The unmanned ships would be directed by satellite to areas with the best conditions for increasing cloud cover.
From The Telegraph:
Ships with giant funnels which travel the world's seas creating more clouds to deflect the sun's rays could help cut global warming, say scientists.
The "cloud ships" are favoured among a series of schemes aimed at altering the climate which have been weighed up by a leading think-tank.
The project, which is being worked on by rival US and UK scientists, would see 1,900 wind-powered ships ply the oceans sucking up seawater and spraying minuscule droplets of it out through tall funnels to create large white clouds.
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