Local variability of snow depth at different spatial scales in a Pyrenean basin

Snowpack properties can exhibit large spatial variability, even at very short distances. The degree of variability at various spatial scales must be considered in the estimation of areal-averaged snowpack properties, and over a specific area, to understand the main processes driving snow accumulation and melting. However, rarely there are high densities of snowpack measurements available to adequately analyse snow depth or SWE variability. This work analyses the spatial variability of snow depth at different spatial scales across a small (33ha) subalpine basin in the Spanish Pyrenees. Snow data were obtained using a Terrestial Laser Scanner (TLS) on five different days in the winter and spring of 2012. Scans provided accurate 0.5x0.5 m maps of snow depth, which allowed for the identification of changes at scales of 10, 25, 50 and 100 m2 during both the accumulation and melting seasons. Multiple regression techniques were used to identify the most influential topographical variable that explains the spatial variability of snow depth. The complexity of the terrain surface is the most important variable to explain the snowpack variability, but its effect changes depending on the snow depth, the spatial scale, and the time of the year.