Is Global Cooling on the Way?

An article in the new New Scientist magazine claims that lower solar activity may lead to global cooling.

Dramatic global temperature fluctuations, as New Scientist reports, are the norm. A Little Ice Age struck Europe in the 17th century. New Yorkers once walked from Manhattan to Staten Island across a frozen harbour. About 200 years earlier, New Scientist reminds us, a sharp downturn in temperatures turned fertile Greenland into Arctic wasteland.

These and other temperature swings corresponded with changing solar activity. "It's a boom-bust system, and I expect a crash soon," says Nigel Weiss, a solar physicist at the University of Cambridge. Scientists cannot say precisely how big the coming cooling will be, but it could at minimum be enough to offset the current theoretical impact of man-made global warming. Sam Solanki, of the Max Planck Institute for Solar System Research in Germany, says declining solar activity could drop global temperatures by 0.2 degrees Celsius. "It might not sound like much," says New Scientist writer Stuart Clark, "but this temperature reversal would be as big as the most optimistic estimate of the results of restricting greenhouse-gas emissions until 2050 in line with the Kyoto protocol."

The New Scientist says this gives the Earth some breathing room in the face of climate change over the next 50 years, but it warns against complacency. "If the Earth does cool during the next sunspot crash and we do nothing [about man-made global warming], when the sun's magnetic activity returns, global warming will return with a vengeance," says Leif Svalgaard of Stanford University in California.

Well, that's one man's view based on his take on the science. But other scientists have differing views. Last month, the Russian Academy of Sciences' astronomical observatory reported that global cooling could develop in 50 years. Khabibullo Abdusamatov, head of the agency's space research branch, is reported to have said a period of global cooling similar to one seen in the late 17th century could start in 2012-2015 and reach its peak in 2055-2066. "The Kyoto initiatives to save the planet from the greenhouse effect should be put off until better times," he said.