Journal of Cave and Karst Studies - ISSN 1090-6924
Volume 66 Number 1: 20-27 - April 2004

A publication of the National Speleological Society

Holocene climatic variation recorded in a speleothem from McFail’s Cave, New York
Philip E. van Beynen, Henry P. Schwarcz, and Derek C. Ford

Abstract

A speleothem collected from McFail’s Cave, central New York, was analyzed in order to produce a high resolution paleoclimatic record for this region. The record is dated by Th/U ICP Mass Spectrometry. Variation in growth rates and d18O values for the period 0 to 7.6 ka revealed three distinct intervals: maximum warmth and wettest from 7.6 to 7.0 ka; a slow steady cooling from 7.0 to 2.5 ka; and fairly constant temperatures for the last few thousand years. The climatic optimum appears to have occurred at or before 7.6 ka. These changes are in agreement with regional stable isotopic and lake level records from the Finger Lakes in NY, suggesting the climatic changes are regional in scope. Enrichment of 18O in speleothem deposited at this time suggests that temperatures could potentially have been 5°C warmer than at present, which is consistent with pollen records for this region. However, a northward shift in the Jet Stream during the period would have affected the source area of the rainfall, providing heavier d18O values, an effect that would potentially reduce our temperature increase of 5°C. Quantification of this shift’s contribution to the temperature increase recorded by our speleothem is extremely difficult due to the lack of information about the exact location of the Jet Stream. d13C values are generally uniform but show a brief vegetational optimum at ~7.5 ka and increased density from 5.5 to 2.5 ka, suggesting a wetter climate.

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