NOAA's National Centers for Environmental Information
Use the form below to select from a collection of monthly summaries recapping climate-related occurrences on both a global and national scale.
Global Snow and Ice ReportOctober 2019
NH Snow Cover Extent
The Northern Hemisphere snow cover extent for October 2019 was the fifth highest October extent since records began in 1967 at 22.26 million square km (8.59 million square miles). This value is 4.72 million square km (1.82 million square miles), or 26.89%, above the 1981–2010 average. October 2019 also marked the eighth consecutive October with above-average snow cover extent. October 2011 was the last time snow cover extent was slightly below average for the month. The largest Northern Hemisphere snow cover extent for the month of October occurred in 1976 with 25.72 million square km (9.93 million square miles), or 46.66%, above average.
The October North American snow cover extent was 9.49 million square km (3.66 million square miles). This was 1.44 million square km (560,000 square miles) above the 1981–2010 average and the third highest North American October snow cover extent in the 52-year record. Only Octobers 2002 and 2018 had a larger snow cover extent. October 2019 marked the eighth consecutive October with North American snow cover extent above average. North American snow cover was above average across much of central and southern Alaska, central and western Canada, and across the northern Rocky Mountains in the contiguous U.S. Below-average snow cover extent was limited to small areas across the western coast of Alaska, and parts of northeastern Canada. Canada's snow cover extent was the seventh highest October snow cover extent on record. The contiguous U.S. had its third largest October snow cover extent, while Alaska had its 18th largest on record.
Eurasia also had above-average snow cover extent during October 2019 at 12.05 million square km (4.65 million square miles), which is 990,000 square km (240,000 square miles) above average and the 11th largest October snow cover extent for Eurasia on record. This was also Eurasia's eighth consecutive October with above-average snow cover extent. Eurasia had above-average snow cover extent across much of Russia, northern Mongolia and Kazakhstan, as well as parts of southern China. Snow cover extent was below average across parts of northeastern Mongolia, and western and southern China.
Sea Ice Extent
The sea ice extent data for the Arctic and Antarctic is provided by the National Snow and Ice Data Center (NSIDC) and is measured from passive microwave instruments onboard NOAA Satellites. The sea ice extent period of record is from 1979–2019 for a total of 41 years.
The Northern Hemisphere Arctic sea ice extent was 5.66 million square km (2.19 million square miles), which is 2.69 million square km (1.04 million square miles), or 32.2 percent, below the 1981–2010 average. This was the smallest October sea ice extent in the 41-year record, surpassing the previous record set in 2012 by 230,000 square km (88,800 square miles). October 2019 marked the 19th consecutive year with Arctic sea ice extent below average. The ten smallest October Arctic sea ice extents have occurred since 2007. According to the NSIDC, the daily sea ice extent went from third lowest to the lowest daily extent during October 13–30. On 18 October 2019, the daily sea extent was 3.08 million square km (1.19 million square miles) below average—the largest daily departure from average on record. At the end of the month, the daily extent ranked as the second lowest, behind 2016. As the Northern Hemisphere enters the cool season, the Arctic begins its growth season. Sea ice extent grew along the coastal seas of Siberia. However, open water was still present across the Chukchi and Beaufort Seas due to above-average temperatures in the region. Of interest, the Chukchi Sea had its least sea ice extent on October 2019, exceeding the now second lowest October sea ice extent set in 2007.
For the fourth consecutive October, the Antarctic sea ice extent was below average. October 2019 Antarctic sea ice extent was 17.85 million square km (6.89 million square miles), giving way to the 10th smallest October Antarctic sea ice extent on record. This value is 250,000 square km (100,000 square miles), or 1.38 percent, below the 1981–2010 average.
