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  • From thin and wispy to big and puffy,

  • clouds cover about 70% of the planet at any given moment.

  • But what if, in the next minute,

  • poof, they all disappeared?

  • That instant might shock onlooking astronauts

  • on the space station.

  • But someone who is, say, hiking in the desert

  • wouldn't know right away that things on Earth

  • were about to get really bad.

  • Within a few days, though,

  • the first warning sign would show up: humidity.

  • It'll be even worse if you live by the coast.

  • Normally, the sun's heat evaporates water,

  • mostly from the ocean,

  • and that water vapor is condensed into clouds.

  • But if clouds are cut out of the Earth's water cycle,

  • that water just hangs around in the air,

  • creating close to 100% humidity.

  • If you were to get on a flight,

  • you might experience more turbulence than usual.

  • Without the protective cover of clouds

  • to bounce sunlight into space,

  • the sun will heat the Earth more,

  • creating more rising, uneven hot air.

  • But a bad flight may be the least of our worries,

  • because there'll be no more rain

  • or snow or even a light mist,

  • and that means there won't be any way

  • to replenish the water sources we drink from,

  • like lakes, streams, rivers, springs, and aquifers.

  • So once last winter's snow melts,

  • we're stuck with whatever water we have on hand.

  • And the clock is ticking.

  • If the world were to keep up

  • its current water-consumption rate,

  • we would drain all of the freshwater lakes and rivers

  • in about 23 years.

  • So to conserve our freshwater supply,

  • humanity will have to be strategic.

  • Today, the average American uses

  • about 80 to 100 gallons of water every day.

  • But saving ourselves is going to take more

  • than just skipping long showers and laundry.

  • The water we use in our home and public places

  • accounts for only 21% of our water usage.

  • The two biggest demands are actually

  • thermoelectric power to generate electricity

  • and irrigation for farms.

  • Not only do power plants use tons of water,

  • ones that run on nuclear fuel could spell disaster

  • if their water-cooling towers run dry.

  • The 2011 Fukushima nuclear disaster, for example,

  • was set off when an earthquake knocked out power

  • to its water-cooling pumps.

  • And farms are going to need even more water

  • without the help of a good rain.

  • This permanent drought would kill

  • tons of wild vegetation and animals as the land dries up.

  • Within a few years,

  • eroding soil may kick up giant dust storms

  • like the Dust Bowl in the 1930s.

  • Meanwhile, Earth's climate will be going haywire

  • without clouds.

  • It's hard to say when this will all happen

  • without some very expensive climate modeling,

  • but cloud expert Chris Fairall

  • did offer some quick back-of-the-envelope calculations.

  • Without clouds, average surface temperatures

  • would rise by as much as 22 degrees Celsius.

  • This extreme temperature spike

  • would not only destroy the habitats of most flora and fauna,

  • killing off whatever survived the drought,

  • it would also melt the polar ice caps

  • and cause massive flooding of coastal cities.

  • You might end up being part of the 40% of the world

  • that would be forced inland,

  • and your new home might soon be in an endless desert

  • as seawater starts seeping into

  • our fresh and precious groundwater.

  • Sounds alarming, but there are some silver linings

  • to a world without clouds.

  • No more devastating hurricanes and tornadoes,

  • or delayed flights because of stormy weather,

  • or cloudy skies to ruin your stargazing.

  • As the water supply dwindles,

  • we'll have to make some hard choices,

  • but, hey, humans are creative.

  • We could invent ways to desalinate ocean water

  • or collect all that water vapor from the air.

  • And the sooner we do it, the better,

  • because in reality, we're already losing clouds.

  • Unprecedented levels of CO2

  • and the warming oceans and atmosphere

  • are all causing clouds to thin out.

  • So despite the silver linings,

  • it might be best to reduce our greenhouse gas emissions

  • and try to avoid this scary new world entirely.

From thin and wispy to big and puffy,

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B1 water earth water vapor humidity vapor freshwater

What If All The Clouds Disappeared Forever?

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    林宜悉 posted on 2021/03/01
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