Buried danger
There is climate danger lurking under the planet's frozen wastelands. In the northern tundra, vast amounts of carbon are locked up in layers of frozen soil called permafrost.
As temperatures rise and the permafrost thaws, carbon stored over thousands of years could be released in the form of greenhouse gases.
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Permafrost (shown in purple) covers huge expanses of the North
International Permafrost Association |
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