Science: Global Climate Report

Juliet Eilperin
Washington Post Staff Writer
Monday, February 5, 2007; 12:00 PM

There is no longer any reasonable doubt that human activities are warming the planet at a dangerous rate, according to a new worldwide assessment of climate science released by the authoritative Intergovernmental Panel on Climate Change.

With at least 90 percent certainty, the IPCC's "Summary For Policymakers" concludes human-generated greenhouse gases account for most of the global rise in temperatures over the past half century. Hundreds of scientists from 113 countries prepared the report, which represents the most comprehensive overview of scientific climate research since 2001.

Discuss the report (pdf) with Washington Post staff writer Juliet Eilperin on Monday, Feb. 5 at Noon ET.

The transcript follows.

Read more in the stories:

* Humans Faulted for Global Warming. (Post, Feb. 3)

* AEI Critiques of Warming Questioned. (Post, Feb. 5)


Rockville, Md.: No doubt that it is getting warmer? Of course not and not for a long time. However there is a move to push those who want to ask another question into the the "no warming camp."

My question is "Will warming be good or bad?" and I ask it because an ice age caused by astronomical factors would be a good reason to want to warm the Earth. I agree it is not likely, but I am not sure that we have fully explained the ice ages or their causes. I also know that some crops will be better off with a longer growing season - as cotton in North Texas. It may be a good political move to say an argument is all one sided, but science is not well served until we know all of the factors.

Juliet Eilperin: You are right that some regions will benefit from climate change while others will not. Regions of the world that already experience water and food shortages, such as many countries in Africa, will be worse off, while the opening of the Northwest Passage could benefit some shipping companies, for example.


Washington, D.C.: Dear Ms. Eilperin, Thank you for your reporting on an important issue. Are there Senators or House Members who still openly express doubt about climate science showing significant man-made warming? Are there interest groups aside from "big oil" which argue against the conclusions of mainstream climate science? Thank you.

Juliet Eilperin: Sen. James Inhofe (R-Okla.), the top Republican on the Environment and Public Works Committee, still expresses doubt about global warming. I don't know of any others, though there may be. I don't know of any think tanks who question the current scientific consensus on global warming who do not receive industry funding, though they may exist. Even Patrick J. Michaels, a senior fellow at the Cato Institute, said on PostRadio on Friday that he believes human activity contributes to global warming.


Anonymous: Why isn't the Washington Post covering the story of the American Enterprise Institute's attempts to bribe scientists $10,000 to write reports that contradict the IPCC? (As reported in the UK Guardian, Reuters, etc.)

Juliet Eilperin: I wrote a piece on this that appeared in today's Post.


Washington, D.C.: Juliet, From your perspective, what is the single most important thing that we (as citizens), governments, and private sector can each do to counteract the increasing Co2 concentrations and associated climate change trends?

Juliet Eilperin: The response depends according to the sector. Private citizens and companies make the most difference by promoting energy efficiency, which can entail everything from installing compact fluorescent light bulbs to using public transportation. Governments bear the responsibility of deciding how best to reduce greenhouse gas emissions society-wide, which is what Congress and the president are debating right now.


It's Me: A simple question - why is it the case that we have testable predictions of future weather in short-term forecasts (such as the snow forecast last week) that are regularly proven wrong very often (like when not a flake fell last week), but the predictions out 1,000 yrs by scientists regarding global warming are taken as absolute fact?

Juliet Eilperin: That's a very interesting question, and I'm not quite sure I know the answer. I would assume it has to do with how variable weather is on a daily basis, as opposed to long-term trends. I've spent a lot of time talking to computer modelers lately and I know they feel more confident about their predictions now as opposed to 10 years ago, and I also know that earlier IPCC predictions have turned out to be largely accurate (if a bit conservative). One advance in recent years is that scientists have become more skilled in meshing real-world observations, such as ocean temperature readings and glacier melt measurements, with computer modeling.


Silver Spring, Md.: There is very little doubt about Global Warming. But even if there were, it would still be better to take all possible precautions to counteract its effects, rather than wait for the most dire consequences. We always insure against risk, even when we do not believe that an adverse event might occur.

Juliet Eilperin: That is the argument of politicians such as Sens. John McCain (R-Ariz.) and Barack Obama (D-Ill.), both of whom made that point in testimony before the Environment and Public Works Committee last week. Others, such as President Bush, say it is too expensive for America to talk such precautionary measures (when it comes to caps on carbon dioxide emissions).


Mt. Lebanon, Pa.: Has anyone to your knowledge prepared a graphic showing ocean level rise and how it would affect populated regions of the world? I mean a real topo map, not a written list.

Perhaps scientifically-prepared - as opposed to politically assembled - visual aids would awake public awareness from the continuing coma of environmental degradation and disaster. Imagine the Washington monument with its feet perpetually wet. Thanks much. Registered Engineer

Juliet Eilperin: I don't know if there is such a map, though scientists regularly discuss how some islands in the South Pacific and Bangladesh would be among the first nations to become submerged. In the U.S., Florida, Louisiana and Manhattan would all be affected by rising sea levels.


Arlington, Va.: Hi Ms. Eilperin, In contrast with Europe, it seems the American public is not very concerned about global warming. In addition, it seems the American press doesn't feel they have to balance any report on global warming by quoting a skeptic. It seems that this is because the issue got politicized here like nowhere else. Would you agree with me, and can you tell me who initially politicized the issue?

Juliet Eilperin: I think the issue is politicized (as you'll see from some of the questions I'm getting today). I would guess that both sides, the left and the right, have helped politicized the issue. However, I disagree with you in the sense that American reporters sometimes quote skeptics, but since the scientific consensus is so overwhelming on what is causing climate change, I think reporters a) don't feel the need to constantly quote a perspective that is so marginal in academia and b) it is simply hard to find a credible scientist who questions humanity's impact on the climate. Also, Americans are increasingly focused on global warming as an issue, both because politicians are starting to talk about this and also b/c of Al Gore's movie, "An Inconvenient Truth," which was released last year.


Alexandria, Va.: What is the source of funding for this group?

Will they increase their likelihood of future funding (or publicity) by biasing their results to a more alarming conclusion?

"There is no longer any reasonable doubt..." followed by, "With at least 90 percent certainty...."

It appears that there's at least a 10 percent doubt... great journalism!!!

As a physicist, I find it hard to accept any of this garbage as anything close to scientific... simply agenda promoting coupled with typical fear-mongering journalism.

Juliet Eilperin: The IPCC is funded by the UN, though all of the hundreds of scientists who work on its reports do so for free. And I doubt the authors care that much about getting press-after all, they only publish reports every five or six years.

By saying they have at least 90 percent certainty, the IPCC actually is saying scientists are b/w 90 and 99 percent certain humans are responsible for recent climate change. So I would say that is neither "garbage" nor "typical fear-mongering journalism."


College Park, Md.: I'm a physicist from U. Maryland. In answer to an earlier question, James Hansen at NASA Goddard, has numerous "what will be underwater" discussions for different climate models. Check out his report to the NAS.

Juliet Eilperin: Thanks, this is helpful to readers.


South Carolina: The major issue in global warming is one that is often ignored in most articles intended for lay people, and which you touched on but did not describe. One of the catastrophic scenarios that could result from melting of ice sheets and snow is a slow down or stoppage of the Atlantic Gulf Stream, which keeps much of Europe and parts of North America temperate. If the influx of freshwater into the oceans caused salinity to decrease, the warm waters of the Gulf stream would not be sucked into the North Atlantic, essentially stopping any flow of warm water or air towards Europe. Stoppage of the Gulf Stream could, in effect, cause a new Ice Age, making Western Europe, Iceland, Greenland, and parts of the Atlantic coast uninhabitable. This is the issue most people do not understand, that results of climate change does not end with warmer temperatures in winter, but can have more catastrophic, unforeseen effects. Why are these points often ignored by the media?

Juliet Eilperin: This is something I've written about, but one of the issues is scientists do not expect this scenario to play out in the next century, which is generally what they focus on. The IPCC just reported that its scientists do not envision this happening by 2100, though it added it could occur during the next 1,000 years.


Washington, D.C.: People who are skeptical of global warming consistently cite the negative impact on the economy that carbon caps would have. Is this true? Or could it possibly usher in an era of renewed R and D, innovations in science, and other benefits? Also, what's the state of Europe's carbon trading system? I've heard some people have made fortunes from it. thanks!

Juliet Eilperin: As with any shift in federal regulation, there are winners and losers. Clearly some new technology companies would benefit from a carbon cap, such as wind turbine producers and solar energy companies. Utilities that are heavily invested in traditional coal-fired power plants, by contrast, would take a hit. I've had a hard time, to be honest, determining exactly what economic impact a carbon cap would have on the U.S. because the groups that prepare such estimates usually have an axe to grind.


Kensington, Md.: I have to say I cringe whenever I hear people (typically from the "skeptic" camp) question whether global warming is necessarily a bad thing. These people exhibit a dangerous unfamiliarity with the potentially catastrophic nature of the mathematical concept of chaos. You simply cannot take a system as dynamic and nonlinear as the earth's climate - which has long sat in a region of reasonable equilibrium - and just "give it a shove" like this and expect it to settle comfortably and calmly into some "new normal" which might also have some nice side benefits. There is virtually no assurance that things will not "snowball" out of control when you do this. This is why many of the predicted effects of GW are counterintuitive (greater extremes, including cold snaps, etc.). Or, in simple folk wisdom terms, it's not nice to fool with Mother Nature.

Juliet Eilperin: I think this raises an interesting point-namely, there's a chance that the climate could respond in some drastic ways to an increase in greenhouse gas concentrations in the atmosphere. Certainly, many scientists, and some policy makers, tell me they are worried about this.


Washington, D.C.: Do you intend to report on other sources of income that the IPCC scientists receive (governments, foundations, companies), besides the AEI money?

Juliet Eilperin: As a policy, I always identify environmental groups as advocacy groups, which I believe gives readers a sense of their perspective. As for individual scientists, most of them get the bulk of their funding from universities and the federal government (which in recent years, of course, has been the Bush administration). So I don't think it's the best use of my time to investigate the source of funding of every single climate scientist in the U.S.


Washington, D.C.: Is there a single federal agency tasked with coordinating steps to control global warming? If not, which agency is likely to be able to do the most about the problem?

Juliet Eilperin: There is no single agency dealing w. climate change. The Commerce Department oversees a lot of the science that's conducted through the National Oceanic and Atmospheric Administration, the Environmental Protection Agency works on this issue a lot, and several other agencies, including the Interior Department, also have some jurisdiction.


projected flood maps: Here's a panable-zoomable Google map combined with NASA flood maps. You can enter the number of feet in sea level rise to see the area of interest greyed from the flood. -

Juliet Eilperin: For readers who are interested...


Reston, Va.: Hi. Was hoping you might get to the question about the polling of corporate execs on this question--a la the polling that is regularly done on the prospects for the economy. In this case, do you (exec) believe climate change is an issue and what can and should your company/corporation do about it. My question was "has this kind of polling be done or is it contemplated." This people have the power to make changes needed to address the challenge. But will they lead or will they wait for something else--legislation, e.g.?

Juliet Eilperin: I've checked and I can't find a formal poll on corporate executives when it comes to climate change, but Steve Mufson and I wrote a front page story just after Thanksgiving about how many top U.S. corporate executives are pushing for a a carbon cap. (Some of these include DuPont, GE, Duke Emergy and Exelon.) Many corporations at this point are interested in having regulatory certainty, and would like Congress to act.


Alexandria, Va.: To the skeptics out there, I would ask a simple question: Would you park your car in your garage and sit there with the motor running? Of course not. In doing so you would alter the chemistry of the atmosphere inside the garage in a way that endangers your life. In a similar way we have altered (and continue to alter) the chemistry of the entire atmosphere in a way that, increasingly, threatens to make our environment far less hospitable to human life. Such a change in atmospheric CO2 concentrations occurred naturally about 250 million years ago, with catastrophic results for life -- a mass extinction. So, anyone with an instinct for self-preservation should take heed and respect what science has to say.

Juliet Eilperin: I think this comment doesn't really need me chiming in, though I will say I know some parents often keep their cars running for more than an hour at a time so their small children can continue to sleep. So there are people in Washington who do actually do what this reader is writing about.


Falls Church, Va.: If the biggest adverse effect from climate change to humans will likely be rising sea levels, are there any engineering solutions to lower sea levels?

for example, could we pump sea water into low areas on Earth such as the Dead Sea or Death Valley? my back of the napkin calculations tells me that would lower sea level by a few meters. what about pumping water down to the poles so it can freeze? to me, climate change is now an engineering problem and we need to all put on our thinking caps ...

Juliet Eilperin: Obviously some people are examining engineering responses to rising sea level, though I don't know how effective these responses might be.


Hartfield, Va.: Isn't the essence of the IPCC news simply that more scientists now believe in a causal link between human-induced C02 concentrations and temperature rises? Don't significant uncertainties remain about the dimensions of climate change over the next century? And in view of the uncertainties, aren't such apocalyptic scenarios as 20-foot sea level rises, collapse of the Gulf Stream, and extinction of polar bears misleading and inflammatory?

Juliet Eilperin: A significant portion of Friday's IPCC report addressed future climate changes, including the disappearance of summer sea ice in the Arctic, for example. So it's not accurate to say that the survey only focused on the link b/w human activity and climate change.


Why not "virtually certain": How come the IPCC didn't just come out and say that it is a "virtual certainty" that humans are causing climate change?

Seems to me one reason is this: There are a lot of IPCC scientists, and they invariably had differing opinions. So, there were likely some dissenters who said, "no, it is not virtually certain, or even extremely likely." So, doesn't this mean that there may in fact actually be "reputable" climate change scientists who, in fact, are NOT virtually certain (or even 90 percent certain) that humans are causing climate change?

Juliet Eilperin: I'm not sure whether any IPCC scientist suggested there was less than 90 percent certainty that humans were warming the earth. There were some government officials that wanted stronger language in the document and some government officials that wanted weaker language in the document, so I think that in that particular instance, it was a question of politicians characterizing the science, rather than scientists.


Re: It's Me: In response to the question, how can scientists predict future climates but can't predict rain tomorrow, the simple answer is thus: climate and weather are two different phenomenons. It is really comparing apples and oranges, and while climate can affect weather (rain or snow?)it does not influence pressure systems (cause of rain or snow).

Juliet Eilperin: This comment speaks for itself.


Arlington, Va.: Do you know the capabilities or limitations of solar power? I have heard there is huge potential, but also understand that it is not receiving the attention or funding it may need. Do you have any input on it?

Juliet Eilperin: I'm not an expert on solar power-it really is a question of where you live, obviously, since some places are better suited to it than others. I know many solar power companies say they can be competitive with traditional forms of energy if the government gives them equivalent subsidies and tax credits, since coal, nuclear and oil and gas companies already enjoy assistance from the federal government.


New Hartford, Conn.: Juliet- thanks for convening this discussion. In response to some questions on sea level rise, the U of Arizona has done extensive mapping of the US coast, and Dr Matthias Ruth at U of Maryland has done more local scale work, for example, working with the Boston, Mass., region to show, the next house that will fall into the water in Nahant. Insurers are already using these models to determine coverage, and premiums. On the weather v. climate issue. A couple things are going on. One is that the weather models used today have as "normal" data a 30 year period from say 1961-90 or 1971-2000. The climate is changing faster than these models can keep up. This is why forecasts for three days out are often incorrect. In terms of the longer time scales covered by climate models, these are global scale with literally thousands of data points from land and sea stations. The predictions about temperature increase 30 or 50 years from now is from today's baseline and for a particular region. We don't have the technology to forecast that on February 5, 2049, Alexandria is going to be 3.7 F warmer than normal, and no one would ever say that anyway. What you see though are regional level forecasts based on the global scale models. For more info on this, google "Northeast Climate Impacts Assessment", headed up by the Union of Concerned Scientists.

Finally, with respect to the few remaining members of the skeptics, ignore them. Businesses are already moving ahead, and these skeptics are paid to say what they do, and that includes "elected officials". Note who their campaign contributions are from. and thanks to Judith for pointing out that AEI link.

Juliet Eilperin: This is also helpful for readers.


McPherson Square: Just wondering, if the "third world" countries develop AND the US and others cut their emissions, will they balance? Seems like China, India, Africa, etc. will be developing and they're not being asked/required to cut back and I'm not saying they should. Can the industrialized countries cut back enough? Hasn't US has reduced our rate of growth, so things are being done. That's the overall problem, other's rates v. the industrialized countries.

Juliet Eilperin: This is a very important question and a number of policy makers, from Sen. Dianne Feinstein (D-Calif.) to Rep. Mark Kirk (R-Ill.). argue China and India need to be brought into any international carbon emissions scheme in order to address the impact of developing nations. Within a matter of years, for example, China will outpace the U.S. as the world's biggest emitter of carbon dioxide.


Washington, D.C.: The Worldwatch Institute just released a book that focuses on the role cities will play in the future--given that 50 percent of the population will soon live in urban areas. It seems that cities might be heavily affected by global warming, but also might be able to help counteract increasing GHG trends. Is this touched on in the IPCC report?

Juliet Eilperin: Many cities are joining together to alter the way they operate-in fact, former President Bill Clinton is heading a coalition aimed at doing exactly that, so cities can increase their purchasing power and share policy ideas. I'm signing off now, but thanks for all the good questions.


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