Huascaran δO as an indicator of tropical climate during the Last Glacial Maximum
نویسنده
چکیده
The interpretation of the isotopic composition of Andes tropical mountain glaciers is reconsidered using a simple Rayleigh distillation model. It is shown that Andes snowline depression and Huascaran ice core δO are consistent with a 3C drop in sea surface temperature during the Last Glacial Maximum, accompanied by an increase from 40% at present to 60% during the LGM in the annual mean proportion of atmospheric water lost to continental runoff. Broecker’s interpretation of Huascaran δO as a paleo-hygrometer is discussed.
منابع مشابه
Late glacial stage and holocene tropical ice core records from huascaran, peru.
Two ice cores from the col of Huascarán in the north-central Andes of Peru contain a paleoclimatic history extending well into the Wisconsinan (Würm) Glacial Stage and include evidence of the Younger Dryas cool phase. Glacial stage conditions at high elevations in the tropics appear to have been as much as 8 degrees to 12 degrees C cooler than today, the atmosphere contained about 200 times as ...
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