Global Snow and Ice - November 2016
Beginning in November 2017, NCEI will use version 3 of the National Snow and Ice Data Center's (NSIDC) monthly sea ice extent index. All historical monthly sea ice extent values will be updated to version 3, but historical reports will not be updated. For additional information on the methodology changes and comparisons to version 2, please visit the National Snow and Ice Data Center.
NH Snow Cover Extent
|November 2016||Snow Cover Extent||1981-2010 Anomaly||Trend
(out of 51 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: 1966–2016 (51 years)
The Northern Hemisphere snow sover extent (SCE) for November 2016 was 36.93 million square km (14.26 million square miles), which is 2.97 million square km (1.15 million square miles), or 8.7 percent, larger than the 1981-2010 average. This tied November 2011 as the fourth largest November SCE in the 49-year period of record for the Northern Hemisphere. Each of the last eight Novembers, beginning with November 2009, has seen above-average Northern Hemisphere SCE values. November's long term trend (since 1967) is 360,000 square km (140,000 square miles) more SCE per decade.
The November North American SCE was 12.89 million square km (4.98 million square miles), which was 590,000 million square km (230,000 square miles) above average and the 12th smallest on record. Snow cover was below average over much of the continent, coinciding with unseasonably warm conditions in southern Canada and the northern United States.
The Eurasian SCE during November was 24.03 million square km (9.28 million square miles), which is 3.56 million square km (1.38 million square miles) above average. This was the second largest November SCE on record for Eurasia, only 10,000 square km (4,000 square miles) smaller than 1993. Above-average SCE dominated Eurasia, particularly in both European and Asian Russia, coinciding with a cold November, and following a cold October in much of the region.
Sea Ice Extent
|November 2016||Sea Ice Extent||
(out of 38 years)
|million km2||million mi2||Year(s)||million km2||million mi2|
Data Source: National Snow and Ice Data Center (NSIDC). Period of record: 1979–2016 (38 years)
According to the National Snow and Ice Data Center (NSIDC), the Northern Hemisphere (Arctic) sea ice extent — which is measured from passive microwave instruments onboard NOAA satellites — averaged for November 2016 was 9.08 million square km (3.51 million square miles), which was 1.95 million square km (750,000 square miles), or 17.7 percent, below the 1981-2010 average. This was the smallest November Arctic sea ice extent on record, and was 800,000 million square km (300,000 square miles) smaller than the previous smallest November Arctic sea ice extent in 2006. Basinwide, November sea ice extent grew at a slightly above average clip for the month as a whole, with a brief period of contraction - which is rare for this time of year - during the middle of the month. The sea ice extent deficits that developed during October were not overcome, and the entire month of November 2016 was spent at or below record small daily sea ice extent values.
New ice growth during November was most prominent in the Pacific side of the Arctic, which had the greatest seasonal deficits coming out of October 2016. Sea ice growth was anemic in the Barents Sea, north of Scandinavia. Detailed NSIDC analysis for the month.
The November Southern Hemisphere (Antarctic) sea ice extent was 14.54 million square km (5.61 million square miles), which was 1.81 million square km (700,000 square miles), or approximately 11.1 percent, below the 1981-2010 average. This was the smallest November Southern Hemisphere sea ice extent on record, one million square kilometers (400,000 square miles) smaller than the previous record-small November value set in 1986. Compared to the long-term average, the November 2016 sea ice "deficit" was more than double the size of the previous record. In the long term, Southern Hemisphere November sea ice extent is increasing at an average rate of approximately 0.4 percent per decade, with some inter-annual variability.
Like October 2016, November's day-to-day sea ice retreat was more rapid than the historical norms for the month. Roughly half way through the melt season, 2016 Antarctic sea ice extent is now more than two standard deviations smaller than the observations of 1981-2010.
For further information on the Northern and Southern Hemisphere snow and ice conditions, please visit the NSIDC News page.