With extreme heat now a public health crisis, local data can save lives

Share: X (Twitter) Facebook LinkedIn WhatsApp Email Print Eric Mackres is senior manager of urban analytics for the WRI Ross Center for Sustainable Cities and attended London Climate Action Week during the June 2026 heatwave. Usama Bilal is an associate professor of epidemiology and co-director of the Urban Health Collaborative at Drexel University. As thousands gathered in London for one of the year’s largest climate gatherings last week, Western Europe faced its most severe heatwave ever recorded. The irony was not lost. Across Europe, over a dozen countries issued urgent heat warnings and the World Health Organization recorded over 1,300 excess deaths. In London, where air conditioning is rare in buildings and on trains and buses, temperatures soared past 36 degrees Celsius (97F) and schools closed early. The mayor announced the city’s first heat action plan - an important step. Extreme heat is now a public health crisis for many of the world’s cities, as the urban heat island effect intensifies dangerous temperatures - and it’s growing worse. Around 500,000 people die from extreme heat every year. As global temperatures rise, and with a severe El Niño getting underway, even more people will die and be hospitalised unless cities act soon. But most cities are still taking a far too one-sized-fits-all approach to tackling heat, looking only at temperatures and not its local effects on people and their health. Log in here → Continue reading with free access For 15 years, Climate Home News has rigorously reported on the decisions shaping our climate. Join the community of readers who make this work possible. Join free and keep reading → It takes less than a minute. ×Log in to your account Forgot your password? Eric Mackres is senior manager of urban analytics for the WRI Ross Center for Sustainable Cities and attended London Climate Action Week during the June 2026 heatwave. Usama Bilal is an associate professor of epidemiology and co-director of the Urban Health Collaborative at Drexel University. As thousands gathered in London for one of the year’s largest climate gatherings last week, Western Europe faced its most severe heatwave ever recorded. The irony was not lost. Across Europe, over a dozen countries issued urgent heat warnings and the World Health Organization recorded over 1,300 excess deaths. In London, where air conditioning is rare in buildings and on trains and buses, temperatures soared past 36 degrees Celsius (97F) and schools closed early. The mayor announced the city’s first heat action plan - an important step.