Climate security

Geoengineering Wouldn't Be Enough to Stop Greenland From Melting

When the Greenland ice sheet went into a record meltdown in the summer of 2019, it raised a very terrifying specter of the future. Here was a 12.5-billion-ton mass of ice—one that’s been melting at a quickening pace since the 1980s—melting in a way scientists didn’t expect to happen for decades.

While the ice sheet won’t completely disappear for centuries, any further increase in its melt will put coastal communities at risk of inundation. There’s an argument to be made that we should do everything possible to save the ice, and a new study explores a very controversial idea to that end: cooling the planet.

The findings, published last month in Earth’s Future, explore what would happen if the world pumped particles high into the atmosphere that would reflect sunlight back into space. This high-altitude air conditioning scheme, known as solar radiation management or SRM, would bring down the global average temperature. The paper’s results show that cooling would help slow—though not stop—the melting of the ice sheet. That could buy coastal regions time but also change the climate in other ways that may end up hurting other regions around the world.