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Is Joe Romm a ‘Global Lukewarmer’?

By Chip Knappenberger -- September 24, 2009

“On our current emissions path, we’re going to … warm more than 4°C by century’s end.”

– Joseph Romm, Climate Progress, August 11, 2009

I will be happy to bet anyone that the 2010s will be the hottest decade in the temperature record, more than 0.15°C hotter than the hottest decade so far using the NASA GISS dataset.  Any takers? Andy [Revkin]?”

Joseph Romm, Climate Progress, September 22, 2009

In a fit of rage, uber-alarmist Joe Romm of ClimateProgress has recently offered a temperature warming bet that he can win even if more than 85% of all climate models are shown to overpredict future warming.

Has Joe seen the light and become a “lukewarmer”—that is, someone who thinks that the human CO2 emissions will result in only a modest rise in global temperature, somewhere at or below the bottom end of the IPCC range of projections? Might he even be a closet ‘skeptic’–not a skeptic of climate change or anthropogenic climate change, but a doubter of climate alarmism?

For someone so strident on this issue, I would have thought that Joe Romm, would bet on climate catastrophe, not climate-model catastrophe.

Romm issued his bet after hyperventilating about Andy Revkin’s recent article in the New York Times, which suggested that the lack of change in the world’s average surface temperature since the turn of the century (or in some instances, a few years prior) has the potential to make it difficult to get CO2 emissions regulated in the name of “global warming.”

For what it is worth, I agree with Revkin on this (tune in next week to see why), as do an increasing number of science writers who are hedging their bets in line with recent data and what new peer reviewed articles are suggesting. And Romm is furious that Revkin has ‘mainstreamed’ lukewarming in the pages of the newspaper of record, the New York Times.

States Romm: “I will be happy to bet anyone that the 2010s will be the hottest decade in the temperature record, more than 0.15°C hotter than the hottest decade so far using the NASA GISS dataset.”

Well, many climate realists the world over would feel vindicated if the average temperature of the 2010s was only 0.15°C hotter than the decade of the 2000s (the current warmest decade). For that would provide more strong evidence that the earth’s climate was responding to anthropogenic greenhouse gas emissions in a far more benign manner than the ensemble projection of climate models.

In fact, the rejoicing wouldn’t be limited to climate realists but to just about anyone overly concerned about the potential for large negative impacts from climate change given a slower-than-model-predicted evolution of global temperatures. I imagine, though, that Joe Romm would be an exception because while he would have won the bet, he would have lost his Hell-or-High-Water war. He is emotionally attached to the issue with a public record of alarmism that is beginning to put Paul Ehrlich in the shade. (John Holdren, with his billion-death climate scare still on the table, might be another story.)

How Will the Bet Play Out?

When the final global temperature numbers are tallied at the end of this year, the hottest decade on record will be the most recent one, that is 2000–2009. The average global temperature anomaly in the GISS dataset for this period will be somewhere around 0.51°C.

Joe wants to bet that the next ten years, the “2010s” (2010-2019) will average at least 0.15°C hotter, or, that the global average temperature anomaly for the period will be at least 0.66°C.

Obviously, there are many ways for this to happen. I’ll examine a reasonable and straightforward one—I’ll assume that the evolution of global average temperature during the next 10 years will be just like it was during the last 10 years, but that each year will be 0.15°C hotter than the corresponding year 10 years prior. This reasonably captures interannual variability and is as good a guess as any as to how the temperatures could change and Joe could still win his bet. The resulting temperature history, from 2000-2019, is presented in Figure 1.

Figure 1. A reasonable temperature evolution in which Joe Romm would win his bet that the decade from 2010–2019 was at least 0.15°C hotter than the decade from 2000–2009. The closed circles are the observed data from the GISS dataset, and the open circles are the temperatures for the period 2010–2019 under the assumption that each is 0.15°C warmer than the corresponding year 10 years earlier.

The trend in global temperatures over the 20-yr period depicted in Figure 1—one in which Joe would win the bet—is 0.136°C/decade.

In Figure 2, I plot the distribution of the temperature trends as projected to occur during the first 20 years of the 21st century by all the climate models included in the IPCC’s Fourth Assessment Report when run under the mid-range emissions scenario called A1B (note: Joe thinks that this emissions scenario is far too conservative—which means it produces too little temperature rise for his taste). There are 55 model runs from among the 22 individual climate models.

Figure 2. (top) Frequency distribution of climate model projected temperature trends during the first two decades of this century under the SRES A1B emissions scenario (55 model runs in all). (bottom) Percentile plot of the model projected temperature trends from the 55 individual model runs with Joe’s winning bet indicated.

I indicate in Figure 2 where the trend 0.136°C (Joe’s winner) falls in this distribution. It falls at the about the 13th percentile, meaning that 87% of the model runs project that a greater temperature rise should have occurred during the first two decades of the century.

In other words, Joe won his bet and yet 87% of climate model runs (using an emissions scenario that Joe considers to be too conservative) projected that the climate should have warmed up faster than what occurred. Hopefully, by then, Joe would have reassessed his stance on the pace and impacts of global warming.

If Joe were really serious that he thought that climate models were getting things right (or even underestimating what is to come), then he should not have offered such a wimpy bet.

Man Up: A Real Romm Bet

At the very minimum, Romm should have offered a bet for a temperature rise during the coming decade that would at least have fallen in the middle of the distribution of model projections (if not higher since he considers that A1B underestimates the forcing changes to come). The 50th percentile of the model distribution is a 20-yr trend of 0.21°C/decade. For that to happen, the 2010s need to average about 0.25°C above the average of the 2000s (Figure 3).

Figure 3. A reasonable temperature evolution in order to bring the overall trend from 2000-2019 up to the model median value of 0.21°C/decade. Each of the coming 10 years would have to be 0.25°C hotter than its counterpart 10 years prior.

Clearly Joe needs to rethink his bet. For I am sure that he doesn’t want to include the possibility for it to result in a Pyrrhic victory. So, instead of offering up something on the namby-pamby side of things (which seems to run counter to his character), he ought to put something strong and confident out on the table—at least a bet that the 2010s will minimally average 0.25°C above the past decade’s average temperature, but even more impressive would be 0.30° or 0.35°C.

Come to think of it, if he really believes the “doubled” warming projections from the MIT study that his is so keen on touting, he ought to man-up and proffer a 0.50°C average temperature rise during the next decade as a reasonable 50-50 value. That would certainly cement his reputation as a true believer.

Offering anything less, would indicate that Joe really isn’t all that convinced that global warming is going to progress at rate leading to “unmitigated catastrophe.” Offering to bet on a 0.15°C rise is more like something I would put up (if I were the betting sort)!

So is Romm a closet “lukewarmer?” Or is he starting to become a bit worried that global warming is being a bit overblown? He has already reversed course to endorse a very weak climate bill (Waxman-Markey, what James Hansen called a “monstrosity”) as “the only game in town.” Perhaps he is unwittenly softening his physical science view as reality too.

So here’s a challenge to Joe (‘I’m-right-you’re-wrong’) Romm: will you offer a global warming alarmism bet instead of a ‘global lukewarming’ one? Will you walk your scary talk?


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  2. rbradley  

    Roger Pielke Jr. posts at http://rogerpielkejr.blogspot.com/2009/09/joe-romm-lukewarmer.html:

    “Romm has painted himself into a corner (and not for the first time). Will he escape with silence or bluster? Or will he actually walk his talk? The climate corner of the blogosphere awaits his monumental decision. Meantime, it is just a bit embarassing to be caught out as being so inconsistent.”

    My prediction is that Romm will ignore–he no longer debates and does not allow me to comment on his website. He is “battening the hatches” as the intellectual storms gather around him, is the way I interprete it.


  3. bill allen  


    According to the site above 1934 is the hottest year on record and three other years in the 30s are in the top ten. That means that the decade of the 30s is the hottest on record. NASA/GISS is the least accurate data base available because Hansen is cooking the books by not correctly factoring in the effects of the “urban heat effect”!

    Also, even the IPCC has stated that the cooling will occur for at lest the next decade. There is no way that the next decade will be the hottest.


  4. cknappenberger  

    Mr. Allen,

    Thanks for your interest in my post, I appreciate the sentiment, but you have gotten a few things wrong in your comment.

    The link you provided is to the US temperature record. In my post I am referring global temperatures.

    If you don’t like the GISS record, here is a link to the NCDC global temperature record. You’ll see that the warmth in recent decades dwarfs that of the 1930s.

    Also, the IPCC most certainly does not expect that in the global temperature record, “cooling will occur for at least the next decade.” In fact, they wrote (IPCC AR4, p. 12) “For the next two decades, a warming of about 0.2C per decade is projected for a range of emissions scenarios. Even if the concentrations of all greenhouse gases and aerosols had been kept constant at year 2000 levels, a further warming of about 0.1C per decade would be expected.”



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  6. James Taylor  

    I submitted the following comment on Romm’s blog:

    Joe, according to your beloved IPCC and your alarmist pals, temperatures should rise at least 3 degrees Celsius over the next century. That averages out to 0.3 degrees Celsius per decade. Why are you willing to place money on only HALF that amount of warming? I think this tells us something about how much even the alarmists doubt their own predictions of gloom and doom.

    Also, it is interesting that you specify the James Hansen-doctored GISS temperature compilation, which suspiciously is the extreme outlier among temperature data sets. How about a temperature report that is a little more objective?

    Joe, I will wager whatever amount of money you choose that the 2010’s will be less than 0.3 degrees Celsius warmer than the current decade, according to the objective satellite temperature data.

    Do I have a taker?

    To which Romm responded:

    I understand you deniers are stuck in linear thinking, where the future is always exactly like the past, but if you had any familiarity whatsoever with the scientific literature, then you would know that climate warming is not a linear phenomenon, it is an accelerating phenomenon, in part because of well-known delays in the equilibration of global temperatures with all the exogenous forcings and in part because of positive, amplifying feedbacks in the carbon cycle — the impact of global dimming is also relevant to the recent and near-term trend line, for those, unlike you, interested in actual science.

    I was offering a specific wager to call out the various deniers out there, like you — it was not a statement of what I expect will happen over the next decade, as regular readers fully understand. But if we were to apply the linear thinking and literalism that you seem to be stuck in, then your own offer is a stunning admission by a leading global warming denier that you believe there is a 50% chance warming will be 0.3°C or higher in the next decade! Kudos for your late-to-the-game climate realism.

    More seriously, the fact that you would accuse one of the top climate scientists in the world of doctoring data, when his work has been subject to extensive peer review over many many years and you are simply allowed to repeat long-debunked falsehoods again and again, however, makes clear to any independent observer that your words are not to be trusted.

    I submitted a follow-up comment, but Romm has blocked it from appearing on his site. My comment reads:

    “Joe, thank you for your reply. I admire your dedication and passion for your beliefs, although I disagree with them. Three questions:

    1) If global warming is an accelerating rather than a linear phenomenon, then why did more global warming occur in the 30 years between 1910 and 1940 than the 30 years between 1979 and today? (see NASA satellite data at http://www.drroyspencer.com/)

    2) If all temperature compilations except for Hansen report that 1998 — rather than 2005 — was the warmest year in the recent temperature record, then doesn’t a scientific “consensus” indicate that you and Hansen are wrong? Indeed, when such a substantial percentage of the temperature reports reach the same conclusion, could it not be said that “the debate is over”?

    3) At 0.3 degrees Celsius, I am already giving you a cushy proposition. Whenever I watch alarmist presentations or participate in debates with them, they almost always assert a warming of AT LEAST 3 degrees Celsius this century, and usually more like 4 degrees Celsius (or a pace of 0.4 degrees per decade). So at 0.3 degrees next decade, I am letting you wager on the low end of alarmist assertions. That being said, I will be still more generous and offer the wager at 0.25 degrees Celsius over the next decade. Interested?”

    Several scientists and global warming experts report that they, too, have been blocked from submitting comments in the “comments” section on Romm’s blog. Given the professional tone of my comment that Joe blocked, we can safely assume his reasons have nothing to do with maintaining proper decorum, and everything to do with being unable to present lucid arguments on his behalf. After all, why WOULDN’T Romm welcome critical inquiries on his website that he can publicly defeat and thus bolster his own argument?

    What are you afraid of, Joe, your own over-the-top global warming predictions? Why are you afraid to post questions and comments – in the portion of your blog specifically set up for them – that cordially question your assertions? My offer to wager on global temperature remains open. I am letting you claim victory even if temperatures next decade warm at a pace that is 42 percent BELOW your own predictions. Why won’t you accept my offer, Joe, do you privately acknowledge far less of a “crisis” than you are publicly asserting?

    “[W]e need to get some broad based support, to capture the public’s imagination. That, of course, means getting loads of media coverage. So we have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of any doubts we might have. Each of us has to decide what the right balance is between being effective and being honest.” – Joe Romm’s friend, Stephen Schneider.


  7. Andrew  

    James-how is .3 C “cushy” for Romm? .15 is cushy-that’s why he chose it.


  8. James Taylor  

    Andrew, allowing Romm to place a wager on 0.3 C is “cushy” because he predicts at least 4.0 over the next century, which would entail a pace of 0.4 per decade. A wager at 0.3 gives him a substantial cushion where he can win the bet even if global warming is 25 percent less than he projects.

    Sure, 0.15 is “extra, extra cushy” for him, but 0.3 is quite cushy also. Note that he also refuses to accept my 0.25 wager. If Romm even remotely trusted his won predictions, he would have pounced on my proposed wagers.

    Heck, I’ll even give him a wager at 1.9. That means he can win the bet even if global warming is less than half his prediction. Joe, do you walk the walk, or do you simply talk the talk?


  9. James Taylor  

    I submitted yet another follow-up comment on Romm’s blog just now. It reads:

    “Joe, I see that you have declined to publish my follow-up comment. Why is that? Do you not have any answers to my questions, or do you fear seeing my follow-up wager proposition in print?

    Heck, I’ll even lower my proposed wager to 0.19 degrees Celsius next decade. That means you can win the bet even if global warming occurs at a pace that is less than half your prediction. Joe, do you walk the walk, or do you simply talk the talk?”

    Anybody care to guess whether Romm accepts the offer? Anybody care to guess whether he blocks it from appearing on his site?


  10. Svempa  

    I’ve posted on Joe Romm’s blog accepting his terms and offering to bet USD 1000 that he is wrong. For me, this bet is just silly, there will be no warming at all during the next decade and the probability of cooling is quite large, considering that the coming solar cycle is even-numbered and also supposed to be considerably weaker than almost any solar cycle in the last 100 years.

    Joe Romm has not answered me, and actually I would not be surprised if he ignored my posts (I have posted in two discussion threads to get his attention). But I sincerely wish he would put his money where his mouth is :-)!


  11. Mark Bahner  

    Hi Chip,

    Thought you might like to see the comments that were too hot for Joe Romm to handle (so he deleted them from his blog…without of course even leaving any record they had ever been on his blog):

    “So the planet can warm, say, 0.2°C next decade — just as it warmed 0.2°C this decade, using NASA’s data, which is probably the best — and still warm 5°C this century, if we don’t act quickly to reverse emissions trends. That said, I am expecting the planet to warm more than 0.2°C next decade, particularly if there is not a major volcano.”

    “Yes, the planet CAN warm 5°C in the century, even after only warming less than 0.5°C in the first 20 years of the century. Just like Tim Jeter CAN raise his lifetime batting average 10 points in the remainder of his career. But the question is, WILL that happen? If you don’t quote odds, you’re essentially not making any claim.

    The NASA GISS global land and sea anomaly will most likely be 0.51 deg C for 2000-2009.

    What is your prediction for the *most likely* temperature anomaly each decade from 2000 to 2100 (i.e., the temperature anomaly for which there is a 50 percent chance of the actual rise being less, and a 50 percent chance of the temperature anomaly being more)?

    Decade……..NASA GISS Anomaly (deg. C)
    2000 – 2009…….0.51
    2010 – 2019…….????
    2020 – 2029…….????
    2030 – 2039…….????
    2040 – 2049…….????
    2050 – 2059…….????
    2060 – 2069…….????
    2070 – 2079…….????
    2080 – 2089…….????
    2090 – 2099…….????

    I’ve always wondered if Joe Romm really believed any of his scary predictions. Apparently not.


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