October 2021 fourth-warmest on record: NOAA

NOAA – October 2021 ranked as the fourth-warmest October in 142 years, scientists at NOAA’s National Centers for Environmental Information announced on Nov. 15.

Looking at just land temperature, the Northern Hemisphere hit a new high and logged its warmest October on record.

Here are highlights from NOAA’s October global climate report:

Climate by the numbers

The average global land and ocean surface temperature in October was 0.89 of a degree Celsius above the 20th-century average of 14.0 degrees C, making it the fourth-warmest October in the global climate record.

The last eight Octobers (2014 to 2021) all rank among the eight warmest Octobers on record.

The unusual warmth across the Northern Hemisphere’s land area resulted in the warmest October land temperature on record. Meanwhile, North America had its second-warmest October on record, behind the record-warm October of 1963. South America had its third-warmest October, while Africa and Asia had their seventh- and 12th-warmest October on record, respectively.

Year to date | January through October

Globally, the YTD temperature (January through October) ranked as the sixth-warmest recorded, 0.84 of a degree C above the 20th-century average of 14.1 degrees C. The Northern Hemisphere’s YTD temperature was the sixth-warmest on record, while the Southern Hemisphere’s tied with 2010 and 2014 for eighth-warmest.

According to NCEI’s Global Annual Temperature Rankings Outlook, 2021 is on track to be among the 10 warmest years on record for the globe.

Other notable climate stats and facts

Sea ice coverage was sparse at both poles: According to the National Snow and Ice Data Center, the October 2021 Arctic sea ice extent (coverage) was 158,000 square kilometres below average, tying with 2017 as the eighth-smallest October extent in the 43-year record. Antarctic sea ice coverage last month was 466,200 sq. km. below average, ranking as the fourth-smallest October sea ice coverage on record. Only the Octobers of 1984, 1986, and 2016 had a smaller sea ice extent.

Tropical activity is running high in 2021: The total number of named global tropical storms for the YTD (Atlantic, Indian and Pacific basins) is 86, which is above normal for the first 10 months of the year. Although the Atlantic basin had relatively little tropical activity in October, the number of named storms tallied so far for the 2021 Atlantic hurricane season is 21, the third-highest number of named storms on record.