Permafrost is frozen soil that has preserved things such as ancient animal bones and centuries-old icebergs. Permafrost contains twice as much carbon as is currently in Earth's atmosphere and it also preserves old bacteria. When it's defrosted the bacteria eats dead plants and animals turning their carbon into gases such as carbon dioxide. As the permafrost warms, the microbes are releasing gases contributing to further warming. Listen to learn more about this warming cycle.
Story Length: 6:21
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