Assessing the Global Climate in January 2021

The globally averaged temperature departure from average over land and ocean surfaces for January 2021 was the seventh highest for the month of January in the 142-year NOAA record, which dates back to 1880.

This monthly summary, developed by scientists at NOAA National Centers for Environmental Information, is part of the suite of climate services NOAA provides to government, business, academia and the public to support informed decision-making. 

January 2021

The January 2021 global land and ocean surface temperature was the seventh highest in the 142-year record at 1.44°F (0.80°C) above the 20th-century average of 53.6°F (12.0°C). 

• January 2021 marked the 45th consecutive January and the 433rd consecutive month with temperatures, at least nominally, above the 20th-century average.
• The year began with a La Niña episode in the tropical Pacific Ocean that started in August 2020. The El Niño-Southern Oscillation (ENSO) can affect global temperatures. La Niña tends to cool slightly global temperatures, while El Niño tends to boost global temperatures. 
• The Northern Hemisphere January 2021 temperature departure of 2.03°F (1.13°C) tied with 2019 as the fifth highest on record. The Southern Hemisphere’s temperature departure was 0.83°F (0.46°C) above average -- the smallest departure for January since 2012.
• Temperatures were at least 4.5°F (2.5°C) above average over much of northern North America, northern Africa, southeastern Europe, and parts of the Middle East. Parts of the North and South Pacific Ocean and the northwestern Atlantic Ocean (off the U.S. Northeast coast) also had notable warm temperature departures of at least 3.6°F (2.0°C) above average. Meanwhile, much of northern Asia was at least 3.6°F (2.0°C) below average, in stark contrast to most of 2020, when the region was well above average. Additionally, cooler-than-average conditions were present across the central and eastern tropical Pacific Ocean, consistent with La Niña conditions, as well as the southeastern Pacific Ocean and the northern Atlantic Ocean (off the coast of Greenland).  
• Africa and North America had their warmest and second-warmest January, respectively, since regional records began in 1910. 
• According to a statistical analysis done by NCEI scientists, 2021 is very likely to rank among the 10 warmest years on record. There is only 2.9% chance of 2021 ending as the warmest year on record.

Sea Ice and Snow Cover

• The January Arctic sea ice extent was 5.20 million square miles, which is 363,000 square miles (6.5 percent) below the 1981–2010 average and the sixth-smallest January extent in the 43-year record, according to an analysis by the National Snow and Ice Data Center using data from NOAA and NASA. Baffin Bay had its second-smallest sea ice extent on record, behind January 2011. Arctic sea ice over the Barents, Bering, Greenland, and Kara seas as well as the Sea of Japan were below average.
• The average January Antarctic sea ice extent was 1.80 million square miles, which is 130,000 square miles (6.6 percent) below the 1981–2010 average and tied with 2007 as the 13th-smallest January sea ice extent on record. January 2021 marked the sixth consecutive January with Antarctic sea ice extent below average. 
• According to data from NOAA and analyzed by the Rutgers Global Snow Lab, the Northern Hemisphere snow cover extent during January was near average. The North American snow cover extent was slightly above average, while Eurasia had a slightly below-average extent for the month.

For a more complete summary of climate conditions and events, see our January 2021 Global Climate Report.