Climate engineering may better protect coral reefs

When it comes to protecting coral reefs from rising seawater temperature, climate engineering could be a better method than conventional carbon dioxide (CO2) mitigation strategies, new research says.

Geoengineering of the climate may be the only way to save coral reefs from mass bleaching which increases coral mortality risk, the researchers noted.

Coral reefs are considered one of the most vulnerable ecosystems to future climate change due to rising sea surface temperatures and ocean acidification, which is caused by higher atmospheric levels of carbon dioxide (CO2).

The geoengineering technique called Solar Radiation Management (SRM) reduces the risk of global severe coral bleaching, the researchers noted.

The SRM method involves injecting gas into the stratosphere, forming microscopic particles which reflect some of the sun's energy and so help limit rising sea surface temperatures.

"Coral reefs face a dire situation regardless of how intensively society decarbonises the economy," said co-author of the research Peter Cox, professor at University of Exeter in Britain.

"In reality there is no direct choice between conventional mitigation and climate engineering but this study shows that we need to either accept that the loss of a large percentage of the world's reefs is inevitable or start thinking beyond conventional mitigation of CO2 emissions," Cox noted.

The study compared a hypothetical SRM geoengineering scenario to the most aggressive future CO2 reduction strategy considered by the Intergovernmental Panel on Climate Change (IPCC), and found that coral reefs fared much better under geoengineering despite increasing ocean acidification.

The study was published in scientific journal, Nature Climate Change.