident the bet will have absolutely no impact whatsoever on the earth’s climate. Therefore, I see no reason to get upset about it. Your time and energy might be better spent debating the potential impact of the proposed summer-time moratorium on federal gasoline tax on CO2 emissions. Or, debating the scientific issues that prompted this wager in the first place.
9 May 2008 at 10:48 PM
Dhogaza@92
“It is when that person is Jim Cripwell, whose postings here make it clear that he’s a denialist …”
My hunch is his question in part stems from discussions between gusbobb and Gavin concerning gusbobb’s notions of ocean heat loss.
Recently there was a press release about a paper written by J. Willis:
Perhaps this exchange between gusboob and Gavin is what is driving his question:
gusbobb:
Jim Cripwell:
According to the press release, the Willis paper found the ocean was cooling slightly, but also found no corresponding reduction in SLR. Doesn’t that sort of point to the heat going deeper in the ocean?
9 May 2008 at 11:12 PM
Unless I read the WRONG paper, and I followed the link provided here, what I read
doesn’t seem to jive with any of the comments, other than one, that is being posted here.
What I got out of the paper was that their prediction hinges on
…”the current Atlantic meridional overturning circulation will weaken to its long-term mean; moreover, North Atlantic SST and European and North American surface temperatures will cool slightly, whereas tropical Pacific SST will remain almost unchanged. “….
And if such were to happen, isn’t their thinking along historical lines, another words they are more or less echoing a set of circumstances that predicated and brought in cold times in Europe
in the past due to a weak gulf stream that carries the warm weather up into Europe’s latitudes.
And this was released this week by UCAR
Climate Models Overheat Antarctica, New Study Finds
NCAR & UCAR Press Releases, (07 May 2008)
http://www.ucar.edu/news/releases/2008/antarctica.jsp
“”Computer analyses of global climate have consistently overstated warming in Antarctica, concludes new research by scientists at the National Center for Atmospheric Research (NCAR) and Ohio State University.”…”The error appeared to be caused by models overestimating the amount of water vapor in the Antarctic atmosphere, the new study concludes. The reason may have to do with the cold Antarctic atmosphere handling moisture differently than the atmosphere over warmer regions.Part of the reason that Antarctica has barely warmed has to do with the ozone hole over the continent. The lack of ozone is chilling the middle and upper atmosphere, altering wind patterns in a way that keeps comparatively warm air from reaching the surface. “…
9 May 2008 at 11:26 PM
Regarding 91: “Have to agree with the crowd here, I think this is a poor way to judge confidence in the findings of the paper and a little below the level of discourse expected here.”
Puhleez, this is how humans resolve it. Get off your high horse.
10 May 2008 at 12:10 AM
Actually as a framing device, I think the bet is a very good idea. Sometimes it just takes brute force to make people listen whenever science is the topic at hand.
10 May 2008 at 4:30 AM
re #41+79
The EOS Aura satellite has some good plots of the Sulfur dioxide from Chaiten, many orders of magnitude lower than Pinatubo (15-20Mt SO2)… so far.
10 May 2008 at 4:34 AM
#103 CW Magee,
Have you read this?
“Atmospheric brown clouds: Impacts on South Asian climate and hydrological cycle” Ramanathan 2005.
http://www.pnas.org/cgi/reprint/102/15/5326.pdf
Or this:
“Warming trends in Asia amplified by brown cloud solar absorption.” Ramanathan 2007
http://www-cas.ucsd.edu/personnel/vram/publications/Ram_etal_Nature2007.pdf
10 May 2008 at 5:43 AM
Ray Ladbury (no 64) “However, we must weigh the consequences of the event as well as its probability, and over time, probabilities–and therefore risks–increase. If we have a threat with a possible consequence of the destruction of human civilization, we cannot dismiss that threat until we are certain that there is zero probability of that threat being realized.”
The climate threat with the highest chance of destroying human civilization would be the next ice age. Are we dismissing that, or doing something to reduce its probability to zero?
“The science of climate change is sufficiently settled that it is unlikely that what we learn in the future–and we have much to learn–is unlikely to significantly alter the likely consequences of a business as usual approach. We now have to look at how business as usual must change to become business as sustainable.” No argument with this. But we are a long way from having the knowledge or the technologies to genuinely achieve this goal. (BTW, the second “unlikely” in the quoted passage should be “likely” or words to that effect.)
10 May 2008 at 6:13 AM
wmanny, perhaps you could come up with a model-crystal ball interface so the models could include this important effect on the WEATHER!!!! Until that point, all one can do is look at various runs with various volcanic aerosol contributions for potential effects and include a mean contribution in the models.
10 May 2008 at 6:19 AM
Alex Heyworth, Jim Hansen’s work has suggested that we are very unlikely to have an ice age with CO2 as high as it currently is. Therefore, I would say that the probability is certainly fairly remote. Also, I would contend that some of the warming scenarios Lovelock has painted hold equally grim prospects for human civilization and are more probable.
I agree, that a lot of work is needed to achieve sustainability, but starting now by serious conservation efforts, investment in alternative energy sources, etc. is a start and buys us the time we need to achieve this goal (hopefully, at least).
10 May 2008 at 6:28 AM
RE, Re #56, Another article appeared in the UK Daily Telegraph the other day regarding the Antarctic computers models being inaccurate for this region.
http://www.telegraph.co.uk/earth/main.jhtml?view=DETAILS&grid=A1&xml=/earth/2008/05/08/eatemp108.xml
However the DT tone for this article is far more downbeat and you would expect from a boradsheet newspaper.
10 May 2008 at 6:38 AM
Those who think that betting on scientific matters trivialises the issues should be aware that there is something of a tradition among scientists of betting on scientific outcomes.
For example, in 1997 Stephen Hawking and Kip Thorne made a bet with John Preskill of the California Institute of Technology who had argued that information carried by an object entering a black hole was not destroyed. Hawking famously lost when he changed his mind some 30 years after declaring that information entering a black hole would be destroyed. The prize in this instance was an encyclopedia “from which information could be freely retrieved”.
Another well known, still-unresolved bet was made by futurist Ray Kurzweil when he wagered $10000 against Lotus Development Corp founder, Mitchell Kapor. Kapor believes that “by 2029 no computer - or “machine intelligence” - will have passed the Turing Test” while Kurzweil takes the opposing view.
Ther are many others, as Hank Roberts link (#85) shows.
10 May 2008 at 6:40 AM
Ref 112 from RCH “Doesn’t that sort of point to the heat going deeper in the ocean?”
and # 108 Thomas Lee Elifritz “From fundamental thermodynamics, if heat is being retained at the surface, and in fact is not radiating into space because of some feedback effects (clouds or whatever …) then it must be going into a colder reservoir, and we know exactly where those reservoirs are. Admittedly with the loss of Cryosat were are a bit behind the curve, and the response of the thermocline and deep sea currents is problematic at best, there is no question where the heat is going.
It’s melting ice and warming the ocean.”
I do not hide the fact that I am a denialist. However, I am a scientist as well. If the heat we are wondering where it “hides” is, in fact, going into the oceans, then it cannot be going into the surface of the oceans, otherwise these would heat up, and the average global temperatures would rise. The forecast, from Keenleyside, is that this is not going to happen. So the heat must be going into the deep oceans. Simple physics says that warmer water is lighter, and therefore this heat should rise to the surface. I know it is much more complicated that this, and I know my physics isn’t good enough to work it out. But I can understand any arguments, based on fundamental physics, that proves this is the meachanism I am looking for. What I am looking for is a properly argued discussion that proves that a process that “hides” the heat in the deep oceans,(or anywhere else for that matter) exists. Until such a detailed paper has been published, I simply cannot accept the idea that this heat can “hide” anywhere. To me, this is simply, inadequate science.
10 May 2008 at 6:52 AM
Alex Hayworth writes:
Dismissing it. The next ice age is due 20,000-50,000 years from now. It’s something that can be calculated with fair accuracy, since it depends on the Earth’s orbit and other astronomical factors.
10 May 2008 at 6:56 AM
BryanS, I would qualify the effort as extremely difficult of having limited probability of success rather than foolish. It is hardly