The new math on global warming
By Dennis T. Avery
The UN climate change panel told us in 2001 that human-emitted CO2 might drive the planet's average temperature upward by 5.8 degrees C -- a bigger average warming than the world has had in the past 100,000 years. The UN's 2007 report scales the possible overheating back a bit, to a maximum of 4.5 degrees -- still a very large warming.
But wait! The environmental movement is now conceding that the earth has a natural, moderate climate cycle. Jon Coifman of the Natural Resources Defense Council said recently on the Hannity and Colmes TV show, "The earth has natural temperature and climate cycles. Nobody has disputed that."
We're glad that the NRDC finally accepts the natural warming cycle as fact. Until Coifman's admission, I don't think the words "natural climate cycle" had ever escaped the lips of a climate alarmist.
The historic evidence of a moderate, natural 1,500-year climate cycle includes Roman writings, Egypt's early Nile flood records, and ancient Chinese court documents. The scientific evidence confirming the cycle has been literally "dug up" in the past 25 years, primarily from the oxygen isotopes in long, layered ice cores, and the one-celled fossils in the bottom sediments of lakes and oceans.
My favorite temperature proxy is North America's fossil pollen, which shows our continent has had nine complete shifts in its trees and plants over the past 14,000 years -- or one every 1650 years. In my native Michigan, the pollen says the forests during the warmings have been dominated by warmth-loving beech trees, with more oak trees intruding as the climate cools, followed by more pine trees. Today, 150 years into a warming, the pine trees are giving way again to the oaks, and the beech trees are waiting their turn.
Coifman is still talking about the planet passing a "crisis tipping point." He doesn't seem to realize that the existence of this natural cycle profoundly changes the math on global warming. The eco-movement and Al Gore have been repeating the mantra that "the earth has warmed 0.6 degree C in the last century." They claim this has been due to more human-emitted CO2, and project Big Warming on that basis. When we plug in the 1,500-year cycle, however, we have to take away from the scary computer models the 0.5 degrees of warming that occurred before 1940 -- and thus before much human-emitted CO2.
The earth has warmed only a net 0.2 degrees C of net warming since 1940. Human-emitted CO2 gets the blame for only half of that -- or 0.1 degree C of warming over 65 years! We've had no warming at all since 1998.
Remember, too, that each added unit of CO2 has less impact on the climate. The first 40 parts per million of human-emitted CO2 added to the atmosphere in the 1940s had as much climate impact as the next 360 ppm.
Why does NRDC say that the earth has reached a "crisis tipping point" when we've had only 0.2 degrees C of warming over the last 65 years -- and no warming at all over the past eight years? How do the Greens project a mind-numbing surge of global warming from this New Math on Global Warming?
Is the emerging evidence of the natural cycle the real crisis for Al Gore and the warming alarmists?
Dennis T. Avery was a senior policy analyst for the U.S. State Department, where he won the national intelligence medal of achievement. He is the co-author, with atmospheric physicist Fred Singer, of the book, Unstoppable Global Warming -- Every 1500 Years, available from Rowman & Littlefield. Readers may write him at the Center for Global Food Issues post Office Box 202, Churchville, VA 24421.