OPINION/COMMENTARY

Not So Dire After All

This morning the U.N. Intergovernmental Panel on Climate Change released its Fourth Assessment Report, but just in the form of a 12-page Summary for Policymakers. The report itself, about 1,600 pages, will be available only in May. The IPCC explains it needs time to adjust the scientific report to make it consistent with its summary. The summary actually is a semipolitical document negotiated by delegates from 150 governments. Evidently, the IPCC, which prides itself on being strictly scientific and policy-neutral, wants to make its report politically correct. This raises legitimate doubts about the scientific credibility of the IPCC's conclusions. The cleansing of the report — and the attendant delay in publication — is also feeding wild speculation about climate catastrophes, with many leaks to compliant newspapers. Compared to earlier reports, the Fourth Assessment is really quite sober, perhaps because a real scientist less given to ideology heads the effort. The summary projects slightly lower temperature increases than previous reports, for example. Also, the last report, in 2001, featured the Hockeystick, a graph that purportedly illustrated that the 20th century was unusually warm. Its underlying science was flawed by incorrect statistics, and apparently the IPCC now implicitly agrees, for the Hockeystick does not appear in the summary. The IPCC's estimates for sea-level rise are about half of previous values given. The IPCC is under attack by extremist scientists who think it is too optimistic and that the numbers should be more catastrophic. NASA scientist Jim Hansen's sea-level value is about 20 times higher than that of the IPCC. I suppose that makes him, as well as Al Gore, a climate contrarian. Notwithstanding these more restrained points, the IPCC fails to provide any real support for its key conclusion: It is very likely that anthropogenic greenhouse-gas increases caused most of the observed increase in globally averaged temperatures since the mid-20th century. The IPCC ignores contrary evidence....


Should We Believe the Latest UN Climate Report?

The UN Climate Change panel is asserting—again—that humans are overheating the planet. Again, they have no evidence to support their claim—but they want the U.S. to cut its energy use by perhaps 80 percent just in case. Stabilizing greenhouse gases means no personal cars, no air-conditioning, no vacation travel. It’s a remarkably sweeping demand, given that the earth has warmed less than 1 degree C, over 150 years. This on a planet where the ice cores and seabed sediments tell us the climate has been either warming abruptly or cooling suddenly for the past million years. The first long ice cores from Greenland and Antarctic were brought up in the 1980s. The ice layers showed the earth warming 1–2 degrees roughly every 1,500 years—usually suddenly. The natural warmings often gained half their total strength in a few decades, then waffled erratically for centuries—rather like our planet’s temperature pattern since 1850. History tells us the coolings, not the warmings, have been the bad part. After the Medieval Warming ended about 1300, Europe was hit by huge storms, gigantic sea floods, crop failures, and plagues of disease. My big gripe with the IPCC is that they’re still keeping this climate cycle a virtual secret from the public. What does the IPCC say about hundreds of long-dead trees on California’s Whitewing Mountain that tell us the earth was 3.2 degrees C warmer in the year 1350 than today? In that year, seven different tree species were killed—while growing above today’s tree line—by a volcanic explosion. The trees’ growth rings, species and location confirm that the climate was much warmer that of today, says C. I. Millar of the U.S. Forest Service, reporting in Quaternary Research, Nov. 27, 2006....


Climate Bills Are Self-defeating

Will 2007 be the year that the U.S. signs up for global warming regulation? After looking at the five climate bills being considered so far in the 110th Congress, I’m not so sure it will be. A bill drafted by Senate Energy Committee chairman Jeff Bingaman, D-N.M., is the most economically palatable bill and seems to have the most interest on Capitol Hill. But it would likely accomplish little in terms of reducing greenhouse gas emissions -- the ostensible purpose of global warming regulation. Bingaman’s bill calls for reductions in the intensity of greenhouse gas emissions by 2.6 percent per year from 2012-2021 and by 3.0 percent per year starting in 2022. Bingaman’s focus on reducing emissions intensity – rather than reducing absolute emissions of greenhouse gases – is what sets it apart from the other climate bills, which are all geared toward reducing total emissions. What’s the difference between reducing “emissions intensity” and total or absolute emissions? Conceptually, reducing absolute emissions is relatively straightforward. The goal would be to simply cut greenhouse gas emissions by specified amounts. Despite its apparent simplicity, emissions reduction is complicated by the fact that there is no general agreement as to how to measure greenhouse gas emissions in the first place. So far, emissions have been generally guess-timated based on energy production and/or use levels for a limited number of sources. Emission cuts also do not take into consideration the likely economic impacts of any attendant reductions in energy use. Emissions intensity, by contrast, attempts to relate emissions to economic productivity. Let’s say, for example, that a company’s total amount of greenhouse gas emissions doubled from 2000 to 2005. If over the same period of time its economic output also doubled, then the company’s emissions intensity remained constant. But if the company’s economic productivity had quadrupled, then its emissions intensity would have been cut in half. Emissions intensity, then, is a measure of efficiency, where the goal is higher economic output per unit of greenhouse gas emissions....


ARE POLAR BEARS VICTIMS?

Polar bear populations are decreasing in the southern Beaufort Sea region of Alaska and the western and southern Hudson Bay in Canada. As a result, the U.S. Fish and Wildlife

Service accepted a proposal last December to designate polar bears as a threatened species under the Endangered Species Act, says Scienceline.

Some prominent researchers suspect that changes in the climate are a leading threat to polar bear survival. Polar bears are especially vulnerable to rising Arctic temperatures because they hunt, mate and usually make their dens on sea ice. "There is no evidence they can survive on land without sea ice," says environmentalist Deborah Williams.

But, not everyone is convinced:

* Mitchell Taylor, a polar bear researcher for the Canadian province of Nunavut, has submitted a petition to the U.S. Fish and Wildlife Service opposing listing polar bears as threatened, stating that only two populations of bears are decreasing.
* H. Sterling Burnett, a senior fellow from the National Center for Policy Analysis noted the overall polar bear population has rebounded from about 10,000 to 20,000 and asserted that warm temperatures in the 1930s were similar to current conditions, yet polar bears survived then.

Those that see the general rise in polar bear population dislike the possibility of regulation for a species they feel doesn't need it. "The law doesn't say to look at any possible future threat. It says look at the data…if it's not endangered then it's not endangered," said Burnett. What counts is the number of polar bears that exist right now, not some possible decrease in the future.

Source: Emily V. Driscoll, "Are Polar Bears Victims of the New Cold War?" Scienceline, February 5, 2007.

For text:http://scienceline.org/2007/02/05/health_driscoll_polarbears/



Chicken Little and global warming

YOU KNOW that big United Nations report on global warming that appeared last week amid so much media sound and fury? Here's a flash: It wasn't the big, new United Nations report on global warming. Oddly enough, most of the news coverage neglected to mention that the document released on Feb. 2 by the UN's Intergovernmental Panel on Climate Change was not the latest multiyear assessment report, which will run to something like 1,500 pages when it is released in May. It was only the 21-page "Summary for Policymakers," a document written chiefly by government bureaucrats -- not scientists -- and intended to shape public opinion. Perhaps the summary will turn out to be a faithful reflection of the scientists' conclusions, but it wouldn't be the first time if it doesn't. In years past, scientists contributing to IPCC assessment reports have protested that the policymakers' summary distorted their findings -- for example, by presenting as unambiguous what were actually only tentative conclusions about human involvement in global warming. This time around, the summary is even more confident: It declares it "unequivocal" that the Earth has warmed over the past century and "very likely" -- meaning more than 90 percent certain -- that human activity is the cause. That climate change is taking place no one doubts; the Earth's climate is always in flux. But is it really so clear-cut that the current warming, which amounts to less than 1 degree Celsius over the past century, is anthropogenic? Or that continued warming will lead to the meteorological chaos and massive deaths that alarmists predict? It is to the media. By and large they relay only the apocalyptic view: Either we embark on a radical program to slash carbon-dioxide emissions -- that is, to arrest economic growth -- or we are doomed, as NBC's Matt Lauer put it last week, to "what literally could be the end of the world as we know it." Perhaps the Chicken Littles are right and the sky really is falling, but that opinion is hardly unanimous. There are quite a few skeptical scientists, including eminent climatologists, who doubt the end-of-the-world scenario. Why don't journalists spend more time covering all sides of the debate instead of just parroting the scaremongers?...