A pair of heat waves in France have been linked to the deaths of 1,435 people this summer by the country's health ministry.

Two bouts of record-setting heat hit France and other parts of Europe from June 24 to July 7, and July 21 to July 27. The French Health Ministry said in a news release that the death rate during the two heat waves was 9.1 percent higher than usual.

France and much of Europe saw record-breaking temperatures this summer. France recorded its highest-ever recorded temperature – 45.9 degrees Celsius – on June 28 in the southern town of Gallargues-le-Montueux, according to the French national weather service.

Experts worry heat waves such like these, driven by rising temperatures caused by greenhouse gas emissions, could become the new normal for Europe.

Much of the continent isn’t built to cope with extreme heat. Fewer than 5 percent of all European households are air-conditioned, according to a 2017 report, and public transport can grind to a halt in intense heat.

Elderly populations are particularly vulnerable. The French Health Ministry said 974 of the people whose deaths were linked to the summer heat were older than 75. Ten people died while working, the ministry said – eight during the first wave and two in the second. The majority had been working outdoors.

France has seen deadly heat waves before. Similar episodes during the summers of 2015 and 2018 saw the death rates rise by 10.1 percent and 15 percent, respectively, the ministry said.