When there are fewer and fewer clouds, it doesn’t make headlines as floods or fires do. Their absence is quiet, cumulative and very worrying.
To be clear, clouds aren’t going to disappear. They may increase in some areas. But the belts of shiny white clouds we need most between 1.5 and 3 per cent per decade.
These clouds are the best at reflecting sunlight back to space, especially in the sunniest parts of the world close to the equator. By contrast, broken grey clouds reflect less heat, while less light hits polar regions, giving polar clouds less to reflect.
Clouds are often thought of as an ambient backdrop to climate action. But we’re now learning this is a fundamental oversight. Clouds aren’t décor — they’re dynamic, distributed and deeply consequential infrastructure able to cool the planet and shape the rainfall patterns seeding life below. These masses of tiny water droplets or ice crystals represent climate protection accessible to all, regardless of nation, wealth or politics.
On average, clouds cover of the Earth’s surface, clustering over the oceans. Of all solar radiation reflected back to space, clouds are responsible for about 70 per cent.
Clouds mediate extremes, soften sunlight, ferry moisture and form sustaining a stable climate.