Terrestrial snow cover fraction and sea ice concentration seasonal trends for 1981–2015. Snow cover fraction is the proportion of time the ground is covered by snow. A decline of 10% per decade indicates a decline of approximately 3 days per month per decade in snow cover. Sea ice concentration is the percentage of area that is covered with sea ice. Stippling indicates statistical significance. Dashed line denotes limit of Canadian marine territory. From Chapter 5 Figure 5.2.