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M.I.T. Doubles Its 2095 Warming Projection To 10°F — With 866 Ppm And Arctic Warming of 20°F
Joe Romm, 21 May 09

Today's question: How the heck does the Greenland ice sheet survive accelerated disintegration from projected 20°F warming by the 2090s?

I previously blogged on how the Massachusetts Institute of Technology Joint Program on the Science and Policy of Climate Change has joined the climate realists — the growing group of scientists who understand that the business as usual emissions path leads to unmitigated catastrophe (see "Hadley Center: "Catastrophic" 5-7°C warming by 2100 on current emissions path" and below).

Back in January, the Program issued a remarkable report in January, by over a dozen leading experts, doubling their 2095 warming projection to 5.2°C. The media mostly ignored it, which is no surprise, since the media generally ignores the realists in general (see U.S. media largely ignores latest warning from climate scientists: “Recent observations confirm … the worst-case IPCC scenario trajectories (or even worse) are being realised” — 1000 ppm

Now, the MIT study has been published in a peer-reviewed journal -- The American Meteorological Society's Journal of Climate (subs. req'd) -- which obviously it makes it much more credible and high-profile. Reuters has a good story on it, "Global warming could be twice as bad as forecast." The study concludes:

The MIT Integrated Global System Model is used to make probabilistic projections of climate change from 1861 to 2100. Since the model's first projections were published in 2003 substantial improvements have been made to the model and improved estimates of the probability distributions of uncertain input parameters have become available. The new projections are considerably warmer than the 2003 projections, e.g., the median surface warming in 2091 to 2100 is 5.2°C compared to 2.4°C in the earlier study. Many changes contribute to the stronger warming; among the more important ones are taking into account the cooling in the second half of the 20th century due to volcanic eruptions for input parameter estimation and a more sophisticated method for projecting GDP growth which eliminated many low emission scenarios.

[Note: That rise is compared to 1981-2000 temperature levels. So you can add at least 0.5 °C and 1.0 °F for comparison with pre-industrial temperatures, which I did in the headline -- see "A (Hopefully) Clarifying Note on Temperature."]

The MIT press release calls for "rapid and massive" action to avoid this. Study co-author Ronald Prinn, the co-director of the Joint Program and director of MIT's Center for Global Change Science, says, it is important "to base our opinions and policies on the peer-reviewed science... There's no way the world can or should take these risks." Duh!

Their median projection for the atmospheric concentration of carbon dioxide in 2095 is a jaw-dropping 866 ppm.


Projected decadal mean concentrations of CO2. Red solid lines are median, 5% and 95% percentiles for present study: dashed blue line the same from their 2003 projection.

As grim as this prediction is, it is still almost certainly an underestimate of what will happen on our current path of unrestricted greenhouse gas emissions, as Prinn explains:

And the odds indicated by this modeling may actually understate the problem, because the model does not fully incorporate other positive feedbacks that can occur, for example, if increased temperatures caused a large-scale melting of permafrost in arctic regions and subsequent release of large quantities of methane, a very potent greenhouse gas. Including that feedback "is just going to make it worse," Prinn says.

Speaking of feedbacks, the model shows staggering warming near the poles (see “What exactly is polar amplification and why does it matter?“):

Figure 9: Latitudinal distribution of changes in SAT in the last decade of 21st century relative to 1981-2000. Red solid lines are median, 5% and 95% percentiles for present study: dashed blue line the same from Webster et al., (2003).

Median arctic warming -- north of 70° latitude -- (from 1981-2000 levels) is 20°F! How could Greenland's ice sheet possibly survive that?

Why the change in the 2009 modeling, compared to 2003? The Program's website explains:

There is no single revision that is responsible for this change. In our more recent global model simulatations, the ocean heat-uptake is slower than previously estimated, the ocean uptake of carbon is weaker, feedbacks from the land system as temperature rises are stronger, cumulative emissions of greenhouse gases over the century are higher, and offsetting cooling from aerosol emissions is lower. No one of these effects is very strong on its own, and even adding each separately together would not fully explain the higher temperatures. Rather than interacting additively, these different affects appear to interact multiplicatively, with feedbacks among the contributing factors, leading to the surprisingly large increase in the chance of much higher temperatures.

The carbon sinks are saturating, and the amplifying feedbacks are worse than previously thought -- that, of course, is a central understanding of all climate realists (see Study: Water-vapor feedback is "strong and positive," so we face "warming of several degrees Celsius" for links to the various feedbacks that have been ignored by most climate models).

Andrew Freedman at had one of the very few stories on this important study back in February and reprints this useful figure from MIT:


He explains:

Results of the studies are depicted online in MIT's "Greenhouse Gamble" exercise that conveys the "range of probability of potential global warming" via roulette wheel graphics (shown above). The modeling output showed that under both a "no policy" scenario and one in which nations took action beginning in the next few years to reduce greenhouse gas emissions, the odds have shifted in favor of larger temperature increases.
For the no policy scenario, the researchers concluded that there is now a nine percent chance (about one in 11 odds) that the global average surface temperature would increase by more than 7°C (12.6°F) by the end of this century, compared with only a less than one percent chance (one in 100 odds) that warming would be limited to below 3°C (5.4°F).

To repeat, on our current emissions path, we have a 9% chance of an incomprehensibly catastrophic warming of 7°C by century's end, but less than a 1% chance of under 3°C warming.

"The take home message from the new greenhouse gamble wheels is that if we do little or nothing about lowering greenhouse gas emissions that the dangers are much greater than we thought three or four years ago," said Ronald G. Prinn, professor of atmospheric chemistry at MIT. "It is making the impetus for serious policy much more urgent than we previously thought."

The time to act is now.

This piece originally appeared in Climate Progress.

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They are desperate to brainwash people to force us to swallow the global warming/cap and trade scam.

Those brainwashed to the point of wanting to destroy the economy to "prevent global warming" are behaving like the most primitive human beings, who allowed their witch doctors to kill and sacrifice their own people believing that killing and sacrificing others would ensure them good weather. Human beings don't have the power to control climate! And killing the economy does not help the environment. Just look at Haiti!

No patriotic and informed American can support the global warming/cap and trade scam, more fraudulent than any Nigerian scam. Cap and trade is a huge tax on the poor and the middle class designed to give the powers of a dictator to Obama and to further enrich his billionaire friends (Gore, Soros, Goldman Sachs, Obama’s Chicago Climate Exchange friends, GE, etc.)

Cap and Trade “would be the equivalent of an atomic bomb directed at the U.S. economy—all without any scientific justification,” says famed climatologist Dr. S. Fred Singer. It would significantly increase taxes and the cost of energy, forcing many companies to close, thus increasing unemployment, poverty and dependence.

More and more scientists and thinking people all over the world are realizing that man-made global warming is a hoax that threatens our future and the future of our children. More than 700 international scientists dissent over man-made global warming claims. They are now more than 13 times the number of UN scientists (52) who authored the media-hyped IPCC 2007 Summary for Policymakers.

Additionally, more than 30,000 American scientists have signed onto a petition that states, "There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gases is causing or will, in the foreseeable future, cause catastrophic heating of the Earth's atmosphere and disruption of the Earth's climate."

We pray that honest leaders – both Democrat and Republican - are able to save us from Obama's criminal global warming/cap-and-trade scam.

Posted by: AntonioSosa on 21 May 09

Please leave the above comment. It is not abusive. Just, well, an example of how some people think.

"All lies and jests. Still, a man hears what he wants to hear, and disregards the rest." - Simon and Garfunkel

Posted by: Tony Fisk on 21 May 09

I misread the headline, and thought that MIT had revised their January report to 10°, as in celcius.

Not that I'd have been entirely surprised given how fast things are changing but...

Here's the thing. I think you can see how seriously the Amereican administration took that report in January by the changes that are happening thick and fasst. that and the UK Meterological Office report swhich confirmed the same findings have made big waves on a global level. The most interesting changes of direction are coming from China.

All we can do is continue lobbying, and hope.

Posted by: Cait on 22 May 09

We're done.

If everyone is hoping for that 1950's sci-fi world of everyone working together to 1) battle aliens 2) evacuating the earth before the moon smashes into us or 3) or change the rotation of the earth to stop the earth from "falling" into the sun, you are all insane. I love those movies showing various former enemies at the UN hugging and shaking hands, all with concerned looks of trying to save humanity.

Unless all the republicans suddenly get a clue, a lobotomy or vanish from the earth and the rest of the world willingly cuts emmisions by 80% right now, this moment, not by "2020", then maybe, MAYBE we will have a slight chance.

I vote for a new race of mole people. eating mushrooms isn't all that bad. Grubs and other critters will take up the food chain slack.

we are sooooo done.

Posted by: Thomas Jefferson on 22 May 09

I thought MIT had some smart people?? Up north in MN my septic system has frozen 2 of the last 5 years and the well froze out last year. Those are "real" facts - not computer models.

Posted by: northman on 23 May 09

Where is the peer review. Real science requires peer review, testing of hypothesis, trying to prove your points. Please point me to where this is happening, I don't see it. I do see it on the skeptics side but not on the pro side.

Shutting down debate is not makes the pro warming side the creationists in the scenario, not the evolutionists. Real science requires real data, not computer models. Software can be written to provide anything the authors want to prove.

Let's stop the name calling that ends the debate and actually start the debate. If there is GW, it will be proved and we will not destroy on economy on it. If it does not exist, that will be proved also.

This is not the middle ages. We shouldn't burn books because we pick one side over the other.

Which side is closing the debate? That should tell you alot.

Posted by: Real Science on 23 May 09

I see the problem, clearly. Please list some solutions as well. Ones that the people who read this - mostly ordinary citizens, can implement.

Posted by: Vikram Jain on 24 May 09

Joe, thanks and a suggestion/request. Thanks for the update, I remember reading your original on this back in Feb. 09 or so. Now some for the most powerful suggestions are also the simplest, so here it is, my request: Create graphics like the two circles above but in FAHRANHEIT. US citizens are much more used to F than C and the C numbers look artificially "smaller". Don't throw away the C circles, we all know science is done in C, but complement them with circles with Fahrenheit readings, please, and post them! Thanks.

Posted by: ED on 24 May 09

Frankly, who cares if the Polar Ice melts since it is the short-term we need to be focused on. It is very unfortunate that the MIT climate model omitted natural methane emissions (that is the current situation with virtually all climate models because they can't accurately quantify the amount of natural methane emissions, it is simply omitted rather than estimated), and therefore is still badly underestimating the rate and severity of future global warming. What most people don't realize is that methane is 70 times more powerful than CO2 for the first 20 years (this is a better expression of CO2(e) than 23 times more powerful over the lifetime of the two gases). In other words, a ton of carbon can be CO2 or CH4, and therefore vary in greenhouse gas strength by 70 times in the short term. Furthermore, methane trapped in ice has more carbon than all the oil, coal, and natural gas still in the ground. It has been estimated that half of all surface permafrost will melt by 2050 (over 90 percent by 2100). That is not even counting the melting submarine permafrost!

Posted by: Brad Arnold on 29 May 09

""There's no way the world can or should take these risks," Prinn says. And the odds indicated by this modeling may actually understate the problem, because the model does not fully incorporate other positive feedbacks that can occur, for example, if increased temperatures caused a large-scale melting of permafrost in arctic regions and subsequent release of large quantities of methane, a very potent greenhouse gas. Including that feedback "is just going to make it worse," Prinn says." --"Climate Change Odds Much Worse Than Thought," ScienceDaily, 20 May '09

"The alternative (to geoengineering) is the acceptance of a massive natural cull of humanity and a return to an Earth that freely regulates itself but in the hot state." --Dr James Lovelock, August 2008

The world's emissions of the main planet-warming gas carbon dioxide will rise over 50 percent to more than 42 billion tonnes per year from 2005 to 2030 as China leads a rise in burning coal, the U.S. government forecast on Wednesday. China's coal demand will rise 3.2 percent annually from 2005 to 2030, the Energy Information Administration said in its International Energy Outlook 2008. --Reuters, 26 June 2008

Posted by: Brad Arnold on 29 May 09

I keep reading these horrible predictions. Worse and worse for every model put out there. And in addition there are the comments posted claming gross underestimates due to the effects of methane and so forth.

I must say - man made or not: Not like we are presented with a problem that has a solution.

Posted by: Magnus on 7 Jun 09

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