Ice core drilling at King Col, Mount Logan 2002

Abstract

An ice core of 220.52 m was drilled at King Col (60°35' 20 N, 140°36' 15W; 4135m), a saddle near Mount Logan (5959 m), the Canada's highest mountain, in order to better understand 1) anthropogenic impact on the Pacific sector of the Arctic, 2) decadal and interdecadal climate changes in the North Pacific, and 3) dynamical behavior of cold mountain glaciers. The thickness of the glacier was estimated by an ice-penetrating radar survey at five points and the drilling site was decided at the flattest surface of which depth was calculated as 222 m. The recovered ice cores showed the site was located at dry snow zone with a very limited amount of melt-freeze ice layers. Temperature of the borehole was -18.0 °C at 10 m-depth and -17.7 °C at 220.52 m. The Nye time scale suggested that the ice core covers approximately several hundreds years to a millennium record of past climate and atmospheric proxy signals, provided annual accumulation rates from 0.4 to 1.0 m a -1 in ice.