Scientists worry humans might not curb carbon emissions in time to save the planet from irreversible harm, and some have suggested a radical concept called geo-engineering, the Economist reports. Once the stuff of science fiction, geo-engineering would combat global warming by manipulating the environment. While promising, critics warn ecological consequences could be disastrous and might encourage nations to continue using fossil fuels.
One proposal suggests increasing the number of plankton, which feed on carbon dioxide and then carry it to the ocean floor. A more controversial idea involves polluting the stratosphere with planes to reflect solar rays that cause the greenhouse effect. But a UN scientific panel warns geo-engineering is “largely speculative and unproven, and with the risk of unknown side-effects.”