World likely has hottest summer on record
The first of many batches of temperature data is in for August — and not only did the globe have its hottest such month on record, but temperature anomalies secured meteorological summer's place in the history books.
- According to preliminary data from the Copernicus Climate Change Service's ERA5 data set, the global average surface temperature for June through August was about 0.65°C (1.17°F) above the 1991-2020 average.
- This beat the previous record warm summer of 2019 by nearly 0.3°C (0.54°F).
- August alone had a global average surface temperature of 0.71°C (1.29°F) above the 1991-2020 average, crushing August 2019, which was only about 0.37°C (0.66°F) above the long-term average.
- June and July were each record warm months, with July ranking as the warmest month ever recorded since the dawn of the instrument era in the 19th Century.
Zoom in: Numerous U.S. cities in the southern tier set records for their hottest June-through-August periods.
- This includes: New Orleans, Miami, Baton Rouge, Houston, Corpus Christi and Phoenix. Many others had a top-10-warmest meteorological summer on record, including Dallas, Atlanta, Austin, Jacksonville, Albuquerque and Santa Fe.
- Cities in the Pacific Northwest also had a top-10-warmest summer, including Portland and Seattle.
- Globally, Australia had its warmest winter on record since reliable records began there in 1910, and all-time winter heat records were set in multiple locations in South America, from Brazil to Chile on northward.
- Europe saw repeated, scorching heat waves that broke all-time seasonal records in Spain, France, Italy, Greece, Switzerland and other nations. The E.U.'s largest wildfire on record has continued to burn in Greece, though in a case of weather whiplash, flash flooding is more of a concern there during the next few days.
Of note: In Tokyo, a city of about 14 million, daytime highs rose above 86°F every day during August, which was a first for any month since data began there in 1875, according to meteorologist Sayaka Mori.
- In Japan, August was the country's hottest month of any month on record. The nation also saw its hottest summer, according to the Japan Meteorological Agency.
Between the lines: These examples from land miss some of the most important and far-reaching effects of climate change during the past few months and longer: record-warm oceans.
- Across the globe, ocean temperatures are at record highs, and the heat going into the oceans has significant consequences for those on land, since it adds more moisture and heat to storm systems.
- For example, record warmth in the Gulf of Mexico elevated air temperatures from Miami to Houston, and also provided the fuel needed for Hurricane Idalia, which struck Florida last week, to rapidly intensify when nearing landfall.
- Record water temperatures are already fueling an unusually active El Niño hurricane season in the tropical North Atlantic Ocean. Corals are bleaching and dying from the Florida Keys to the Caribbean.
The intrigue: There is no great mystery surrounding what is helping to drive these heat records, on land and sea, with the burning of fossil fuels for energy along with deforestation and agricultural practices are increasing the amounts of heat-trapping greenhouse gases in the air.
- A periodic El Niño event in the tropical Pacific Ocean is also adding additional heat to the global climate system.
- This has been a summer featuring a fusillade of extreme events, however, which has the potential to yield changes in national and possibly international climate policies.
Yes, but: Climate scientists are not seeing unanticipated climate events play out, since most of what is happening is contained in the volumes of studies on the topic.
- But some of the recent impacts are happening sooner than previously expected, and having greater societal consequences than initially thought.
What's next: During the next two weeks, official data will emerge from global climate monitoring centers. These are unlikely to change the major themes of the climate change story of 2023: a record-warm year that is increasingly likely to break all-time annual milestones, to be followed by an even hotter year in 2024.