‘Scorching, dry summers’: Heat rather than lack of rain is now to blame for Europe’s droughts

“This isn’t just a crisis for farmers, it’s a crisis that trickles down to Europe’s most vulnerable,” says researcher Merel Laauwen. Scientists say Europe’s droughts are increasingly being driven by scorching heat rather than a lack of rain, with soil moisture disappearing “faster than it would in a world without climate change”. France is heading for its worst maize harvest in 50 years. Romania has lost more than a million hectares of crops. Rivers across the continent are running so low that shipping lanes are disrupted and energy production is under strain. According to a new study, the root cause isn’t simply a shortage of rain – it’s heat. Research by World Weather Attribution (WWA), an international collaboration of climate scientists, has found that record-breaking summer heat is supercharging drought across Europe by evaporating water out of the soil faster than it can be replenished. Scientists from 12 European countries analysed rainfall trends, agricultural drought (soil moisture) and “potential evapotranspiration” – a measure of the atmosphere’s ‘thirst’ or its ability to evaporate moisture – to work out how much of a role climate change is playing in this year’s drought. They concluded that, while long-term rainfall trends across the continent vary, it’s extreme heat that is turning ordinary dry spells into severe droughts. Soil moisture is disappearing at an alarming rate The study found that agricultural soil droughts in Western Europe are now five times more likely because of climate change. In Eastern Europe, where dry conditions have already dragged on for six months, soil droughts are 11 times more likely. In Western Europe, climate change was not found to be the primary driver of the lack of rain itself – but it is making once-rare heatwave conditions far more common, dramatically shifting how thirsty the atmosphere has become. The same amount of low rainfall that might once have caused a mild, manageable dry spell is now tipping into serious drought – because the additional heat is pulling moisture out of the ground far faster than before. In Western Europe, heatwaves capable of driving these intense evaporative conditions are now around 80 times more likely to occur than in a world without climate change. In Eastern Europe, they are around 40 times more likely. ‘Extreme heat is taking over as the primary driver of drought’ in Europe “Europe’s climate is shifting fast,” says Dr Sarah Kew, a climate scientist at the Royal Netherlands Meteorological Institute (KNMI). “While rain patterns remain mixed, our findings show that extreme heat is taking over as the primary driver of drought on our continent. “We are seeing water supplies evaporate out of our soils and rivers faster than we would have in a world without climate change, turning what would have been manageable dry spells into severe droughts.” Dr Dominik Schumacher, from the Institute for Atmospheric and Climate Science at ETH Zurich, says the pattern marks a shift in how European droughts form in the first place. “Despite more wintertime rainfall across most of Europe, we now see an enhanced tendency for unusual soil drying already in spring, before summer has even begun,” he says. “That is our own doing: as temperatures climb, the atmosphere’s thirst increases quickly, sucking moisture out of rivers, lakes, reservoirs and the soil. “This fundamentally changes how European droughts form – less and less through missing rain, and more and more through warmer air that prevents the rain from staying in the ground.” Food prices and vulnerable households are on the front line The consequences are already being felt far outside of farmers’ fields. Crop failures, low rivers and strained energy systems are threatening to push up the price of essential household items – a burden that falls hardest on low-income households. “This isn’t just a crisis for farmers, it’s a crisis that trickles down to Europe’s most vulnerable,” says Merel Laauwen of Wageningen University & Research in the Netherlands. “Crop losses, low river levels, and water use restrictions threaten to drive up the price of basics like food and energy, hitting low-income households hardest. “Although science is telling us that we will see more frequent and intense droughts in the future, drought management plans are still not mandated by the EU and we see inconsistent preparedness across European countries.” Drought conditions could become the new normal as temperatures rise With temperatures projected to keep rising if planet-heating emissions are not urgently reduced, drought conditions in Europe could rapidly worsen. “What’s most alarming is that these conditions are occurring at 1.4°C of warming,” says Dr Mariam Zachariah of the Centre for Environmental Policy at Imperial College London. “If global emissions push temperatures up to 2.8°C as predicted, these intense evaporative conditions could double in likelihood, turning droughts like this one into regular occurrences.” She warns that “scorching, dry summers” will become a yearly occurrence in Europe if swift action isn’t taken. Simon Stiell, executive secretary of UN Climate Change, calls Europe’s worsening droughts an “unignorable red alert that our planet is overheating as the climate crisis gets rapidly worse”. “Until humanity stops burning huge amounts of coal, oil and gas, these brutal climate-driven droughts will only get more severe and more costly for households and whole economies alike,” he warns. “But the solutions are just as clear: move much faster to renewable energy – which is now cheaper than polluting fossil fuels – electrify economies and invest in resilience so that communities, businesses and economies are better protected.”