ultracool writes, "While the only permanent solution for human-driven global warming is developing renewable energy, a temporary hack to counteract possible abrupt climate change is to build a giant sunshade in space. The sunshade would be launched in small pieces by electromagnetic launchers, conventional chemical rockets being far too expensive. The sunshade could be developed and deployed in 25 years, would last about 50 years, and would reduce the amount of sunlight reaching Earth by 2% — enough to balance heating due to a doubling of carbon dioxide in the atmosphere." From the article: "The [trillions of] spacecraft would form a long, cylindrical cloud with a diameter about half that of Earth, and about 10 times longer... Sunlight passing through the 60,000-mile length of the cloud, pointing lengthwise between the Earth and the sun [at L-1], would be diverted away from our planet... The sunshade could be deployed by a total 20 electromagnetic launchers [collectively] launching a stack of [a million] fliers every 5 minutes for 10 years."