According to this scheme, a fleet of ships would be dispatched to the Arctic Ocean to shoot very fine droplets of salt water into the sky. The salt crystals, it’s theorized, would increase the clouds’ reflectivity, thus reducing the amount of sunlight striking the ice. “The hope is to preserve the layer of sea ice that is formed during the polar winter,” King said. “And if you proceed with that year on year, you rebuild the ice, layer by layer.”