Geoengineering: artificially cooling Earth has risky consequences

HAMBURG, GERMANY / ZURICH, SWITZERLAND — As temperatures on Earth reach unprecedented highs, extreme, potentially disastrous weather will be more likely. Scientists say there may be ways to intervene, but warn that they come with risky consequences.

Business Insider reports that two recently published papers in the journal Science are investigating strategies for geoengineering, which is the artificial modification of environmental processes or climate systems, as a way of combating climate change.

One such strategy is mimicking the effects of a volcanic eruption.

Erupting volcanoes spew out large amounts of sulfur-rich gases, which help cool the Earth by reflecting solar radiation back into space.

The same effect can be recreated using planes that would inject sulfur into the atmosphere. But to cool the planet by 1 degree Celsius, 6,700 injections are needed eventually, which will cost $20 billion annually.

This approach also risks destroying the ozone layer and reducing rainfall, enough to potentially cause droughts in certain regions.

A similarly drastic approach to cooling Earth can be achieved by thinning heat-trapping cirrus clouds. Seeding causes the clouds to break apart and lets more heat escape.

The seeding process, however, must be precise, otherwise new cirrus clouds may form elsewhere and add to the warming effect.

But while sulfur injections and cirrus cloud seedings will cool the land, carbon dioxide levels in the atmosphere remain the same, and ocean acidification continues.

As such, researchers argue the two strategies should be deployed more as a last resort, adding that reducing carbon emissions are much more effective at curing climate change.