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  • The earth has an elegant cycle of life.

  • It's the story of carbon.

  • And over billions of years, it has evolved to look something like this.

  • It starts with a plant.

  • Plants and microorganisms absorb carbon dioxide from the atmosphere.

  • Then they use energy from the sun to convert that carbon into oxygen and sugar, which they use to grow.

  • And as they grow, they emit some carbon back into the atmosphere.

  • But all plants eventually die.

  • And some are consumed by bacteria, others by larger beasts.

  • These animals eat plants for energy.

  • And they breathe out carbon.

  • But eventually, those animals die, too.

  • And they end up in the ground.

  • Meanwhile, a similar thing happens in the ocean.

  • Coral and plankton need carbon from the water to survive.

  • Luckily, the ocean has carbon because it absorbs some from the atmosphere.

  • And, when rain falls to the earth, it grabs some carbon from the atmosphere and from rocks.

  • And flows into the ocean, where the coral and plankton use carbon to grow.

  • Or other animals use it to grow.

  • But just like animals, the coral and plankton die, too.

  • In short, all living things are made of carbon, and they eventually end up in the ground.

  • Some of that carbon will eventually get back to the atmosphere.

  • But some of it normally stays in the ground.

  • Usually, dead things decay and turn into rocks.

  • Eventually, they're crushed, and extreme heat and pressure causes them to melt and emit the carbon, which is trapped underground.

  • Over time, that trapped carbon eventually escapes into the atmosphere when volcanoes erupt.

  • And the cycle starts again.

  • But occasionally, dead plants and animals don't turn into rock.

  • They don't decay fast enough, so they turn into oil, coal, or natural gas.

  • This carbon gets stuck in the ground.

  • This is the elegant system that keeps carbon cycling through Earth at a steady pace.

  • Carbon in the atmosphere keeps some heat from leaving Earth.

  • It keeps Earth at a stable temperature.

  • But very recently, one of these animals started to dig up the carbon in the ground.

  • They took the carbon that was stuck in the ground and put it back into the atmosphere.

  • They did this so much, in such a short time span, that this cycle was disrupted.

  • Too much carbon was being put into the atmosphere.

  • Heat that would normally be able to escape bounced back and stayed on Earth.

  • And Earth started to get warmer and warmer.

  • Really recently, just a few months ago, more than 100 bipedal scientists said they might only have 12 years to stop a disastrous amount of warming.

  • So these animals not only need to stop putting carbon in the atmosphere, but also get carbon out of the atmosphere.

  • They found that one way to remove carbon is to grow more plants.

  • They could stop cutting down trees.

  • Or raise livestock in ways that help restore grass.

  • Another way is to let plants suck up carbon from the atmosphere but then burn them for energy.

  • And then trapping the carbon they emit underground.

  • They could also build machines to suck air from the atmosphere and filter out the carbon.

  • But they haven't figured out how to do this fast enough.

  • There are many ways these animals can tweak this cycle to suck carbon out of the atmosphere.

  • A combination of them is probably the best way forward.

  • But, first, these animals need to figure out how to stop putting it there in the first place.

The earth has an elegant cycle of life.

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B1 US Vox carbon atmosphere earth cycle plankton

How humans disrupted a cycle essential to all life

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    Jessieeee posted on 2019/04/25
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