Is the debate now over for skeptics of global warming hysteria? Readers of USA Today may certainly have that impression.
“Satellite and weather-balloon research released today removes a last bastion of scientific doubt about global warming, researchers say,” reported USA Today on Aug.12.
Certainly the USA Today report was partially correct – the researchers did, in fact, “say” [read “claim”] that “the last bastion of scientific doubt” had been removed. But claims and reality often don’t match up.
Three papers published in the journal Science last week purport to debunk an important argument advanced by skeptics of the notion of catastrophic, manmade global warming. The skeptics’ argument is that while temperatures measured on the Earth’s surface seem to indicate that global temperatures have increased at a rate of about 0.20 degrees Centigrade per decade (deg. C/decade) since the 1970s, temperatures measured in the atmosphere by satellite and weather balloons have shown only a relatively insignificant amount of warming for the same time period (about 0.09 deg. C/decade).
The implication of the skeptics’ argument is that whatever warming seems to be happening on the Earth’s surface, similar warming isn’t happening in the atmosphere. This might mean that any observed surface warming is more likely due to the urban heat island effect -- where the heat-retaining properties of concrete and asphalt in urban areas artificially increase local temperatures -- rather than increasing atmospheric levels of greenhouse gases like carbon dioxide.
One of the new Science studies reported that the satellites had drifted in orbit, causing errors in temperature measurement. Corrections to the satellite data, according to the researchers, would increase the atmospheric warming estimate to 0.19 deg. C/decade -- more in line with the 0.20 deg. C/decade warming of the Earth’s surface. Another study reported that heating from tropical sunlight had skewed the balloon temperature measurements.
Ben Santer of the Lawrence Livermore National Laboratory, one of the studies’ authors, told USA Today that, “Once corrected, the satellite and balloon temperatures align with other surface and upper atmosphere measures, as well as climate change models.”
So is it really game-set-match in favor of the global warming alarmists? Not so fast, say the skeptics.
When University of Alabama-Huntsville researcher Roy Spencer, a prominent climatologist, factored the newly reported corrections into his calculations, his estimate of atmospheric warming was only 0.12 deg. C/decade -- higher than the prior estimate of 0.09 deg. C/decade, but well below the Science study estimate of 0.19 deg C/decade and the surface temperature estimate of 0.20 deg. C/decade.
As to the claimed errors in the weather balloon measurements, Spencer says that no other effort to adjust the balloon data has produced warming estimates as high as those reported in the new study and that it will take time for the research community to form opinions about whether the new adjustments advocated are justified.
Climate expert Dr. Fred Singer of the Science and Environmental Policy Project says the temperature adjustments are “not a big deal.”
“Greenhouse theory says (and the models calculate) that the atmospheric trend should be 30 percent greater than the surface trend -- and it isn’t,” says Singer. “Furthermore, the models predict that polar [temperature] trends should greatly exceed the tropical values -- and they clearly don’t ... In fact, the Antarctic has been cooling,” adds Singer.
Singer also had some related thoughts concerning the gloom-and-doom forecasts concerning future temperatures.
Last January, a study in the journal Nature estimated that a doubling of atmospheric levels of carbon dioxide would increase global temperatures anywhere from 1.9 degrees Centigrade to 11.5 degrees Centigrade by mid-century. But Singer says the researchers “varied only six out of many more parameters necessary to model clouds… Their result confirms… that clouds are still too difficult to model and that climate models underlying the Kyoto Protocol have never been validated.”
So it’s far from “case-closed” on global warming skepticism. Moreover, aside from the controversy over the satellite and weather balloon data, many key climate questions remain unanswered including: whether humans are causing significant warming; whether warming is undesirable; and whether anything be done to avert any undesirable warming.
Because of its prohibitive costs, alarm over global warming has been rejected numerous times by President Bush and the U.S. Senate. European nations are already discovering that their economies can’t live with the Kyoto Protocol that was just implemented in February.
Despite alarmist media reports, global warming-mania is melting. It’s no wonder the alarmists are in such a hurry to close the book on the science.
Steven Milloy publishes JunkScience.com and CSRwatch.com, is adjunct scholar at the Competitive Enterprise Institute, and is the author of Junk Science Judo: Self-defense Against Health Scares and Scams (Cato Institute, 2001).