A new kind of drought

A new kind of drought is on the rise in Europe. ‘Flash’ droughts have emerged as distinct and concerning climatic extremes. They will occur more frequently and spread further as global warming continues.

Unlike conventional droughts, where a soil moisture deficit develops over months or even years, flash droughts develop in a span of a few weeks. Due to increased evaporative demand exacerbated by increased temperature and precipitation deficits, flash droughts are projected to be more frequent.

The future increase of the spatial extent and frequency of flash drought in Europe has been explored in a recent study. This was done step-by-step, from 1 °C to 3 °C of global warming, using five climate models. The analyses focused on the top 30 cm soil layer, corresponding to the near-surface root zone of plants.

Mainly northern and central Europe

According to the results of this study, the mean frequency of flash droughts across Europe will increase from around 3 events each decade today to around 5 events at 3 °C global warming. In the current climate, most of these droughts affect approximately 30% of the European land surface. This percentage is expected to increase to close to 44% at 3 °C global warming. So, each degree of additional global warming is expected to add around one more flash drought event each decade and more than 6% to the area across Europe under flash drought.

The increase of the spatial extent and frequency of flash droughts will be stronger in northern and central Europe than in the Mediterranean.

Soil moisture in northern and central European is generally higher than in southern Europe due to more frequent precipitation. Under these conditions, flash droughts can form rapidly when evaporation increases sharply at high temperatures and little precipitation. In the Mediterranean region, the soils are already dry and actual evapotranspiration is low. This region might observe more long-term conventional droughts instead of flash droughts.

Source: Yadav et al., 2025. Environmental Research Letters 20: 114046.