Data published by two leading climate monitors this Monday says that Europe endured a record number of 'extreme heat stress' days in 2023, underscoring the threat of increasingly deadly summers across the continent.
In a year of contrasting extremes, Europe witnessed scorching heatwaves but also catastrophic flooding, withering droughts, violent storms and its largest wildfire.
According to the EU's Copernicus Climate Change Service and the UN's World Meteorological Organization in a new joint report published this Monday, these disasters inflicted billions of dollars in damages and impacted more than two million people.
The consequences for health were particularly acute, with heat singled out by these agencies as the biggest climate-related threat as global warming drives ever-hotter European summers.
European State of the Climate 2020 report by @CopernicusECMWF 🌍
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2020 was the warmest year on record for Europe.
🌡️Exceptional Arctic heat, with temps 6°C above average
🌡️Warmer winter & autumn than any other year
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Thermal Climate Index
"We're seeing an increasing trend in the number of days with heat stress across Europe and 2023 was no exception, with Europe seeing a record number of days with extreme heat stress," said Rebecca Emerton, a climate scientist at Copernicus.
For this study, Copernicus and WMO used the Universal Thermal Climate Index, which measures the effect of the environment on the human body.
It takes into account not just high temperatures but also humidity, wind speed, sunshine, and heat emitted by the surroundings.
The index has 10 different categories of heat and cold stress, with units of degrees Celsius representing a 'feels-like' temperature.
Extreme heat stress "is equivalent to a 'feels-like' temperature of more than 46 degrees Celsius, at which point it's imperative to take actions to avoid health risks such as heat stroke", Emerton said.
'Extended summer'
Prolonged exposure to heat stress is particularly dangerous for vulnerable people such as the elderly or those with pre-existing health conditions, with the effects extreme heat much stronger in cities.
Twenty-three of the 30 worst heatwaves on record in Europe have occurred this century and heat-related deaths have soared around 30 percent in the past 20 years, the report said.
2023 was not the hottest summer in Europe – it was, in fact the fifth hottest – but that doesn't mean it wasn't blazing.
Much of Europe sweltered from heatwaves during an "extended summer" between June and September, Emerton said.
September was the warmest on record for Europe as a whole, she added.
Serious consequences
Scientists agree that greenhouse gas emissions are warming the planet, causing more intense and frequent extreme weather events.
Europe is warming twice as fast as the global average and heatwaves will become longer and more powerful in future, the report said.
This – coupled with ageing populations and more people moving to cities – will have "serious consequences for public health", it added.
2023 was the hottest year globally on record and oceans, which absorb 90 percent of excess heat produced by carbon dioxide emissions, also warmed to new highs.
Glaciers in all parts of Europe saw a loss of ice, while Greece suffered the largest wildfire in the history of the EU.
2023 was also one of Europe's wettest years, with major flooding affecting 1.6 million people, and storms a further 550,000.
Emerton said that economic cost of these extreme events was over €13 billion – about 80 percent attributed to flooding.
