The heat wave that hit the UK last week has become at least ten times more likely because of climate change, scientists said on Thursday.
On July 19, temperatures topped 40 degrees Celsius at Heathrow Airport and broke records at 46 local monitoring stations across the country. Emergency calls for ambulances soared and there were a series of grass fires on the outskirts of London.
Without human-caused climate change, which has warmed the world by 1.2°C above pre-industrial temperatures, such an event would have been extremely unlikely, scientists said.
“We are living in a world where temperatures are rising very fast,” said Friederike Otto, a climate scientist at Imperial College London. “With [aumentos de] 1.3º C or 1.4º C, this type of event will be much less rare.”
Climate change is making heat waves more frequent and more severe, according to the World Weather Attribution (WWA), an international collaboration of researchers that reveals the role of climate change in extreme events.
To determine how climate change influenced the odds of this particular heat wave in Britain, 21 WWA climate scientists, including Otto, performed a rapid analysis of the event using weather data and computer simulations to compare today’s weather with that of the past. past.
Before the industrial revolution and the rise in emissions that warm the planet, they found that the heat wave would have been much less likely to occur, and it would have been 4°C cooler.
However, the scientists added that their estimates are conservative, as extreme temperatures in Western Europe have increased more than in their climate model simulations.
“Climate models have a systematic bias as they underestimate the trend of extreme temperatures in summers in Western Europe due to climate change,” said Otto.
In May, the WWA stated that the heat wave in South Asia in March and April of this year had become 30 times more likely due to climate change, while last year’s heat wave in the Pacific Northwest would have been “virtually impossible.” ” without her.
Scientists have not been able to make such a definitive statement about Britain’s heat wave.
Still, climate scientists have expressed alarm at how quickly previous warnings are coming to fruition.
“Two years ago, UK Met Office scientists concluded that the probability of 40°C in the UK is now 1 in 100 in any year, up from 1 in 1,000 in the natural climate,” said Fraser Lott, a climate scientist at the Center. Hadley of the UK Met Office, in a statement. “It’s been worrying to see an event like this occur so soon after this study.”
