Developing Synoptic Analogs for Extreme Mass Balance Conditions on Queen Elizabeth Island Ice Caps

Abstract

Detailed synoptic and climate analyses were undertaken for summer seasons during which extreme mass balance conditions were recorded on glaciers in the Queen Elizabeth Islands in high Arctic Canada. Three types of mass balance extremes were considered: 1) summer melt maxima; 2) suppression of summer melt; and 3) summer accumulation maxima. The following synoptic analogs were developed for these situations: 1) intrusion of a ridge into the Islands at all levels in the troposphere, and the consequent absence of the North American trough produces high melt and highly negative mass balance conditions; 2) maintenance of a deep cold trough across Ellesmere Island and down Baffin Bay with the resulting northwest flow off the Polar Ocean in the Queen Elizabeth Islands suppresses melt, and produces positive balance conditions on all Queen Elizabeth Island ice caps; and 3) tracking of surface and upper lows south and southeast across the islands from the Polar Ocean produces accumulation of snow in the summer and the most positive mass balance conditions in the record. These analogs can be applied to paleoclimatic problems.