Something weird and worrying is happening with rain, study finds
Another one for the weird science dossier.
new research This shows that although the world is seeing more rain overall, the air is also becoming drier.
How can this happen? Simply put, the world’s precipitation is increasingly turning into larger storms, with longer periods of drought in between. And too much rain at once causes problems for the soil.
The findings are the first to show that a year’s worth of precipitation turning into larger, wetter storms means less water for groundwater resources and ecosystems, even as total precipitation increases, the study says. Since soil can only absorb a certain amount of water at a time, what is not absorbed collects on the surface and evaporates more easily.
Lead author of the study Corey Lesk“No matter how much precipitation falls, when rain and snow come in stronger bursts separated by longer periods of drought, there tends to be less water left on the land (in soils, lakes, and groundwater) for use by people and nature,” a Dartmouth College researcher who conducted the study while he was a lecturer at Dartmouth College explained it in an email to USA TODAY.
‘Making the soil drink water from the fire hose’
Researchers analyzed global precipitation records from 1980 to 2022 and determined that annual precipitation is becoming more intense regardless of whether the local climate is wet or dry, according to new research published May 13 in the peer-reviewed British journal Nature.
“We discovered that it’s not just the supply that matters, but also how it’s presented,” Justin Mankin, the study’s senior author and an associate professor of geography at Dartmouth, said in a statement. “Rain condensation is essentially asking the soil to drink water from a fire hose. When rainfall is heavy, you experience more consecutive dry days, but more importantly, heavier rains lead to surface ponding that is more easily evaporated by the atmosphere,” he added.
Climate news: Humans haven’t just made the planet warmer. We changed the way it rains.
“No matter where you are, more precipitation means less water is available to the land,” Mankin said. he said.
Is climate change to blame?
Researchers say this is a possible cause.
“We have not specifically tested the extent to which recent trends toward more intense precipitation are due to climate change,” Lesk told USA TODAY. “But these are consistent with what we would expect from theory about how warming shapes how precipitation is distributed over time.”
“We show that warming aggravates the drying membrane, regardless of whether total precipitation increases or decreases in the future,” he added.
Looking ahead, the study predicts that precipitation will increase further as global temperatures increase due to climate change. An increase of 3.6 degrees could lead to abnormally dry land conditions for 27% of the world’s population, which could offset any increase in total precipitation, the researchers note in the study.
“This is not a good effect that we’re uncovering,” says Lesk, now a professor of Earth and atmospheric sciences at the University of Quebec in Montreal. “It really lays out the mechanics of how climate change will impact water supplies for everyone.”
“The intensification of precipitation under global warming will lead to a drier land surface,” Mankin said. “What remains unresolved is whether future total precipitation changes can continue at the same pace.”
Cars and trucks are stranded and stalled on I-94 West near Trumbull in Detroit on June 26, 2021. Heavy rains in Metro Detroit caused major flooding of homes, streets and highways.
Challenge for water resource managers
An erratic boom-bust cycle of heavy rains and long droughts will make it difficult to manage public water supplies, especially in arid regions where water storage is critical, Mankin said in a statement.
“This adds a layer of difficulty to managing water resources — but the good news is that if we understand this concentration effect, we can better incorporate it into water management, drought forecasting, etc.,” Lesk told USA TODAY via email.
“Rain concentration is not often included in these assessments, largely because its importance has not been recognized until now,” he said.
Mankin said the study offers a new way of thinking about water resources by showing that how and when rain falls throughout the year is just as important as how much falls throughout the year. Climate scientists predict that a warmer climate will result in more rain, but whether that means more water for the soil is less certain, he added.
The walking bridge on the East River Trail is covered in water following heavy rainfall on April 14, 2026 in Ledgeview, Wis.
Western US warning
The United States west of the Mississippi River experienced some of the world’s highest levels of rain consolidation, with annual precipitation in the Rocky Mountains turning into 20% more intense downpours, according to the study.
California has faced this problem recently during long-term droughts when atmospheric rivers flooded the state, Mankin said. Water managers must decide whether to release precious water reserves to collect newly fallen rainwater, without being sure how long the new supply will last.
This article first appeared on USA TODAY: Rainfall patterns are behaving strangely and that’s a big problem, study says
