Researchers suggest aerosol injections into the atmosphere and similar cloud seeding efforts could have unintended negative consequences. Photo by UPI/Shutterstock/Willyam Bradberry
Nov. 14 (UPI) -- Some scientists and policy officials have proposed artificial cooling as a solution to global warming. But a new study suggests any such efforts would present serious risks.
One of the most popular forms of geoengineering is the manipulation of clouds, using aerosols to promote cloud formation and cloud brightening. Higher concentrations of clouds -- and brighter clouds -- can help reflect sunlight and reduce warming.
The introduction of large amounts of aerosols into the atmosphere by volcanic eruptions has in the past triggered periods of global cooling.
But new analysis at the University of Exeter showed such geoengineering efforts could have unintended consequences. An influx of aerosols in the atmosphere in the Northern Hemisphere, for example, would be likely to encourage extreme droughts in the Southern Hemisphere.
Earth's climate is governed by a variety of global patterns, and changes in one part of the globe can trigger significant changes in another.
In a new paper published this week in the journal Nature Communications, scientists argue that geoengineering projects should be strictly regulated and limited in size.
"Our results confirm that regional solar geoengineering is a highly risky strategy which could simultaneously benefit one region to the detriment of another," Exeter climate scientist Anthony Jones said in a news release. "It is vital that policymakers take solar geoengineering seriously and act swiftly to install effective regulation."
Jones and his colleagues at Exeter designed complex atmosphere-ocean models to better understand how sizable aerosol injections might affect atmospheric patterns. They found aerosol injections could limit ocean warming and reduce North Atlantic tropical cyclone frequency, but could also induce severe droughts across the Southern Hemisphere.
"This research shows how a global temperature target such as 1.5 or 2 degrees Celsius needs to be combined with information on a more regional scale to properly assess the full range of climate impacts," Exeter professor Jim Haywood said.