New Study Finds European Heatwave Caused by Climate Change

A rapid study released on Friday (26/06) by World Weather Attribution (WWA) found that this year’s heatwave was nearly impossible five decades ago. In fact, the likelihood of it occurring is now 200 times greater than it was 20 years ago. Millions of people in France, Italy, Spain, the United Kingdom, and various other parts of Europe experienced extreme temperatures and humidity this week due to a heat dome phenomenon. Daytime temperatures in many places exceeded 40 degrees Celsius (104 degrees Fahrenheit), while persistently high night-time temperatures made it difficult for bodies to cool down and recover from heat exposure. Scientists estimate that if a heatwave with similar characteristics had occurred under the climate conditions of June 1976, daytime temperatures would have been about 3.5 degrees Celsius (6.3 Fahrenheit) lower. If it had occurred in the climate of 2003, daytime temperatures would have been about 2 degrees Celsius (3.6 Fahrenheit) lower. Meanwhile, night-time temperatures are estimated to have been about 2.4 degrees Celsius (4.3 Fahrenheit) lower in June 1976, and about 1.3 degrees Celsius (2.3 Fahrenheit) lower in 2003. The years 1976 and 2003 were chosen as comparisons because extreme heatwaves occurred in Europe in both those years. “The increase in temperature this time is so drastic that we estimate such an event would not have been possible under the climate conditions of 1976,” said the study’s lead author, Theodore Keeping, a climate scientist from the Centre for Environmental Policy at Imperial College London. “Even compared to the climate conditions 23 years ago, in 2003, an event like this would still have been very, very rare.” World Weather Attribution (WWA), a collaboration of scientists based in Europe that researches the causes of various extreme weather events worldwide, has since 2015 analysed the extent to which such events can be linked to climate change caused by the burning of fossil fuels like coal, oil, and gas. This latest research used observed temperature data and weather forecasts to analyse the heatwave that began on 18 June. The study also found that 45 per cent of the 850 cities analysed across 30 European countries have broken or are expected to reach record levels of heat stress, a measure that accounts for the combination of temperature and humidity. “This indicator is directly related to the heat stress experienced by the human body and the body’s ability to cool itself. It is a very good measure for estimating the health impacts that this heatwave can cause,” Keeping said. The combination of heat and humidity is indeed very dangerous for humans. WWA researchers stated that this event is the most severe heatwave ever recorded in that European region, as well as the most extreme humid heat event ever to occur there. Europe is the fastest-warming continent in the world. According to the European Union’s Copernicus Climate Change Service, temperatures in Europe have been rising twice as fast as the global average since the 1980s. In a separate study last year, WWA researchers estimated that around 1,500 deaths during last summer’s heatwave in Europe were caused by climate change. This week, meteorological agencies in various European countries issued red alerts for extreme heat. As a result, various sports activities, schools, public transport, and tourist sites were restricted. Many European countries also lack widespread use of air conditioning and other adequate infrastructure to cope with the increasingly hot climate. France, one of the countries most affected by this heatwave, recorded its hottest day in history this week. The country also reported 40 deaths from drowning, as many people sought places to cool off. WWA scientists confirmed that the ongoing El Niño warming cycle played no role in causing this heatwave. Europe also experienced record-breaking temperatures in May, even though much hotter weather typically occurs in July and August. Michael Mann, a climate scientist from the University of Pennsylvania who was not involved in the study, said the findings were plausible but likely underestimated the role of climate change in the heatwave. “If anything, this latest assessment—and similar studies—tend to underestimate the extent to which climate change is playing a role in these events,” Mann said. Keeping said the European heatwave demonstrates the importance of adapting infrastructure and human behaviour to extreme temperatures. “We must prepare for events like this. In the near future, they will only become more frequent,” Keeping said. “We must also address the root cause of climate change, which is carbon emissions from burning fossil fuels.”