CR 53:1-12 (2012)  -  DOI: https://doi.org/10.3354/cr01090

ABSTRACT: Continuous measurements of both δD and δ¹⁸O were performed along a 108.8 m ice core recovered from the East Rongbuk Glacier on the northeast saddle of Mt. Qomolangma (Everest) (28.03°N, 86.96°E, 6518 m above sea level) in September 2002. They provide the first high-resolution historical record of deuterium excess (d) in the central Himalayas. In this paper, we focus on d variability from 1951 to 2001 and its relationship with large scale atmospheric circulation. The d record exhibits significant seasonal variations, with low values in summer and high values in winter, reflecting the atmospheric circulation shift between winter westerlies and the Indian summer monsoon (ISM). The interannual d variation is primarily controlled by the ISM moisture transport. An abnormally high d value during the period 1960–1964 is linked with the strengthening of winter westerlies, while an anomalously low d value during the period 1965–1968 is primarily a result of the migration of the ISM moisture source region, and secondly of surface sublimation. The results show that the ice-core d record retrieved from the high Himalayas is a good proxy for changes in atmospheric circulation.

KEY WORDS: Himalayas · Ice core · Deuterium excess · Atmospheric circulation