San Francisco Chronicle - (Sunday)

July sets unwelcome record for heat

- By Seth Borenstein Seth Borenstein is an Associated Press writer.

Earth sizzled in July and became the hottest month in 142 years of record-keeping, U.S. weather officials announced.

As extreme heat waves struck parts of the United States and Europe, the globe averaged 62.07 degrees last month, beating out the previous record set in July 2016 and tied again in 2019 and 2020. the National Oceanic and Atmospheri­c Administra­tion said. The margin was just .02 degrees.

The last seven Julys, from 2015 to 2021, have been the hottest seven Julys on record, said NOAA climatolog­ist Ahira Sanchez-Lugo. Last month was 1.67 degrees warmer than the 20th century average for the month.

“In this case, first place is the worst place to be,” NOAA Administra­tor Rick Spinrad said. “This new record adds to the disturbing and disruptive path that climate change has set for the globe.“

“This is climate change,” said Pennsylvan­ia State University climate scientist Michael Mann. “It is an exclamatio­n mark on a summer of unpreceden­ted heat, drought, wildfires and flooding.”

Last week, a prominent United Nations science panel warned of worsening climate change caused by the burning of coal, oil and natural gas and other human activity. Warming on land in western North America and in parts of Europe and Asia drove the record-setting heat, Sanchez-Lugo said. While the worldwide temperatur­e was barely higher than the record, what shattered it was land temperatur­e over the Northern Hemisphere, she said. Northern Hemisphere temperatur­es were a third of a degree higher than the previous record set in July 2012, which for temperatur­e records is “a wide margin,” SanchezLug­o said.

July is the hottest month of the year for the globe, so this is also the hottest month on record.

One factor helping the world bake this summer is a natural weather cycle called the Arctic Oscillatio­n, sort of a cousin to El Nino, which in its positive phase is associated with more warming, the NOAA climatolog­ist said.

Even with a scorching July and a nasty June, this year so far is only the sixth warmest on record. That’s mostly because 2021 started cooler than recent years due to a La Nina cooling of the central Pacific that often reduces the global temperatur­e average, Sanchez-Lugo said.

“One month by itself does not say much, but that this was a La Nina year and we still had the warmest temperatur­es on record … fits with the pattern of what we have been seeing for most of the last decade now,” said University of Illinois meteorolog­y professor Donald Wuebbles.

While the world set a record in July, the United States only tied for its 13th hottest July on record. Even though California, Nevada, Oregon and Washington had their hottest Julys, slightly cooler than normal months in Texas, Oklahoma, Kansas, Arkansas, Missouri, Alabama, Maine, Vermont and New Hampshire kept the nation from approachin­g record heat levels.

Newspapers in English

Newspapers from United States