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As the Arctic warms, some of its lakes are bubbling…

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Earth’s warming climate is thawing permafrost – the Arctic’s permanently frozen layer of soil.

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As the permafrost thaws, microbes in the soil wake up and begin consuming once-frozen organic material.

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This process releases carbon dioxide and methane into the atmosphere.

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Scientists have known about this source of atmospheric carbon – a greenhouse gas – for some time.

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They have predictions about how long it will take for the carbon stored in permafrost to reach the atmosphere.

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Newly forming lakes in the region can throw a wrench in these predictions. Called thermokarst lakes, they form where thawed permafrost causes the ground to slump.