Hottest August in 174 years of records, says NOAA

Multiple heat records have been shattered this summer.

Last month was the hottest August ever recorded, according to National Oceanic and Atmospheric Administration records stretching back 174 years. The three-month period from June to August was also the hottest ever, the NOAA said on Thursday, and encompassed the hottest meteorological winter ever for the Southern Hemisphere.

Global sea surface temperatures were the highest for any August on record, and it was the fifth month in a row where global ocean sea surface temperatures set new highs for each respective month.

The sea surface temperature anomaly, or measurement of the departure from a long-term average, for August 2023 was also the largest anomaly on record.

Finally, sea ice extent in August hit a record low for all Augusts on record, 550,000 square miles below the previous record set in August 2019. Sea ice area is the total region covered by ice, while “extent” refers to the total region with at least 15 percent sea ice cover.

Global marine heat waves and the El Niño weather pattern contributed to all of extreme temperature records in 2023, Sarah Kapnick, the chief scientist at the NOAA, said in a statement released Thursday.

“But as long as emissions continue driving a steady march of background warming, we expect further records to be broken in the years to come,” Kapnick said.

The record temperatures for air and water contributed to extreme weather around the globe in August, including monsoon rains in Pakistan, India and Bangladesh. The NOAA summarized these events in the graphic embedded below.