NOAA: July 2021 was Earth’s warmest month in recorded history

INA - SOURCES 

July 2021 was Earth’s hottest July since global record-keeping began in 1880, 0.93 degrees Celsius (1.67°F) above the 20th-century average, NOAA’s National Centers for Environmental Information, NCEI, reported August 13. Since July is also the hottest month of the seasonal cycle, that meant that July 2021 was “more likely than not the warmest month on record for the globe since 1880,” NOAA said. 

July 2021 was just 0.01 degree Celsius hotter than July of 2016, 2019, and 2020, so these months can be considered to be in a statistical tie for Earth’s hottest month on record.

The record July warmth is particularly remarkable since there was a moderate La Niña event in the Eastern Pacific that peaked in November 2020 and ended in May 2021. La Niña events typically cause global cooling of about 0.1 degree Celsius; the peak cooling occurs five months after the La Niña peak, on average. 

July 2021 temperatures would have been even warmer had a La Niña event not occurred earlier this year.

NASA rated July 2021 the second warmest July on record, 1.16 degrees Celsius (2.09°F) above the 1880-1920 period, which is their best estimate of preindustrial temperature. 

The record warmest July in the NASA database is July 2019, which was 0.02 degree Celsius warmer than July 2021. Minor differences occur between the NOAA and NASA numbers because of how they handle data-sparse regions such as the Arctic.

The month’s exceptional heat was focused more on land areas than ocean areas, heightening its human impact: July 2021 global ocean temperatures were the sixth warmest on record, according to NOAA, while global land areas experienced their warmest July on record. 

Asia had its hottest July on record; Europe, its second hottest; North America, South America, Africa, and Oceania all had a top-10 warmest July.