Global Snow and Ice - November 2013
NH Snow Cover Extent
|November 2013||Snow Cover Extent||1981-2010 Anomaly||Trend
(out of 48 years)
|million km2||million mi2||million km2||million mi2||million km2||million mi2||Year(s)||million km2||million mi2|
Data Source: Global Snow Laboratory, Rutgers University. Period of record: 1966–2013 (48 years)
During November 2013, the Northern Hemisphere snow cover extent (SCE) was 34.76 million square km (13.42 million square miles), 800,000 square km (310,000 square miles) above the 1981-2010 average and the 16th largest November SCE in the 48-year period of record. This is the fifth consecutive November with above-average snow cover for the hemisphere. The autumn season (September-November) SCE was 1.84 million square km (710,000 square miles) above the 1981-2010 average and the sixth largest autumn SCE on record for the hemisphere. This was the fifth consecutive autumn with above-average SCE for the Northern Hemisphere and the largest autumn SCE since 2002.
The November North American snow cover extent was 14.76 million square km (5.70 million square miles), 1.28 million square km (500,000 square miles) above the 1981-2010 average and the third largest November SCE on record for the continent. During the month, the southern two-thirds of Canada, the Central and Northeastern U.S., and the Great Lakes region had above-average SCE. In fact, Canada had its largest November snow cover extent on record with 9.7 million square km (3.7 million square miles) of SCE, 1.0 million square km (390,000 million square miles) above average. Below-average SCE was observed in the American West, parts of the U.S. Central Plains, and far western Alaska. The contiguous U.S. also had above-average snow cover, while Alaska SCE was below average. For the autumn season, the North American SCE was 600,000 square km (230,000 square miles) above average and the seventh largest September-November SCE on record. This was the fourth consecutive autumn with above-average SCE and the largest SCE since 2002.
The Eurasian November SCE was 20.0 million square km (7.72 million square miles), 470,000 square km (180,000 square miles) above average. This was the 18th smallest November SCE and the smallest since 2008. Above-average SCE was observed across Scandinavia, the Tibetan Plateau, and far eastern China. Below-average SCE was present across much of Europe, western Russia, and Kazakhstan. The below-average SCE across Russia was related to temperatures more than 8°C above average in parts of the country. The autumn Eurasian SCE was 1.24 million square km (500,000 square miles) above average and the 10th largest on record, marking the fifth consecutive autumn with above average SCE and the largest seasonal SCE since 2002.
Sea Ice Extent
|November 2013||Sea Ice Extent||
(out of 35 years)
|million km2||million mi2||Year(s)||million km2||million mi2|
Data Source: National Snow and Ice Data Center (NSIDC). Period of record: 1979–2013 (35 years)
According to the National Snow and Ice Data Center (NSIDC), the Northern Hemisphere sea ice extent — which is measured from passive microwave instruments onboard NOAA satellites — averaged for November 2013 was 10.24 million square km (3.95 million square miles), 6.8 percent below the 1981-2010 average, and the sixth smallest November extent in the 35-year period of record. The Arctic sea ice extent grew at a near-average rate during November, gaining 74,800 square km (28,900 square miles) per day. The below-average Arctic average sea ice extent was driven in large part by the much-below-average sea ice in the Barents Sea. Most other regions of the Arctic had near-average sea ice coverage. November Arctic sea ice extent is decreasing at an average rate of 4.6 percent per decade.
The November 2013 Southern Hemisphere sea ice extent was 17.16 million square km (6.63 million square miles), 5.3 percent above average, and the largest November Antarctic sea ice extent on record. This marked the fourth consecutive month that the Antarctic sea ice extent was record large. The previous record large November Southern Hemisphere sea ice extent occurred in 2010 when the monthly extent was 16.94 million square km (6.54 million square miles). November Southern Hemisphere sea ice extent is increasing at an average rate of 0.9 percent per decade, with substantial interannual variability.
When combining the Northern Hemisphere and Southern Hemisphere sea ice extents, the globally-averaged sea ice extent during November was 27.40 million square km (10.58 million square miles), 0.4 percent above the 1981-2010 average and the 12th largest November global sea ice extent on record. This marked the first November since 1999 with above-average global sea ice extent and the largest November sea ice extent since 1994.
For further information on the Northern and Southern Hemisphere snow and ice conditions, please visit the NSIDC News page.