Why the world’s top scientists underestimated how fast we’re destroying the climate

I have long argued the IPCC “consensus” grossly underestimated both the speed and severity of climate change (see my 2007 post, “Scientists are underestimating climate change, Part III“). That’s one reason I rarely use the term “scientific consensus” and prefer the term “scientific understanding” when discussing global warming (see “Disputing the ‘consensus’ on global warming,” which also discuss the many reasons that the IPCC lowballs its projections). My guest blogger today, Elizabeth Grossman, updates this story. She is author of the forthcoming book “Redesigning the Future” and is a frequent contributor to Earth Island Journal. This post was first published here.

The predictions about what climate change may bring are pretty dire, but now it seems, they were actually underestimated.

In its most recent official report, the Intergovernmental Panel on Climate Change (IPCC) significantly underestimated the amount of greenhouse gas emissions that would occur during the last seven years, a miscalculation that has put the planet beyond the “range of possibilities” considered by some of the world’s top climatologists. The overly optimistic predictions in the IPCC’s Fourth Assessment, released in 2007, appear to have been driven, in part, by the political dynamics involved in the international effort. The underestimation means that government negotiators meeting in Copenhagen later this year to write a replacement to the Kyoto Protocol will have a tougher task than previously imagined.

“We’re looking at future climate beyond anything we’ve considered,” Chris Field, director of the global ecology department at the Carnegie Institution for Science, told the American Association for the Advancement of Science (AAAS) annual meeting in Chicago last month. “Actual emissions are at or above the total range of possibilities considered in the IPCC’s Fourth Assessment.”

The underestimation of greenhouse emissions occurred, Field said, because the IPCC failed to include in its scenarios the rapid increase in carbon dioxide from Asia’s coal-reliant industrial expansion between 2000 and 2007.

“We were too optimistic,” Field said. “There was no decrease in emissions from developed countries and the sharpest increases and overall intensity came from China and India that rely heavily on coal.”

“It was assumed that coal would become less important,” says Ken Caldeira, also of the Carnegie Institution. What happened, however, is that China and India developed rapidly while rising oil prices pushed wealthy nations to use more coal, which is more CO2 intensive in its emissions. Scientists at NASA’s Goddard Space Science Institute concur that the past five years’ sharp increase in atmospheric CO2 is attributable to the steep rise in global coal use, pushed upward by accelerated Asian economic and industrial development.

“IPCC scenarios assume an increase in energy efficiency during this period,” Caldeira says. But that didn’t happen. “Efficiency flattened out,” he says.

Scientists involved in the IPCC process say that IPCC reports are designed to capture the long-term rather than short-term trends, and cannot incorporate data after a certain point, so the 2007 report relied on pre-2002 data. Nevertheless, widely available pre-2002 data would have suggested an upward trend in Asian emissions.

According to research by Kelly Sims Gallagher, director of the Energy Technology Innovation Project at Harvard University’s Kennedy School of Government, China has been a net importer of oil since 1993. During the 1990s, writes Gallagher, Chinese car sales grew about 27 percent a year, doubling the number of cars on the road every 2.5 years. The US Energy Information Agency data shows coal consumption by China and India approximately tripling between 1980 and 2005.

Given the fact that the breakneck economic growth in India and China were well known phenomena, how could the Nobel prize-winning IPCC have omitted an increase in Asian carbon emissions from its scenarios? The short answer appears to be politics.

“Social and political dynamics are at work,” in producing final IPCC reports, Fields said at the AAAS meeting.

Stanford University biology professor and climate scientist Stephen Schneider agrees. “The lead authors are constrained by government reviewers,” Schneider says. “The political process cuts the edges and doesn’t do a good job at the tails of the bell curve, which is where we are now.

“These reports are consensus documents and when it comes to politics, the interests of small island nations are different than those of the U.S., China, Russia, Saudi Arabia, and Kuwait.”

There is a political and diplomatic incentive to low-ball emissions predictions becaue lower numbers make the task ahead appear less onerous.

“Overtly or covertly, if you have an optimistic baseline of what happens in the absence of policy, it makes what you need to do appear relatively modest,” Caldeira says. “People who want to make the problem look more tractable have an incentive to make the baseline ore optimistic. If you have a more depressing picture, it’s more difficult to make the transition.”

For example, Caldeira says that if we’re to stabilize atmospheric carbon at what’s now considered tenable levels for the climate — about 350 parts per million (we’re now at about 385 ppm) — the world’s energy systems must be carbon neutral by mid-century. That’s a daunting task that many governments appear hesitant to grapple with.

Not only has atmospheric carbon increased beyond the range of possibilities, but so too has effects of that increase on Earth’s ecosystems. The retreat of Arctic Sea ice, the collapse of permafrost, ice sheet melt and that melting’s contribution to sea level rise are occurring faster and with more intensity than expected. Atmospheric carbon dioxide, Field said, rose 3.5 percent annually between 2000 and 2007, compared with annual increases of 0.9 percent in the 1990s. Between 1993 and 2003, melting ice sheets accounted for 40 percent of sea level rise. That contribution is now estimated at 80 percent.

“The more we learn about the process [of climate change], the more severe the risk becomes,” says Michael Oppenheimer, professor of geosciences and international affairs at Princeton University. Oppenheimer and Schneider are among the co-authors of a paper just published in the Proceedings of the National Academy of Sciences showing that the impacts of a 1-2°C rise in global mean temperature are much greater and pose greater environmental risks than previously anticipated.

Whether or not the Asian carbon surge continues, its impacts will be with us for decades — even centuries — because of the length of time carbon lingers in the atmosphere. “Nothing we could do now to stabilize carbon could be too fast or fast enough,” says Tom Athanasiou, director of the organization Eco-Equity, an Earth Island Insitute-sponsored project. “The storyline was wrong.”

The underestimation of recent greenhouse emissions threatens to complicate the work of government officials who will meet in Copenhagen in December to hammer out an international climate agreement to replace the Kyoto Protocol, which expires in 2012. With climate change occurring faster than scientists have the ability to predict — and the impacts greater than anticipated — an international deadlock is unacceptable, Anthanasiou says.

“Maybe the most important thing is to communicate the severity of the situation in a way that gets through people’s defenses,” he says.

[JR: And that is what Climate Progress is all about.]

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16 Responses to Why the world’s top scientists underestimated how fast we’re destroying the climate

  1. Joe, you are spot on.

    Your insight will either be accepted, ignored or reviewed by future historians seeking a better understanding of this blunder.

  2. paulm says:

    “Maybe the most important thing is to communicate the severity of the situation in a way that gets through people’s defenses,” he says.

    And now we must recognize that we have to apply this beyond the communication of the situation to action on the situation.

    I would say events have moved beyond the threshold, immediate action is now necessary, especially by scientist, as well as economist and those in positions of influence.

  3. paulm says:

    That Nobel prize is looking a bit tarnished!

    Not only are we all realizing (some saw this much earlier Gore, Hansen, Lovelock etc) that 1-2°C rise is going to be bad news, but we are now going to get 3°C+ whatever we do now.

    We now have to proportion a large part of our action and resources to mitigation, drawing them away from solutions and so exacerbating the whole situation.

  4. lgcarey says:

    And the longer we wait to undertake serious mitigation, the more we expose ourselves to the risk that we will actually have fewer available resources later than we have now. (That is, of course, contrary to the idiotic “truism” assumed by Nordhaus, et. al that future resources will always be greater than the present – all I have to do to figure out the lunacy of that view is to look at my 401K statement from a year ago).

  5. Gail D says:

    I would suggest that the way “…… to communicate the severity of the situation in a way that gets through people’s defenses,” …. is to make the message incredibly short, clear, hard-hitting and personal, as much as possible.

    I spent last Friday listening to and testifying to my state senate on the matter of an aging coal plant and if it makes sense to extend it’s life by adding the mercury scrubber that is currently mandated by the legislature.

    The point I want to make is that after eight hours of testimony, with every angle covered ad nauseam, the hard-hitting crucial take-home points were lost, or at best, substantially diluted by the enormity of the verbiage.

    I believe the public has a similar glazed look as did the senate committee members.

    It’s time to sound the alarm bells…(literally)! There is a global call to action. The message is simple… The time to act is NOW! We must come together within this country and among all nations to work harder and with more cooperation than has ever occurred… or even been imagined!

    We understood and rallied around the message that came from President Roosevelt when every citizen was called upon to do their part for the war effort.
    Similar engagement (but on an even grander global scale) is essential.

    Again, this has got to reach people on a gut level. That can only happen when the message comes from the top, but is reinforced constantly in our everyday lives… (as the home front and “Rosie the Riveter” posters did in WW11)

    Let’s sound the alarm… and have it on the networks as public service messages.
    The Bush administration did this surreptitiously, yet so effectively, with their plastic and duct tape fear campaign.

    So let’s keep the message simple and direct. As I recall, Paul Revere’s warning didn’t include footnotes.

  6. paulm says:

    …”It’s as if scientists know a bomb will go off, but can’t find the right words to warn the people who might be able to defuse it.”

    Climate change blues: how scientists cope;_ylt=AoikLyPrA8Au7frzm741UNNpl88F

    The bomb has gone off….we are all sitting here waiting for the firestorm to rush by…

  7. On the other hand, I have had several intelligent, politically aware friends tell me that the sense that it’s already too late leads them to a point of paralysis.

    But perhaps people with those attitudes were always beyond reach, anyway.

  8. Misha Jacoby says:

    I was very surprised to find no mention of “Global Dimming” in this article.
    Could it be possible that a significant number of “top scientists” are unaware of this scientifically verified phenomenon. If you are among them, you may start here:

    Hope this issue starts getting a lot more attention and begins being factored into the equations.

  9. Dorothy says:

    One of the things that concerns me is that the sustainablitiy folks may be inadvertantly impeding people/voters from thinking about what they really need to do to reduce not just CO2 emissions, but the atmospheric CO2 content.

    One of the activists where I live speaks of our town as being successful in cutting emissions. She points to the fact that we now have a community bus, so people here have an alternative means of transportation. Nonetheless, our total emissions continue to rise, with more light trucks now on our roads. And people, feeling good about our ‘success’ don’t feel appropriate outrage at the negligence of our federal government.

    Thank you for posting this article, Joe. If anything can cause the seeds of dissent to sprout, this should.

    We also posted one you might want to today by an Australian earth and paleoclimate scientist: Copenhagen Climate Change Conference News –

  10. Martin Hedberg says:

    All the carbon that is brought up from the ground will eventually turn up in the atmosphere or ocean. Whatever carbon from biomass that is cut down and not reforested will do the same.
    Isn’t it time to go from talking about cutting emissions to actually stop the carbon at its initial source?
    And we must not forget the effect of aerosols (for example the atmospheric brown cloud), both warming and cooling – definitely affecting climate and ecosystems. Most of it comes from inefficient burning of biomass. These problems can be addressed by fairly simple technologies. Why don’t we?
    But again, whatever carbon that the mining/energy company brings to the surface will within a few months increase the greenhouse effect or lower ocean pH.

  11. Arjan Wilkie says:

    In relation to global dimming; a recent book called “Climate: Code Red” talks a lot about this factor and the aerosol effects of cooling generally.

    The biggest surprise for me was that efforts to remedy particulate emissions (smog. soot) will reduce this cooling effect and this will then add about 0.5 to 1 degree to the warming trend, so its the case that the smog is masking some of the warming attributable to Co2. When we reduce fossil fuel use as we are compelled to do (esp. coal) these particulates will diminish and so to will the aerosol effect. So global dimming is not actually great news – it is more bad news.

    Interestingly, this “aerosol effect” is the science behind geo-engineering proposals in relation to using sulphur compounds in the upper atmosphere (to be released by airliners, so the idea goes). This will continue the global dimming cooling but without the associated Co2 emissions that currently underpin it. These ideas are only suggested in the context of ‘desperation stakes measures’ to buy us time to decarbonise our energy production systems.

    I fear we are in for a “lovelockian” population collapse, as any species that overshoots the carryng capacity of their local environment must experience. It is depressing, i have 3 small kids.

  12. Harrier says:

    I suppose, in the end, my one concern is that Earth is able to continue to support human life. How much human life, and in what kinds of forms and concentrations, doesn’t matter as long as that life is able to endure in a fundamental sense.

  13. jorleh says:

    And scientists were hiding the facts they knew, all other but Hansen. They were hiding behind politicians. I think the silenced scientists are as guilty as politicians. Remember Galileo…

  14. underestimated says:

    Nice but wrong title. What scientists have underestimated is the rate of increase of CO2. Whether they have underestimated its consecuences or not remains to be seen. But according to what we have seen so far in the 21st century, it seems like the warming will be less than estimated. Current temperature trends are nearly outside the 95% confidence interval of the average of the models predictions… because of actual temperatures not being as hot as predicted. This can be weather of course. Or it can be not. But the thing is that you cannot claim that you have underestimated warming when all you can actually see in the temperature trends is an overestimation.

  15. David B. Benson says:

    underestimated — Nope. Still within the error bars.

  16. Correcting myself… or rather extending my thanks to Elizabeth Grossman for this article .. and to Joe for bringing her to us as a guest posting.

    Looking forward to the book.