A place to talk about cooling the Earth

By Oliver Morton, Senior editor, The Economist and chair, The Degrees Initiative

PROJECT POPEYE was an attempt by America to vanquish its Vietnamese enemies using cloud-seeding techniques to wash out their supply lines. It didn’t work. But a few years after the fact, in 1977, it did bring about a treaty aimed at stopping others from following suit. The “Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques”, normally known as ENMOD, prohibits countries from deliberately using “environmental modification techniques having widespread, long-lasting or severe effects” to harm each other.