Increased Snowfall

Much of the Arctic and Subarctic is dry, receiving at most 4 cm of annual precipitation on average, mostly in the form of snow. Precipitation has increased slightly over the last 40 years in the Mackenzie valley region in northwest Canada, with more increase in the north and less in the south. [5]

Caribou and muskox could be significantly affected if, as projected, snowfall continues to increase in the north. Herbivores can survive the long and frigid northern winters only by pawing through the snow to find food. Since the North is dry, there is normally not much snow to paw through (outside of local drifting). As a result, caribou and muskox can survive.

If, as projected, snowfall in the Arctic and Subarctic increases by 30 to 50 percent over the next few decades, herbivores may be forced to abandon large areas of winter habitat or spend much more energy searching for less food. As a result, much more pressure may be placed on populations. [6]

Warmer winters also often bring freezing rains and periodic thaws. A thick layer of ice can form that prevents feeding. This happened in the southwestern Queen Elizabeth Islands in the winter of 1973-4, when warm weather produced a sheet of ice so thick that 40 percent of the muskox and 65 percent of the Peary caribou starved to death. [7]