Alaska Science Forum
May 28, 2009Cooler decades ahead, researcher says
Article #1961
by Ned Rozell
This column is provided as a public service by the Geophysical Institute, University of Alaska Fairbanks, in cooperation with the UAF research community. Ned Rozell is a science writer at the institute.
Syun-Ichi Akasofu has a forecast for the average global temperature during the next few decades—cool. Akasofu, who gave a recent presentation on his ideas in Fairbanks, bases his cooling prediction on his studies of climate records that go back several centuries, such as the breakup date of a lake in Japan that people have documented since the 1400s. He looks back to the distant past to try to see patterns of natural changes that have been occurring before levels of carbon dioxide in Earth’s atmosphere began skyrocketing after World War II. When he looks at long-term climate records, Akasofu sees a consistent warming since about 1800. For him, it’s as simple as drawing a straight line through the ups and downs of global temperature from 1800 to 2000. “This is why glaciers have been melting since about 1800,” he said. “Because the planet is still warming up from the Little Ice Age (a cold period from about 1400 to 1800). “The IPCC paid attention to only the latest temperature rise, from 1975 to 2000,” Akasofu said. “This is what I call ‘instant climatology.’ They didn’t look at the Little Ice Age. There’s no excuse for that.” Akasofu has a similar critique of scientists who compare photos of glaciers that have shrunken in the last decades—that it’s too brief a look at Earth’s climate. “It’s not the whole story,” he said. In trying to reconstruct the broader story, Akasofu has extended his straight line through temperature ups and downs from the year 1800 to the year 2100. Based on this, and including the roller-coaster ups and downs in world temperature trends some scientists call “multi-decadal oscillation,” Akasofu said that we have just crested the top of one of the warm peaks. He predicts that the average global temperature will continue to drop until about 2030. “In fact, world temperatures have already stopped rising, since 1998, which annoys the IPCC,” he said. He also pointed out that a similar change happened in 1940, when the Earth cooled until about 1975, a time when some scientists predicted a coming ice age. At the end of this century, in the year 2100, the average world temperature will be a few tenths of a degree warmer than the temperature now, Akasofu predicts. His view contradicts the most recent IPCC predictions of world temperatures rising by 3 to 6 degrees Celsius by 2100. Akasofu is no stranger to the role of contrarian. He has followed gut feelings throughout his career, such as the time he looked beyond an accepted idea about the aurora and came up with the theory of the aurora substorm, when the aurora bursts with activity more than once each night. Aurora scientists will remember him for that insight, and they still refer to his 1964 substorm paper as a classic. But how will climate scientists remember him—as someone who tried to oversimplify a complex equation, or as a visionary who saw something other people overlooked? Time, and temperature, will tell.
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