The Influence of an Arctic Large-Lakes System on Mesoclimate in South-Central Baffin Island, N.W.T., Canada

Abstract

Investigations in the interior lowlands of south-central Baffin Island have confirmed the existence there of a relatively warm, mesoscale summer climate compared to regional averages, an observation that is supported by the presence of certain low arctic plants beyond their previously reported limits. A system of two large lakes, their drainage basins, and tributaries is seen to be a major factor responsible for these conditions. Measurements made at Burwash Bay, where the Amadjuak River enters Nettilling Lake, provide the basis for heat budget estimates in the summer period. An average daily heat input of 22 MJ m^–2 d^–1 to the surface of the bay results in a late-season average temperature of the water column that is close to the average daily air temperature for July, which was 11°C in 1985 and 9°C in 1986. It is concluded that this heat reservoir acts to maintain locally moderate temperatures during times of cold air intrusion in summer and to retard the seasonal cooling in fall and early winter.