New study affirms natural climate change
By Dennis T. Avery
It's nice when people validate your work. Fred Singer and I—co-authors of Unstoppable Global Warming Every 1500 Years—are currently basking in the glow of a new paper that affirms the earth's long, moderate, natural climate cycle. The study is by Dr. U.R. Rao, former chair of India's Space Research Organization. He says solar variations and cosmic rays account for 40 percent of the world's recent global warming.
Dr. Rao says the data between 1960 and 2005 show lots fewer cosmic rays hitting the earth, due to a periodic expansion of the sun's magnetic field. The bigger solar magnetic field blocked many of the cosmic rays that would otherwise have hit earth. Fewer cosmic rays hitting the earth meant fewer water droplets shattering in our atmosphere, and thus fewer of the low, wet clouds that deflect solar heat back into space. So the earth warmed.
Fred and I tried to tell the world in 2007 that the moderate 1500-year Dansgaard-Oeschger cycle was the cause of the warming since 1850, based on historic and paleoclimatic evidence. The cosmic ray linkage was put forth in 2008 by Henrik Svensmark of Denmark. The UN's panel on climate change dismissed that whole approach, claiming the variations in the sun's irradiance were far too small to account for the rapid warming from 1976–98.
The flaw in the UN reasoning is clear, however. The alarmists claim the global warming since 1976 has been too rapid to be caused by natural forces, and therefore must be man-made. However, the earth's Industrial Revolution went global after 1945—releasing the first big flush of CO2 emissions. That burst of greenhouse gases should have sharply boosted the earth's temperatures. Instead, the earth's temperature declined from 1940–75.
Commenting on Rao's paper, V. Ramanathan of the U.S.-based Scripps Institute of Oceanography says, "The observed rapid warming trends during the last 40 years cannot be accounted for by trends in [cosmic rays]." But didn't earth's warming from 1915–1940, too early to blame on CO2, move just about as fast for just about as long as the "unnatural" warming from 1976–98?
Did human greenhouse emissions account for the other 60 percent of our Modern Warming? Well, a modern city is fully capable of warming its own temperatures by 7 degrees C or more through expanded brick and blacktop and lost greenery. A huge number of rural weather stations have been dropped from the rolls in recent years, putting our thermometers still more heavily in debt to Urban Heat Islands.
A study by Dr. Eugenia Kalnay of the University of Maryland says 40 percent of our net temperature increase since 1940 was actually caused by expanding urban heat islands and land use changes. Since the official net warming over that period is only about 0.2 degree C, that doesn't leave much for Al Gore to deplore.
Nor do these studies offer much support for the EPA's recent finding that global warming presents "public endangerment." One of EPA's own senior scientists produced a contrary evaluation, but he's been retired and his paper has been ignored up by the government and the mass media.
India may be the most scientifically advanced country that refuses to agree the current global warming is man-made. Dr. Rao's paper has just been accepted by India's most prestigious science journal, Current Science.
Dennis T. Avery, an environmental economist, is a senior fellow at the Hudson Institute in Washington, DC. 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, Readers may write him at PO Box 202, Churchville, VA 24421 or email to firstname.lastname@example.org.