Heat, Not Rainfall, Is Now the Primary Driver of Europe's Droughts, Landmark 2026 Study Finds

Crucially, the study found that even in regions where annual rainfall remains the same or increases, warmer temperatures dry out soil faster than rain can compensate, leading to more frequent and severe agricultural droughts . This is consistent with the IPCC's Sixth Assessment Report, which has high confidence that increases in evapotranspiration driven by increased temperature are contributing to agricultural and ecological droughts in some regions .

Europe's Hottest June on Record Sets the Stage

The June 2026 heatwave provided the extreme conditions that the WWA study examined. The Copernicus Climate Change Service confirmed that June 2026 was the hottest June ever recorded in western Europe, with average temperatures reaching 20.74°C, which is 3.05°C above the 1991-2020 average . Globally, it was the second-warmest June on record .

Europe is widely documented as the fastest-warming continent, heating at roughly twice the global average rate . The WWA scientists emphasized that this long-term warming trend is making severe heatwaves and the resulting heat-driven droughts more frequent and intense.

Devastating Agricultural Impacts: The Numbers Tell the Story

The agricultural consequences of this shift are stark, particularly for Europe's maize (corn) and other grain crops, which are highly sensitive to water stress during their flowering and grain-filling stages.

France: Smallest Maize Harvest in 50 Years

France, the European Union's largest grain producer, was hit especially hard. The USDA forecasts French corn production for the 2026/27 marketing year at 10.0 million metric tons (mmt), which represents a 26% decline year-on-year and is the lowest production since 1990/91 . Some analysts project output could fall even further, potentially below 8 million tonnes—the lowest since 1976 .

The WWA study cited preliminary estimates from the French Agriculture Ministry indicating that the June heatwave alone may have destroyed up to 30% of French corn output . The extreme weather also scorched about half of the country's carrot production and 60% of its hops, and killed hundreds of thousands of poultry .

The damage extends to wheat. France is now forecast to produce 32 million tonnes of wheat in 2026, a decline largely driven by deteriorating growing conditions and successive heatwaves, according to the French agriculture ministry's Agreste service .

Romania: Over a Million Hectares Lost

Eastern Europe also suffered catastrophic losses. In Romania, farmers lost over one million hectares of crops due to persistent drought conditions that carried over from 2025 . The country's drought was so severe that the government restricted farmer access to water for irrigation . The WWA analysis found that the likelihood of such agricultural droughts in eastern Europe has increased elevenfold due to climate change .

Continent-Wide Losses

The broader European picture is grim. An analysis by the European association Coceral, cited in the WWA study, estimated that the June heatwave cost European grain farmers €2 billion in lost revenue and destroyed about 10 million tonnes of crops across the continent . The EU's maize harvest forecast was cut by nearly 8% to 52.7 million tonnes, the lowest since 2007 . The total expected grain loss across Europe is approximately 9 million tonnes .

Beyond Farms: River Disruption and Wildfires

The impacts of this heat-driven drought extended beyond agriculture. Low water levels in rivers across Romania, Greece, and other countries disrupted shipping, farming operations, and industrial processes . Meanwhile, the combination of extreme heat and bone-dry vegetation fueled deadly wildfires that raged through Spain and France . The European Drought Observatory confirmed that alert conditions had emerged across a wide swath of Europe, including France, Germany, Austria, Hungary, and the UK .

Projected Worsening at 2.8°C Warming

The WWA study also looked to the future, issuing a stark warning about the path the world is on. Under current policy trajectories, global warming is projected to reach 2.8°C above pre-industrial levels. The scientists concluded that at this level of warming, extreme heat-driven droughts will become even more frequent, more severe, and more widespread .

Scientists' Warnings: Emissions Cuts Are the Only Solution

Across the reporting on the study's release, scientists were unequivocal in their message. The root cause of the crisis, they emphasized, is not simply a shortage of rain—it is heat, and that heat is caused by the burning of fossil fuels .

"Climate change is rewriting Europe's water balance from the demand side, not just the supply side," climatologist Jozef Pecho summarized in a post about the study . The researchers stressed that swift and deep cuts to carbon emissions are the only way to prevent the situation from worsening dramatically .