Global sea temperatures hit record high in July amid extreme heatwaves

July marked a new record for global sea surface temperatures, with scientists reporting the hottest July in recorded history. This surge occurred as Western Europe grappled with severe heatwaves, according to data from the EU's climate change monitoring service, Copernicus.

The Atlantic coast and the western Mediterranean saw sea surface temperatures reach unprecedented July highs. Intense marine heatwaves also affected waters surrounding Europe. Globally, the average sea surface temperature outside polar regions surpassed the previous July record set in 2023. The average air temperature for July 2024 was only marginally cooler than July 2023, leading scientists to consider both months the second hottest Julys on record.

In Western Europe, the June-July period was the hottest ever recorded, with Copernicus reporting that the first two summer months were 2.79°C above average. This sustained heat, described as "exceptional," fueled wildfires across large areas of the Mediterranean. Central Europe also experienced a heatwave, with several countries, including Austria and Slovakia, setting new national temperature records.

Samantha Burgess, a climate scientist at the European Centre for Medium-Range Weather Forecasts (ECMWF), stated that the summer serves as a "clear example" of how the climate crisis intensifies overlapping extreme events. She explained that high-pressure systems trapping heat in Western Europe coincided with extreme temperatures and widespread drought. As soil dries out, its natural cooling capacity diminishes, allowing heat to accumulate more easily.

Economists caution that the long-term damage from such events could far outweigh short-term losses, particularly if droughts persist for years. A working paper by the CMCC and the European Institute of Economics highlighted that a severe drought in Europe from 2015–2018 cost the economy 439 billion euros. While agriculture experienced significant but short-term impacts, manufacturing and construction faced smaller but longer-lasting consequences. Researchers suggest that conventional economic impact assessments often underestimate drought-related losses by not accounting for effects that linger for years.