Large-Scale Climatic Controls on Lake Baikal Ice Cover

Abstract

Abstract Long-term records of winter ice duration, formation, and breakup dates (1869–1996) and maximum thickness (1950–95) on Lake Baikal are analyzed to determine the nature of temporal trends and the relationship with the large-scale atmospheric circulation. There are highly significant trends of decreasing ice duration (and thickness) over the period, associated with later ice formation and earlier breakup dates. These trends are broadly in line with those of winter air temperatures in the region. Variability in Lake Baikal ice formation date, duration, and thickness is significantly related to winter temperatures over a wide area from the Caspian Sea to the Pacific and from northern India to the Kara Sea off the northern coast of Siberia. Thus, Lake Baikal ice cover is a robust indicator of continental-scale winter climate. Correlation and composite analysis of surface and upper-atmospheric fields reveal that interannual variability in ice cover is associated with a tripolar pattern of upper-level ge...