Climate Change – Evidence from High Altitude
Thin Ice: Unlocking the Secrets of Climate in the World’s Highest Mountains, Mark Bowen 2005
One of the best books on global warming comes thinly disguised as a mountain climbing adventure book. Scientist Lonnie Thompson has spent over thirty years climbing some of the highest mountains in the world to collect fast disappearing ice core samples. In the process he has incidentally set a record for the most time spent over a lifetime in the death zone. To get some idea what this means, see Anatoli Boukreev.
The scientific importance of Thompson’s work is the collection and preservation of ice cores, some possibly as old as 1 million years from places where they are fast disappearing due to the warming.
Thompson finds evidence of global warming and cooling cycles predicted by the earths orbit around the sun. The period of these shifts are related to changes in the tilt of Earth’s rotational axis (41,000 years), changes in the orientation of Earth’s elliptical orbit around the sun, called the “precession of the equinoxes” (21,000 years), and to changes in the shape (more round or less round) of the elliptical orbit (96,000 years). We are presently nearing the top of a warming phase where temperature would be expected to rise, but the levels of CO2 in the atmosphere is far higher than anything ever experienced in the last million years.
Thompson noticed in the Andes samples evidence of changes every 400 years or so. When he consulted with anthropologists he discovered that the time of these changes corresponds to the rise and fall of local civilizations throughout Latin America. The falls were usually very quick and sometimes initiated by a catastrophic weather event such as a massively destructive flood. Thompson was able to pinpoint in time and find evidence in the ice cores of these catastrophic events. These changes are believed to be related to changes in Pacific Ocean temperatures and ocean current patterns resulting in American rain belts being turned into desserts and vice versa. Thompson believes this change is currently happening in the American West where snow and ice are fast disappearing from the Cascades and Sierras.
The book talks about the ultimate failure of every large scale irrigation system throughout history when weather patterns change, usually removing the ice and snow that feeds these projects. The California Central Valley may soon become dessert again.
Click on Lonnie Thompson Video
Many of Thompson’s findings are presented in Al Gore’s An Inconvenient Truth.