Sunday, September 14, 2008

Fixing Climate, Part 2

Phil Orr took Broecker to Pyramid Lake in Nevada, which is a remnant of Lake Lahontan, one of the largest lakes in North America during the last Ice Age. Orr had found human and animal bones in Fishbone Cave on the eastern shore of the dry bed of nearby Lake Winnemucca. Orr believed that man had entered North America during the Ice Age, and suspected that the bones dated to that time. In 1955, "scholars" favored a more recent date. Orr was interested in having Broecker perform carbon-14 dating on the human bones and artifacts that he had found. Broecker also took samples of tufa, a form of calcium carbonate, from Pyramid Lake. Broecker and Orr collaborated for the rest of the 1950s. Orr's intuition proved to be correct, and the rises and falls of the lakes in the Great Basin got Broecker interested in climate.