Comparative studies of glacier mass balance and their climatic implications in Svalbard, Northern Scandinavia, and Southern Norway

Abstract

On the basis of the data of glacier mass balance during 1946–2005 over Svalbard, Northern Scandinavia, and Southern Norway, the characteristics of glacier mass-balance are analyzed, and its sensitivity to climate change is calculated using a simple degree-day model. The mass balance of glaciers in these three regions reached maximum or comparatively high values in the late 1980s or the early 1990s. After that there was an accelerating negative tendency. A glacier with more positive mass balance has a higher sensitivity to equilibrium-line altitude (or climate) change and vice versa. On average, the mass loss during the entire period in these three regions was equivalent to the result of an air temperature rise of 0.32°C relative to zero net balance state. The highest temperature increase is found in Svalbard, and is 0.55°C; however, a rise of only 0.12°C is found in Southern Norway. The net balance sensitivity to a hypothetical air temperature increase of +1°C ranges from −0.31 to −1.03 m w.e. a−1, and the net balance sensitivity to an assumed increase in snow precipitation of +10% varies from +0.05 to +0.37 m w.e. a−1; thus, a 31% increase in snow precipitation is needed to compensate for the net mass loss induced by an air temperature increase of +1°C. The summer balance sensitivity to a hypothetical air temperature increase of +1°C varies from −0.39 to −0.95 m w.e. a−1, and the winter balance sensitivity to an assumed increase in snow precipitation of +10% ranges from +0.02 to +0.38 m w.e. a−1. This study confirms early findings that maritime glaciers have comparatively higher mass balance sensitivity than continental glaciers.