Extreme 'Heat Dome' Impacting Olympics Impossible Without Global Warming
Scorching temperatures in Mediterranean and North African countries are already leading to an increase in premature deaths. The "heat dome" causing extreme temperatures across Western Europe and North Africa, affecting athletes and spectators at the Olympic Games in Paris, would not have been possible without human-induced global warming, according to a rapid analysis.
Scientists have determined that the climate crisis driven by fossil fuels has increased temperatures by 2.5C to 3.3C. Such an event would have been inconceivable in a pre-global warming world but is now expected to occur roughly once a decade. Continued emissions of heat-trapping carbon dioxide will only make these events more frequent, researchers warn.
"Climate change disrupted the Olympics on Tuesday," said Dr. Friederike Otto, a climatologist at Imperial College London and part of the World Weather Attribution group behind the analysis. "The world watched athletes struggle in 35C heat. If the atmosphere hadn't been overloaded with emissions from burning fossil fuels, Paris would have been about 3C cooler and much safer for sport."
Numerous athletes, including gymnastics star Simone Biles, have suffered in the heat, with one tennis player calling it "crazy" and sailing competitors wearing ice vests to stay cool. Fans watching beach volleyball near the Eiffel Tower were sprayed with hoses, misting fountains were set up at skateboarding and other venues, and millions of bottles of water were distributed at train and Metro stations.
"However, many people across the Mediterranean do not have the luxury of ice packs, air conditioning, or cooling breaks at work," Otto added. "For these people, extreme heat can mean death."
The analysis assessed the dangerous heat in July that sent temperatures soaring past 40C in many areas, increasing wildfires in Portugal and Greece and worsening water shortages in Italy and Spain. In Morocco, temperatures reached 48C, with one hospital reporting 21 deaths.
The heat will have caused many more people to die prematurely across the region. However, collecting the necessary data takes time. Extreme heat during the European summer of 2022 is now known to have caused 61,000 early deaths.
Dr. Mariam Zachariah, a research associate at Imperial College London, said: "[Our new] analysis helps people understand that climate change is not a distant threat, but an immediate one that is already making life on Earth much more dangerous."
Heat action plans, which include early warning systems, water and first aid stations, and adjusted hours for outdoor workers, have been implemented in France, Greece, Italy, Spain, and Portugal, but not yet in Morocco.
The July heatwave was caused by a large-scale high-pressure ridge, often referred to as a "heat dome." It followed 13 months of extreme global heat, with each of the last 13 months being the hottest ever recorded.
The climate crisis is making all heatwaves hotter, longer, and more frequent worldwide. Scientists assessed the impact of human-caused global warming on the extreme July heat by comparing how these events have changed between today's climate, with about 1.3C of global warming, and the cooler preindustrial climate.
The analysis built on studies of heatwaves in the Mediterranean region in April and July 2023, using weather data and computer climate models. This foundation allowed the new analysis to be produced almost immediately using only weather data.
Many hundreds of these attribution studies have now been completed, covering heatwaves, wildfires, droughts, floods, and storms. They include a growing number of events that would otherwise be impossible and demonstrate how human-caused warming has already intensified extreme weather globally.
"As long as humans burn oil, gas, and coal, heatwaves will get hotter, and more people will die premature deaths," said Otto. "The good news is that we don't need a magic solution to stop things from getting worse. We know exactly what we need to do and have the technology and knowledge required to do it – replace fossil fuels with renewable energy and stop deforestation. The faster we do this, the better."
UN Secretary-General António Guterres said last week: "I must call out the flood of fossil fuel expansion we are seeing in some of the world's wealthiest countries." He spoke a day after the Guardian revealed a surge in fresh oil and gas exploration in 2024, with countries such as the US and the UK leading the charge, issuing a record 825 oil and gas licenses in 2023.