Number 156 (Story #2), December 17, 1993 by Phillip F. Schewe and Ben Stein|
DATA FROM TWO GREENLAND ICE PROJECTS DIFFER for the sections of ice deposited during the Eemian period, the last "interglacial" (warm) period prior to the current one. Representatives from the US-funded Greenland Ice Sheet Project 2 (GISP2) and the European- funded Greenland Ice-core Project (GRIP) discussed their results at the Fall Meeting of the American Geophysical Union in San Francisco. According to Willi Dansgaard of the University of Copenhagen, the GRIP ice core shows that temperatures during the Eemian fluctuated wildly, typically by 5-7 degrees Celsius over a matter of decades. This implies that the current interglacial period (the Holocene), is either unusually stable or is subject to the same fluctuations in climate. However, Ken Taylor of the University of Nevada reported that the GISP2 ice core does not exhibit these same fluctuations for the Eemian period. Both teams are trying to work out the discrepancy, which may have been caused by distortions in the ice. The data for the top 90% (2700 m) of the cores agree excellently, which the researchers believe will lead to a climate model of unprecedented accuracy stretching back to 100,000 years with "significantly better than bi-annual resolution," according to Paul Mayewski of the University of New Hampshire.