A new study shows that carbon released during the winter now outweighs the summertime gains, resulting in a net loss of carbon to the atmosphere suggesting the northern tundra may be shifting from its historical role as a carbon sink to a carbon source.

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A new study shows that carbon released during the winter now outweighs the summertime gains, resulting in a net loss of carbon to the atmosphere suggesting the northern tundra may be shifting from its historical role as a carbon sink to a carbon source.