Organic Matter Runoff and its Fate in a Warming Arctic (ArcticOM)

Dramatically rising temperatures in the Arctic and consequent thaw of permafrost soils lead to a growing exposure of organic matter (OM) and its carbon (OC) to the hydrological cycle and increasing fluxes from rivers to the Arctic Ocean. Declining sea ice extent and shorter ice-cover period open new pathways for OC transport that may boost climate change positive feedback mechanisms. For example, increasing OM in surface water enhances radiative warming, which accelerates sea ice melt, which, in turn, opens new pathways for OC transport.

The project “Organic Matter Runoff and its Fate in a Warming Arctic” (ArcticOM) led by Bennet Juhls, aims to quantify pan-Arctic fluxes of organic carbon from land to sea. The CCI Ocean Colour (https://climate.esa.int/en/projects/ocean-colour/) dataset that covers >20 years will be used to identify potential trends that might be related to the strong warming of the Arctic. As a second objective, long-term datasets such as the permafrost temperature and the depth of the active layer from the Permafrost CCI (https://climate.esa.int/en/projects/permafrost/) will be used to address terrestrial drivers that trigger interannual and long-term changes in the transport of organic carbon to the Arctic Ocean. Overall, this project will provide new insights into the current trajectory of organic carbon mobilization from thawing permafrost, which is important to understand its potential impact on the global carbon cycle.

Research Fellow: Bennet Juhls

Host Institute: Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Permafrost Section, Potsdam, Germany