Reading Three: Land dwellers
Impact: Difficulty getting to food
Global warming has affected the winter temperature and precipitation in the Arctic. Precipitation that once fell as snow now increasingly falls as freezing rain. This freezing rain as well as increasingly-common freeze-thaw events (when the changing temperature rises above freezing and snow begins to melt and then falls below freezing and the water turns to ice), can cover plants in a layer of ice. Even if the plants can survive being covered in ice, animals have difficulty reaching the plants and can starve. Lemmings, musk ox and reindeer/caribou have all had large die-offs due to ice crusting making their food inaccessible.
Impact: Disintegration of shelter
Even though snow may seem cold to you, it provides much-needed insulation for small animals like lemmings and voles who live and find food in the space between the frozen ground and the snow. For them, the snow is a shelter from the cold winds and very cold air temperatures. Mild and wet winter weather can reduce the ability of the snow to provide insulation and can even make the under-snow spaces collapse. Some animals such as snowy owls, skuas, weasels and ermines hunt lemmings and voles and almost nothing else. If numbers of lemmings and voles decline due to disintegration of their shelter, numbers of their predators will decline as well.