Ice cores from the St. Elias mountains, Yukon, Canada: Their significance for climate, atmospheric composition and volcanism in the north pacific region

Abstract

A major achievement in research supported by the Kluane Lake Research Station was the recovery, in 2001-02, of a suite of cores from the icefelds of the central St. Elias Mountains, Yukon, by teams of researchers from Canada, the United States, and Japan. This project led to the development of parallel, long (103-1 0 4 year) ice-core records of climate and atmospheric change over an altitudinal range of more than 2 km, from the Eclipse Icefeld (3017 m) to the ice-covered plateau of Mt. Logan (5340 m). These efforts built on earlier work recovering single ice cores in this region. Comparison of these records has allowed for variations in climate and atmospheric composition to be linked with changes in the vertical structure and dynamics of the North Pacifc atmosphere, providing a unique perspective on these changes over the Holocene. Owing to their privileged location, cores from the St. Elias Icefelds also contain a remarkably detailed record of aerosols from various sources around or across the North Pacifc. In this paper we review major scientifc fndings from the study of St. Elias Mountain ice cores, focusing on fve main themes: (1) The record of stable water isotopes (δ18O, δD), which has unique characteristics that differ from those of Greenland, other Arctic ice cores, and even among sites in the St. Elias; (2) the snow accumulation history; (3) the record of pollen, biomass burning aerosol, and desert dust deposition; (4) the record of long-range air pollutant deposition (sulphate and lead); and (5) the record of paleo-volcanism. Our discussion draws on studies published since 2000, but based on older ice cores from the St. Elias Mountains obtained in 1980 and 1996. © The Arctic Institute of North America.