Estimating snow conditions in Finland in the late 21st century using the SNOWPACK model with regional climate scenario data as input

Abstract

An assessment of possible snow changes in a changing climate for Finland is presented. The snowpack structure model SNOWPACK (developed at the Swiss Federal Institute for Snow and Avalanche Research) was used for calculating snow conditions at six different locations in Finland for the decades 1980–89 and 2080–89. Regional climate model (RCAO) data from the Rossby Centre, Sweden, were used as input to the SNOWPACK model. Ten years from the RCAO control run and scenario run were chosen, and the snow conditions for different snow zones were calculated for these winters. The snow-cover depth and duration decreased at all locations in the scenario run cases, and the snow-cover quality also changed between the control and scenario runs: grains were bigger, snow was warmer and denser, and the fraction of faceted snow decreased while the fraction of icy or melting snow increased, even in mid-winter. Finally, the variability between different global climate predictions was analyzed. Significant differences were found between different climate-model outputs. The inter-model variability is comparable to the interannual variability of a single model. The qualitative conclusions from the scenario run do not critically depend on the climate-model variability.