A third of the Arctic’s vast carbon sink now a source of emissions, study reveals

Critical CO2 stores held in permafrost are being released as the landscape changes with global heating, report shows

For millennia, Arctic land ecosystems have acted as a deep-freeze for the planet’s carbon, holding vast amounts of potential emissions in the permafrost. File photo: Andy Clark

A third of the Arctic’s tundra, forests and wetlands have become a source of carbon emissions, a new study has found, as global heating ends thousands of years of carbon storage in parts of the frozen north.

For millennia, Arctic land ecosystems have acted as a deep-freeze for the planet’s carbon, holding vast amounts of potential emissions in the permafrost. But ecosystems in the region are increasingly becoming a contributor to global heating as they release more CO2 into the atmosphere with rising temperatures, a new study published in Nature Climate Change concluded.