New PCIC Science Brief

PCIC  is pleased to announce the release of our newest Science Brief. This Science Brief covers a recent paper in Nature Climate Change by Natali et al. that uses a machine learning model to investigate winter (October through the end of April) carbon dioxide emissions in the Arctic, over the 2003-2017 period and in future projections. The authors use in-situ observations of CO₂ flux from Arctic and Boreal permafrost soil to create a model that allows them to estimate winter soil carbon flux over the 2003-2017 period. They also drive their model with global climate model output, to make projections of future CO₂ flux in the region. They estimate that approximately 1.7 gigatonnes of carbon (GtC) were released each winter over the 2003-2017 period. The authors also find that, of the variables that they tested, soil temperature had the largest relative influence on CO₂ flux. Their projections show future winter Arctic soil fluxes of about 2.0 GtC per year by 2100, for a moderate emissions scenario, and about 2.3 GtC per year, assuming a high-emissions scenario.

As the Arctic warms, the rate at which microbes in Arctic soil digest soil organic matter increases and, with it, the release of carbon dioxide into the atmosphere also increases. The amount of carbon released into the atmosphere from permafrost in this region is significant and so it is important to measure it accurately and be able to make credible projections of it.

Read the latest Science Brief.

Natali, S.M., et al., 2019: Large loss of CO2 in winter observed across the northern permafrost region. Nature Climate Change, 9, 852–857, doi:10.1038/s41558-019-0592-8