Giant 'heat storms' are scorching the Earth

By Maurice Tamman, Ben Welsh, Pete Mckenzie, Charlie Szymanski, Delgerzaya Delgerjargal, Robbie Corey-Boulet, Loucoumane Coulibaly, Jeff Horwitz and Joan FausIn less than a lifetime, about six and a half decades, heat waves have evolved from sporadic, isolated episodes to massive, cascading weather events that can blanket vast swaths of the planet for months or even years at a time.The largest heat wave of the 1960s reached about 6% of the planet as it drifted for 46 days over the Atlantic Ocean, parts of Latin America and West Africa.The largest one this decade swept across almost 85% of the globe during its 367-day lifetime, stretching into the polar latitudes and touching virtually every human being on Earth.To continue calling such sprawling phenomena "heat waves" would be like calling a monsoon a rain shower. To understand the new reality of these immense expanses of heat, Reuters consulted with two dozen meteorologists and climate researchers - and analyzed temperatures for every hour of every day since 1960 for more than one million grid squares covering the entire globe. Out of those results we developed a new concept: the "heat storm."Simply put, heat storms are supersized heat waves. Reuters uses a conservative benchmark to define an ordinary heat wave: five or more consecutive days of abnormally high temperatures. Then we define the largest heat waves - those that at their peak cover at least 1% of the globe, roughly half the size of Canada - as heat storms.Applying this definition, Reuters identified a startling transformation. Heat storms were rare in the 1960s, when they averaged about five active storms per year. This decade, heat storms have swarmed the planet, averaging about 102 a year.One of them caused this summer's deadly heat in Europe, notching the highest June temperatures ever recorded in Bordeaux, Budapest, and Bilbao, the latter of which hit 42.7 degrees Celsius (108.9 degrees Fahrenheit). Roasting Europe for most of June and July, the heat storm warped steel railroad tracks, drove what European governments estimated were more than 10,000 excess deaths in a single week, and prompted Belgian zookeepers to cool their tigers by feeding them raw meat encased in ice.The largest heat storm on record - the one that lasted for 367 days over 2023-2024 and reached almost 85% of the globe - sent temperatures in parts of the Philippines up to 38 C (100.5 F), immiserating students in the country's mostly unairconditioned schools. In Manila, math teacher Joel Arrojado recalled a student who was face-down at his desk, crying. When Arrojado coaxed the boy into looking up, Arrojado saw his face and chest covered in blood. The boy, Arrojado said, had suffered a spontaneous nosebleed, a common problem in extreme heat. As more blood pumped from his nostrils, Arrojado recalled, the child pleaded with Arrojado to call his mother.As the same heat storm encased southern Louisiana for months, it exacerbated a historic drought.The state burned, suffering what the governor called "theworst wildfire we've seen since at least the Second World War" - and close to 600 other fires in August alone. Two months later, smoke from a smoldering marsh fire developed into a blinding "super fog" that caused a highway pile-up of at least 158 cars, killing seven people.The same heat storm helped fuel a 2023 Mediterranean cyclone that dropped massive rains over Libya. In the dead of night, two dams burst near the coastal town of Derna, washing away entire neighborhoods. A week later, on her hands and knees, Sabreen Blil clawed with her bare hands at the rubble of her brother's house, hoping to dig out the dead. As she wept, she recited their names. "Taym, Yazan, Luqman, Salmah, Tumador, Hakim and his wife. Oh my God. My family, where are you?" she wailed. "Oh God. Even just one - my God - just let me find even one body."During the annual Hajj pilgrimage in Saudi Arabia, the heat storm drove temperatures at Mecca's Grand Mosque to 51.8 C (125.2 F), killing more than 1,300 pilgrims. Bodies lay in the streets. And as Europe's largest recorded fire spread in Greece during the span of that same heat storm, the inferno killed migrants traversing the thick Dadia forest. Their corpses remained in the woods for days; even the vultures that might have fed on the bodies had fled the flames.These far-flung and seemingly unrelated catastrophes all shared a common connection: one single heat storm.Heat storms inflict "a major disruption to global civilization," said James Renwick, professor of physical geography at New Zealand's Victoria University of Wellington. "Heat is the biggest killer from climate change," he said, noting that it can lead to "famine, hunger, death, conflict over resources."A NEW WAY TO UNDERSTAND CLIMATE CHANGEHeat storms constitute a new way to conceptualize how Earth's climate is changing as humanity pumps greenhouse gases into the atmosphere.The determination by climatologists that the average global…