Efforts to cool the planet with sunlight reflecting technologies may not shield much of the world’s oceans from dangerous heat, according to new research that challenges one of the most widely discussed ideas in climate engineering.
By Nympha Ozougwu, OPA News Agency
Debate has intensified among climate scientists over whether solar geoengineering can offer fair protection for the oceans, after modelling showed that cooling the planet does not cool all regions equally.
Researchers at Michigan State University examined how interventions such as stratospheric aerosol injection could influence marine heatwaves, which threaten fisheries, coral reefs and coastal economies.
They found that under a moderate deployment scenario, only about a quarter of the global ocean would be protected from worsening heatwaves. Even stronger interventions left large areas exposed, with nearly 25 percent of the oceans still facing longer and hotter events.
“The degree of protection depends on how aggressively it is deployed,” said oceanographer Lala Kounta. She added that “the geography of protection is deeply unequal.”
Some of the least responsive regions include parts of the North Atlantic, the Pacific and the Southern Ocean, where natural variability and circulation patterns can sustain or redistribute heat even when global temperatures fall.
The researchers also stress that these approaches do not remove greenhouse gases from the atmosphere. They work by reducing incoming solar radiation, which does not address the underlying driver of warming from accumulated carbon dioxide.
Geoengineering itself is not new. Countries have experimented with weather modification for decades.
China has used cloud seeding to influence rainfall during major events, while the United Arab Emirates has run regular cloud seeding flights to boost rainfall in its arid interior. In the United States, cloud seeding has been used in parts of Colorado and Wyoming to increase snowfall for water supply.
These efforts are small compared with proposals to cool the entire planet, but they show how governments have long explored ways to alter weather when faced with rising climate pressures.
Marine heatwaves have become more frequent since the 1980s, driven by rising ocean heat content as the seas absorb more than 90 percent of excess heat trapped by greenhouse gases. Recent years have brought major impacts, including global coral bleaching events in 2016 and again in the early 2020s that caused widespread damage to reef ecosystems.
The findings add to a growing body of research suggesting that even if solar geoengineering is deployed, it may not offer uniform protection for the world’s oceans, raising questions about who benefits and who remains exposed.
One Planet Agency
