Volcanos spew aerosols that act as cloud condensation nuclei which cause clouds to form. Researchers in England studied satellite images of areas downwind from an active volcano in Hawaii to develop methods of predicting how well human generated aerosols might work for Marine Could Brightening. They conclude that MCB will work best in the tropics in places with high humidity, stable air layers, and few clouds. They conclude it will work mostly by forming clouds where there are none rather than brightening existing clouds. They conclude that MCB may be more effective than previously thought.

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