This letter was sent to Rock and Ice's "Letters to the Editor" in response to Colin Wells' February 2006 story on the effect that Global Warming is having on mountaineering.

Thank you for publishing Colin Wells' fascinating and informative "Hot Damned" article. The dramatic photos and accounts of melting mountains add to the growing body of evidence for human-caused climate change.

I've been studying the causes and effects of global warming since the early '70s, long before it was fashionable to worry about it. Although most of what Colin concludes in his story is correct, he is wrong about a couple of crucial points: that we can reverse the trend by following the recommendations in the "Think Globally, Act Locally" section, and that combustion of fossil fuels is the primary factor behind human-caused climate change.

William F. Ruddmann's March 2005 Scientific American article "How Did Humans First Alter Global Climate?” presents the compelling case that our ancient agrarian ancestors initiated the increase in atmospheric greenhouse gases. Recent evidence shows that CO2 levels started rising as a result of agriculture about 8,000 years ago, just when natural trends called for those levels to fall. About 3,000 years later methane levels also started to rise. These changes occurred when the Earth was due to enter the next ice age, which would have devastated budding human civilization. Instead, the Earth's climate remained relatively warm and stable. (For the last several million years, ice ages, not the relatively short warm periods between them, have been the norm.)

Although it is clear that the last 200 years of industrial society have accelerated the rise of CO2 and CH4, as far back as the early 80's many scientists realized that we already passed a crucial "tipping point". The Earth has warmed enough so that decomposing vegetation in rain forests and melting arctic peat bogs will release nearly 100 billion metric tons of CO2 and CH4, even if all human activity on the planet were to cease today.

The millions of tons that we would save by driving less, flying less, turning off appliances, etc. are tiny compared to the amount that will be released from decaying vegetation. And that 100 billion tons, in turn, represents only 1/30th of the 2.7 trillion tons of CO2 in the atmosphere.

Don't get me wrong – wasting energy is moronic; I own a Corolla, which enables me to afford the 35,000 miles a year that I spend on the road driving to Hueco and other crags. It's stupid to waste precious hydrocarbons as a mere energy source – they are far more useful for manufacturing. I turn off my lights (most of which are fluorescent) when I'm not using them. I never fly when driving is a feasible alternative. But, I do those things because they make economic sense, sans altruistic fantasies that I am saving the planet.

Global warming is a reality and it is here to stay. I'm sad about the retreating glaciers; I grew up in Anchorage and remember being able to practice ice climbing on icebergs at the Portage Glacier parking lot. But, climbers must face reality and do what humans do best – adapt to changing conditions and learn to enjoy mountains that will have less and less ice and snow. Who knows - perhaps younger readers will someday make shirtsleeve ascents of Denali or the Compressor Route!

Steve Crye

Some references, in case anyone is interested:

Roger Revelle, "Carbon Dioxide and World Climate," Scientific American (August 1982).

P. Cloud, "The Biosphere," Scientific American, 249:176-189 (1983).

James F. Kasting, Owen B. Toon, James B. Pollack, "How Climate evolved on terrestrial planets," Scientific American, (February 1988).

Richard A Houghton, George M. Woodwell, "Global Climatic Change," Scientific American (April 1989).

Stephen H. Schneider, "The Changing Climate," Scientific American (September 1989).

C. Covey, "The Earth's Orbit and the Ice Ages," Scientific American, 263:58-66 (1990).

W. S. Broecker and G. H. Denton, "What Drives Glacial Cycles?" Scientific American, 263:49-56 (1990).

J. H. Ausubel, "A Second Look at the Impacts of Climate Change," American Scientist, 79:210-221 (1991).

W. F. Ruddiman and J. E. Kutzbach, "Plateau Uplift and Climatic Change," Scientific American, 66-75 (1991).

W. S. Broecker, "Chaotic Climate," Scientific American, 62-68 (1995).

http://www.newscientist.com/channel/earth/climate-change/mg18725124.500