Europe swelters in historic heatwave

Record-breaking temperatures for the time of year are likely to occur across a large part of western Europe in the coming days as a historically unprecedented heatwave intensifies.

Temperatures will widely exceed 40°C across Spain and parts of France, with the UK June temperature record potentially being beaten as well. Large parts of Europe will be 14-15°C above the long-term average as the heatwave peaks on June 30 and July 1.

“Maximum mean summer temperatures for West Central Europe are now higher than France was from 1961-1990,” says climatologist Lee Simons. “The rate of European warming is higher than any other continent.”

Countries across southern Europe – particularly Italy, Greece, Spain and Turkey – are reporting daytime temperatures consistently exceeding 40°C, with some regions pushing toward 45°C, especially inland. North Africa and parts of the eastern Mediterranean, including Cyprus and southern Turkey, are also being severely affected. Night-time temperatures are unusually high as well, providing little relief and increasing the risk of heat stress.

The European meteorological services have issued an amber warming, but some EU countries have already issued red alerts, urging people to avoid outdoor activity during peak hours, stay hydrated and check on vulnerable individuals. Hospitals in Rome, Athens and Madrid have reported a spike in heat-related emergencies, including dehydration, heatstroke and complications among the elderly and those with chronic conditions.

The World Meteorological Organization (WMO) has warned that such heatwaves are becoming more frequent, intense and prolonged due to climate change. Meteorologists say this current event is being driven by a high-pressure system trapping hot air over the region, compounded by dry ground conditions.

In addition, agricultural output may suffer, particularly for heat-sensitive crops such as olives, grapes and vegetables. Video posted on social media shows that crops in Hungary have already died, while crop yields in countries such as France are expected to fall this year. Water reserves are also under strain, with several regions having reintroduced restrictions on non-essential water use.

Forecasts suggest the heatwave could persist into early July, particularly in southern and eastern Europe. Temperatures may moderate slightly in northern Europe, but the Mediterranean basin will remain subject to exceptionally hot conditions.

Spanish city hits all-time high of 46C

Spain is bearing the brunt of the heatwave as a high pressure system funnels hot air from Africa over southern Spain. New all-time high temperate of 46°C was recorded in El Granado on June 28, beating the previous record of 45.2 °C set in Seville in June 1965.

Mediterranean bath water shutting down French nuclear power plants

Parts of the Mediterranean are now running more than 5-6°C above their long-term average as well, or around eight standard deviations from the average. In statistics anything more than two standard deviations from the average is usually considered an extreme departure from normal.

The water temperature in the Mediterranean is now so high that scientists warn France may have to shut down its nuclear power stations as the water is not cold enough to cool the reactors. Temperatures in Mediterranean already exceed 25C from mid-June, the European Union's Copernicus program reports. 

France’s utility company EDF has already issued several warnings. The most recent affected site was the Blayais nuclear power plant near Bordeaux on the Atlantic, where four reactors with a total capacity of 3,600 megawatts are operated. Due to the expected high temperatures in the Gironde River, which flows into the Bay of Biscay, power reductions may occur starting June 30, according to EDF as the available water is not able to adequately cool the reactors.

EDF had previously also issued warnings for the Bugey and Golfech nuclear power plant sites. The Bugey nuclear power plant, with four reactors and an output of around 3,600 megawatts, is located on the Rhône River, which flows into the Mediterranean Sea. The Golfech site, with two reactor units, each with a gross output of 1,360 megawatts and a total output of 2,700 megawatts, is located in the municipality of the same name in southwest France, directly on the Garonne River between Toulouse and Agen. The Garonne flows into the Gironde, which flows into the Atlantic Ocean and the Bay of Biscay.

CO₂ emissions at all-time high

Atmospheric CO₂ emissions are currently at an all-time high and the highest it’s been in the last 14mn years at 426 parts per million, say scientists. The last time CO₂ concentrations were this high was in the Middle Miocene epoch. Then temperatures were 3-6°C warmer globally, sea levels were higher by as much as 40 meters, and there was no permanent arctic sea ice.