Ice Caps
Arctic sea ice decline happened faster than expected. This has the effect of accelerating global warming because less of the Sun's energy is reflected back into space by ice.
Northern Hemisphere snow also sends some of that energy back into space. The amount of snow cover we have is also declining.
Difference from average annual snow extent since 1971, compared to the 1966-2010 average (dashed line). Snow extents have largely been below-average since the late1980s. Graph adapted from Figure 1.1 (h) in the 2012 BAMS State of the Climate report.
The warming of the Arctic region is also…