Extreme summer droughts in Europe could double in frequency due to climate crisis

(CN) — Regions of Europe could see double the amount of extreme summer droughts under the current trajectory of climate change, according to a new study published Tuesday.

The research article was published in the journal Frontiers in Water and authored by scientists at the Ludwig Maximilian University of Munich in Germany and Ouranos Consortium. They used a scenario where greenhouse gas concentrations continue on their current trajectory to model the drought conditions from 2080 to 2099 if no policies are implemented or changed to curb greenhouse gas emissions. They compared the long-term future to recorded conditions from 2001 to 2020.

The results showed that four regions of Europe could be poised to experience extreme summer droughts that are increasingly frequent and intense. France, the Alps, the Mediterranean and the Iberian Peninsula are the regions where the researchers expect droughts to hit the hardest.

“We find a clear trend towards more, longer and more intense summer droughts, in terms of a precipitation deficit, towards the end of the century under a high-emission carbon scenario,” said study author Magdalena Mittermeier in a statement accompanying the study’s release.

The research suggests summers will become more intensely dry while wintertime drought could decrease in frequency and become less severe in some areas. Experts attributed this to the warming of the climate.

“One of the things that cause that type of decrease [in wintertime drought] is the ability to hold more water vapor and rain out heavier when it does rain. The opposite is true in the summer,” said Norman Miller, an adjunct professor emeritus studying climate change impacts at the University of California, Berkeley. “As the atmosphere warms, it holds more water vapor. The result is a really simple statement: dry regions get dryer; wet regions get wetter. What we’re seeing now around the planet are a combination of impacts as a result of the ability to hold water vapor as the planet warms.”

Isla Simpson, a research scientist in climate and global dynamics at the National Center for Atmospheric Research, concurred with Miller’s assessment.

“The atmosphere is going to be warmer, so it can hold more moisture, which means it has more thirst for the moisture that is in the ground and will lead to drying of soils,” Simpson said.

The study indicates that meteorological droughts – those characterized by dryness and limited precipitation — can be a harbinger of droughts affecting agriculture, socioeconomics and the water levels in bodies of water.

“A lot of people associate drought with a lack of precipitation. But as the planet continues to get warmer, the real impact is the drying down of the soil,” said Miller. “As a result of that increasing evaporation, which is due to increasing temperature, hydrologic and agricultural drought intensifies dramatically.”

Simpson said the latest research was helpful, but that there were still more scenarios and models to be tested to help scientists reach a consensus about the effects of climate change on amounts of precipitation.

“We need to narrow down the uncertainties in our precipitation projection,” she said. “This quantification seems useful and I think we should endeavor to do that with other aspects of drought, [like] soil moisture. There’s many models out there, and they don’t necessarily all agree, but if we can narrow down that uncertainty, then we can hopefully get closer to the truth of what will actually happen.”

Amir AghaKouchak, a professor researching hydrology and climate extremes at the University of California, Irvine, said in an interview that the research from Mittermeier and her colleagues was analogous to some of his own research on the impact of anthropogenic emissions, or human-caused emissions, on droughts.

“Our previous research and this paper show a significant contribution of anthropogenic emissions. This is not limited to Europe,” AghaKouchak said. “In most places around the world, we will see some contribution from anthropogenic emissions on either drought frequency or severity or both.”

AghaKouchak said going forward, researchers will have to focus on examining the effects of the increasingly severe droughts on ecosystems and communities.

“We have made a lot of progress on isolating human impact. I don’t think the question of whether we have had an impact on droughts is relevant anymore — we know that,” said AghaKouchak. “Now the question is what are the long-term impacts beyond a generation or two.”

Miller agreed and said efforts among policymakers and everyday people should turn to mitigation and adaptation.

“Society needs to learn how to adapt to a decrease in water availability. We need to be more cognizant of how as a society use water as our most important natural resource,” Miller said. “Mitigation means trying to reduce emissions that wind up [forcing] us to adapt.”