Snow, landscape and people: Fieldwork in Sweden

Project Details

Method:

Snow depth and density were measured in the pre-snow melt period from March 24th to April 7th 2009. A transect between the ‘Abisko Birch’ (AB) and ‘Abisko Tundra’ (AT) research sites was surveyed with depth and density measured every 50 m using a snow tube and snow probe. Four additional depth measurements were made at each sampling point 2 m from the tube core location in N, S, E and W directions. At a research site between AB and AT named the ‘Intensive Valley’ (IV), snow depth was measured across a grid with 46 points at intervals of 25, 50 and 100m, and snow density was measured at 9 locations by digging snow pits. Higher resolution snow depth measurements were also taken along a 354 m transect in the IV (which included 3 snow pit locations), with snow depth sampled every 2 m.

The relationships between climate, vegetation, topography and snowcover were explored (see attached figure).

Summary and implications of findings:

In the pre-melt period of 2009, snow depth increases with vegetation height as reflected by the greater mean snow depth in forested areas where blowing snow is trapped. Density was greater in open areas where dense wind crusts form on the snow, and density decreases with vegetation height. Variations in these relationships are due to snow drifts of deeper, less dense snow forming in topographic hollows and sheltered lee slopes in the exposed open areas. Mean SWE was greater in forested areas, however there was not a significant relationship between SWE and vegetation height, likely because in the pre-melt period the greater depth in the forest is compensated for by lower densities. In the pre-melt period the snow depth and density variation isn’t significantly different between the forest and open areas. It is likely that this would change during the melt period when the open areas would melt earlier and at a greater rate thus resulting in patchy, more variable snow cover. There appears to be a clear differentiation in this pre-melt period between clearing and forest in terms of depth and density.

Less dense snow in the forested areas results in the winter transport routes concentrating in the open areas, as observed in the field. If a warming climate resulted in earlier snow melt, these transport routes would become unusable earlier in the spring, especially since many of them cross frozen lakes or marsh area. If this area was to be considered for farming and settlement in a warmer, less snow covered climate, proximity of farming sites to patches of birch forest would be an important consideration to optimise soil moisture and fresh water supply in the spring melt period.

Account Owner

School of Geosciences

University of Edinburgh

Drummond Street

Edinburgh

Project Collaborators