Over parts of Antarctica, there is an interesting negative greenhouse effect.

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Rising concentrations of methane and carbon dioxide have created a “negative greenhouse effect” over parts of Antarctica, but this slight cooling effect may be reversed as the air becomes more humid as temperatures rise.

Greenhouse gases such as CO2 and methane warm the planet by trapping radiation from its surface. However, in some unusual circumstances they can have a cooling effect, where the atmosphere expels more heat from its warm upper layers into space than is trapped near the…