Arctic tundra is now a source – not a sink – of carbon emissions

For millennia, Arctic ecosystems have stored more carbon dioxide than they release, but that has shifted as warming temperatures have boosted wildfires and melted permafrost in the north

​For millennia, Arctic ecosystems have stored more carbon dioxide than they release, but that has shifted as warming temperatures have boosted wildfires and melted permafrost in the north For millennia, Arctic ecosystems have stored more carbon dioxide than they release, but that has shifted as warming temperatures have boosted wildfires and melted permafrost in the north