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Carbon dioxide is a kind of “plant food.”

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Plants break down carbon dioxide as they make energy through photosynthesis, releasing

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oxygen in the process. That’s why as humans have increased

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the amount of carbon dioxide in the atmosphere, some places have seen increased plant growth.

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But that won’t continue forever.

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Carbon dioxide is a greenhouse gas,

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responsible for warming our planet. Right now, the land and the ocean

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about 55 percent of the carbon dioxide released by humans.

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The rest stays in the atmosphere, acting like a blanket around Earth.

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As the climate gets warmer, plants are absorbing less carbon dioxide.

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In some places, like the Arctic region,

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water is becoming scarcer, acting as a limiting factor

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that inhibits plant growth. In other places, like the tropical latitudes,

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low soil nutrients limit the growth of plants, even when there’s plenty of carbon dioxide.

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But it’s not just external factors

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that could affect how plants absorb carbon dioxide –

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as the concentration in the atmosphere increases, plants seem to use less of it.

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From 1982 to 2015, we’ve already seen

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a decrease in how efficient plants are at absorbing carbon dioxide.

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NASA researchers are using data from a variety of different satellites

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to calculate how efficient plants are at absorbing carbon dioxide.

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They’re working to understand how more carbon emissions will warm the planet

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as plants use less of it – important for understanding

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how hot Earth will get.

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NASA