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Simulations of Future Snow Cover
The CCCma first generation global coupled model (CGCM1) has been used to produce climate simulations from 1900 to the present and projections from the present to the end of the next century. Plotted examples are shown below. The projections are based on a prescribed evolution of greenhouse gas and aerosol forcing (more details regarding this model and the experiments are available on the CCCma web site).
The figures show modelled snow water equivalent (in meters of water) computed as 20-year January to March averages for the periods: 1971-1990, 2041-2060, and 2081-2100. The first period represents 'present day' conditions, the second period represents the time of projected CO2 doubling relative to present day values, and the final period represents the last part of the 21st century. January to March was chosen as representing winter conditions in the northern hemisphere. One clearly sees a projected northward recession of the snowline in North America as the climate warms, a relatively larger change than is projected for eastern Eurasia.
Note on figures: Color bar indicates water equivalent depth in meters. Dark blue areas indicate permanent snow coverage on the ice sheets of Greenland and Antarctica.
Figure 1: Snow water equivalent (m) obtained from the CCCma Coupled Global Climate Model for March, averaged over years 1971-1990. 
Figure 2: Snow water equivalent (m) obtained from the CCCma Coupled Global Climate Model for March, averaged over years 2041-2060.  Figure 3: Snow water equivalent (m) obtained from the CCCma Coupled Global Climate Model for March, averaged over years 2081-2100.
Note that these results are obtained from one particular model using one particular scenario for future greenhouse gas and aerosol forcing. They are provided here as an example of projected changes in the cryosphere which might accompany changing climate.
Further Reading
- Flato, G.M., G.J. Boer, W.G. Lee, N.A. McFarlane, D. Ramsden, M.C. Reader, and A.J. Weaver. 2000: The Canadian Centre for Climate Modeling and Analysis Global Coupled Model and its Climate. Climate Dynamics , in press.
- Boer, G.J., G.M. Flato, M.C. Reader, and D. Ramsden. 2000a: A transient climate change simulation with greenhouse gas and aerosol forcing: experimental design and comparison with the instrumental record from the 20th century. Climate Dynamics, in press.
- Boer, G.J., G.M. Flato, and D. Ramsden. 2000b: A transient climate change simulation with greenhouse gas and aerosol forcing: projected climate change in the 21st century. Climate Dynamics, in press.
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