Sea Ice | North Pole Observations | Glaciers | Snow Cover

See the annually updated Arctic Report Card essay on Terrestrial Snow!

The Arctic is generally snow covered in winter, so variations in snow cover extent actually occurs in the sub-Arctic more than in the Arctic. Snow cover area in Eurasia decreased in the early 1990s and during a cold event in 2003, but generally the observational record (based on satellite data) shows large year-to-year variability. Snow cover area in North America decreased from the late 1980s onward, again with much year-to-year variability. The twenty-four year trend in mean annual hemispheric snow extent indicates a decrease of approximately 4% per decade.

Eurasian Snow Cover Anomalies.From the Global Snow Lab at Rutgers University.		North American (except Greenland) Snow Cover Anomalies. From the Global Snow Lab at Rutgers University.

Time series of snow melt dates (as day of year) constructed for the NOAA ESRL GMD Barrow Observatory (BRW). Three linear regressions are plotted; an overall fit for 1941-2009 (black), one for all years prior to 1977 (green), and a third beginning in 1977 (red). The time series was compiled from direct snow depth observations, proxy estimates using daily temperature records, and beginning in 1986 on the basis of surface albedo measurements (Stone et al., 2002). The analysis updates that reported by Stone et al., (2005). The overall trend is quantified in the legend at the 95% confidence interval, and is obviously dominated by several years of early melt beginning in 1990.

Monthly snow (percent of days snow covered) on the land areas of the Northern Hemisphere during February 2012 (left) and May 2012 (right). From the Global Snow Lab , Rutgers University Climate Laboratory.