A controversial theory proposes mimicking volcanoes to fight global warming. But throwing sulfur particles into the sky may do more harm than good, a new study says.

The temporary solution would pump particles of sulfur high into the atmosphere—simulating the effect of a massive volcano by blocking out some of the sun’s rays.

This intervention, advocates argue, would buy a little time to reduce greenhouse gas emissions. But as well as cooling the planet, the sulfur particles would reduce rainfall and cause serious global drought, a new study says.