University of Southampton: Earth's atmosphere is 'thirstier'

The study shows that rising atmospheric demand for water is making droughts around the world up to 40 per cent more severe.

While droughts are often blamed on low rainfall, scientists found that the atmosphere itself is pulling moisture from soil, rivers, and plants at an accelerating rate—a process known as atmospheric evaporative demand (AED).

Professor Justin Sheffield, co-author of the study and professor of hydrology and remote sensing at the University of Southampton, said: "It soaks up moisture faster than it can be replaced, which can increase water stress, particularly for plants.

"As the world gets hotter from climate change, AED is rising, which is causing more severe droughts even in wet regions."

The research, published in *Nature*, was a global collaboration between researchers at Southampton and other universities.

Although AED was already known to play a role in drought, this study is the first to measure its global impact using more than 100 years of real-world data.

The findings reveal that even wetter regions are experiencing more severe droughts—not just because of reduced rainfall, but because the atmosphere is demanding more water from the land.

In the past five years, the extent of land under more intense drought conditions has risen by 74 per cent, mostly due to the atmosphere’s growing "thirst."

Professor Sheffield said: "It shows that it is not just rainfall that matters—how much water the atmosphere demands is just as important.

"As the planet warms, AED will likely keep rising, drying out landscapes faster than rain can keep up, increasing plant water stress, and impacting plant carbon uptake.

"We will need to study how farmers, cities, and ecosystems can adapt to a world where the atmosphere constantly demands more moisture."

The University of Southampton is ranked among the top 100 universities globally in the QS World University Rankings 2025 and is known for its research and international collaborations.