So how come Alaska's glaciers are growing?
By Dennis T. Avery
MichNews.com
Oct 28, 2008
Alaska’s glaciers grew this year, after shrinking for most of the last 200 years. The reason? Global temperatures dropped over the past 18 months. The global mean annual temperature has been declining recently because the solar wind thrown out by the sun has retreated to its smallest extent in at least 50 years. This temperature downturn was not predicted by the global computer models, but had been predicted by the sunspot index since 2000.
The solar wind normally protects the earth from 90 percent of the high-energy cosmic rays that flash constantly through the universe. Henrik Svensmark at the Danish Space Research Institute has demonstrated that when more cosmic rays hit the earth, they create more of the low, wet clouds that deflect heat back into outer space. Thus the earth’s recent cooling.
Unusually large amounts of Alaskan snow last winter were followed by unusually chilly temperatures there this summer. “In general, the weather this summer was the worst I have seen in at least 20 years,” says Bruce Molnia of the U.S. Geological Survey, and author of The Glaciers of Alaska. “It’s been a long time on most glaciers where they’ve actually had positive mass balance (added thickness).”
Overall, Molnia figures Alaska had lost 10–12,000 square kilometers of ice since 1800, the depths of the Little Ice Age. That’s enough ice to cover the state of Connecticut. Climate alarmists claim all the glaciers might disappear soon, but they haven’t looked at the long-term evidence of the 1,500-year Dansgaard-Oeschger climate cycles. During the Little Ice Age—1400 to 1850—Muir Glacier filled the whole of Glacier Bay. Since then, the glacier has retreated 57 miles. But the Little Ice Age was preceded by the Medieval Warming, the cold Dark Ages, a Roman Warming, and a whole series of moderate warmings and coolings that extend back at least 1 million years based on the evidence of the microfossils in the world’s seabed sediments.
The real question is whether today’s warming is different than the previous Dansgaard-Osechger warming cycles. I think that the difference, if any, is slight. Most of our Modern Warming occurred before 1940 and virtually all of our human-emitted CO2 came after that date. The temperatures in 1998—the recent peak—were only 0.2 degree C higher than in 1940. After the temperature drop of the past 18 months, the temperatures are now cooler than in 1940.
The 1,500-year cycles usually start with a sudden shift of 1–2 degrees—in temperate zones—and double that in Alaska. Then temperatures erratically rise and fall with the sun’s total irradiance changes, often in 11-year cycles. At the end of the warming, comes another Little Ice Age; or, every 100,000 years, a Big Ice Age that will drop temperatures about 15 degree C. That’s when insulation will truly become the most important invention in history.
The sunspots are now predicting a 30-year cooling of the earth. That would thicken the Alaskan glaciers somewhat, but probably wouldn’t refill Glacier Bay with ice. That’ll have to wait for the next icy age.
The sunspot index has a 59 percent correlation with our temperatures (with a roughly ten-year lag). CO2 has only an “accidental” 22 percent correlation with our temperatures, which should be grounds for dismissing CO2 as a major climate player.
All this is radically different from the 5-degree C warming predicted by the computer models. However, the scientific rule says: if actual observations tell you something that’s the opposite of your theory, change your theory.
DENNIS T. AVERY is a senior fellow for the Hudson Institute in Washington, DC and is the Director for the Center for Global Food Issues. (www.cgfi.org) He was formerly a senior analyst for the Department of State. He is co-author, with S. Fred Singer, of Unstoppable Global Warming Every 1500 Hundred Years.
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