Scientists have warned that tackling global warming through geoengineering could have severely detrimental implications for regions prone to tumultuous storms or prolonged drought.
Injecting aerosols into the atmosphere in order to reflect sunlight before it reaches the surface of the earth has been mooted as a possible way to deal with climate change
However, a study published yesterday in the journal Nature Communications reveals the controversial practice could benefit one region to the detriment of another.
For example, injections of aerosols in the northern hemisphere would reduce tropical cyclone activity, but increase the likelihood of a drought in the Sahel at the same time.
In response, the researchers have called for strict worldwide regulation for any large-scale unilateral geoengineering to prevent natural disasters in other parts of the world.
“Our results confirm that it is a highly risky strategy,” paper lead author, Dr Anthony Jones, said. “It is vital that policymakers take solar geoengineering seriously and act swiftly to install effective regulation.”
Climate experts at the University of Exeter led the study after the idea of solar geoengineering garnered attention as a plausible method to counteract global warming.
Stratospheric aerosol injection is designed to mimic the aftermath of volcanic eruptions, when aerosols are naturally emitted into the atmosphere, and is just one proposed method of reflecting sunlight.
Others include brightening clouds by spraying seawater into the atmosphere, while it has even been suggested that giant mirrors orbiting around the earth could be used to deflect sunlight into space.
However, these methods do not remove greenhouse gases, and therefore could not address all the impacts of climate change, such as ocean acidification, while there is also a fear they could be weaponised.
In addition, these approaches are criticised for lacking control and predictability, with scientists stressing that the uncertain outcomes of these methods requires more research.
"A global temperature target such as 1.5 or 2˚C needs to be combined with information on a more regional scale to properly assess the full range of climate impacts,” study co-author, professor Jim Haywood, concluded.
