Articles | Volume 12, issue 4
The Cryosphere, 12, 1157–1176, 2018
The Cryosphere, 12, 1157–1176, 2018

Research article 04 Apr 2018

Research article | 04 Apr 2018

Canadian snow and sea ice: historical trends and projections

Lawrence R. Mudryk1, Chris Derksen1, Stephen Howell1, Fred Laliberté1, Chad Thackeray2, Reinel Sospedra-Alfonso3, Vincent Vionnet4, Paul J. Kushner5, and Ross Brown6 Lawrence R. Mudryk et al.
  • 1Climate Research Division, Environment and Climate Change Canada, Toronto, Canada
  • 2Department of Geography and Environmental Management, University of Waterloo, Waterloo, Canada
  • 3Climate Research Division, Environment and Climate Change Canada, Victoria, Canada
  • 4Centre National de Recherches Météorologiques, Centre d'Etudes de la Neige, Grenoble, France
  • 5Department of Physics, University of Toronto, Toronto, Canada
  • 6Climate Research Division, Environment and Climate Change Canada, Montréal, Canada

Abstract. The Canadian Sea Ice and Snow Evolution (CanSISE) Network is a climate research network focused on developing and applying state of the art observational data to advance dynamical prediction, projections, and understanding of seasonal snow cover and sea ice in Canada and the circumpolar Arctic. Here, we present an assessment from the CanSISE Network on trends in the historical record of snow cover (fraction, water equivalent) and sea ice (area, concentration, type, and thickness) across Canada. We also assess projected changes in snow cover and sea ice likely to occur by mid-century, as simulated by the Coupled Model Intercomparison Project Phase 5 (CMIP5) suite of Earth system models. The historical datasets show that the fraction of Canadian land and marine areas covered by snow and ice is decreasing over time, with seasonal and regional variability in the trends consistent with regional differences in surface temperature trends. In particular, summer sea ice cover has decreased significantly across nearly all Canadian marine regions, and the rate of multi-year ice loss in the Beaufort Sea and Canadian Arctic Archipelago has nearly doubled over the last 8 years. The multi-model consensus over the 2020–2050 period shows reductions in fall and spring snow cover fraction and sea ice concentration of 5–10 % per decade (or 15–30 % in total), with similar reductions in winter sea ice concentration in both Hudson Bay and eastern Canadian waters. Peak pre-melt terrestrial snow water equivalent reductions of up to 10 % per decade (30 % in total) are projected across southern Canada.

Short summary
This paper presents changes in both snow and sea ice that have occurred over Canada during the recent past and shows climate model estimates for future changes expected to occur by the year 2050. The historical changes of snow and sea ice are generally coherent and consistent with the regional history of temperature and precipitation changes. It is expected that snow and sea ice will continue to decrease in the future, declining by an additional 15–30 % from present day values by the year 2050.