Summer Snow Patches and Climate in Northeast Scotland, U.K.

Abstract

Numbers and lengths of snow patches above 600 m altitude in northeast Scotland were recorded in summer and autumn during the period 1974-1989, and were compared with regional climate in those years. The number of patches and their total length declined from July to October and varied between years. Only two patches survived through the study. Both number and total length were strongly related to winter and spring temperature and to amounts of snow-drift. Areal density of patches increased with altitude up to 1200 m but decreased sharply on the exposed hill tops above this altitude. The direction of snow-drift affected the distribution of patches among slopes of different aspect. Most patches faced northeast or southeast, the same aspect as most corries. In summer, the previous months' climate had little effect on the number or total length of patches in the following month, or on the rate of loss between months. Patch losses in most summers followed a negative exponential decay curve. Our results indicate that summer snow patches are a useful short-term integrative index of climate change. 21 refs., 6 figs., 7 tabs.