Effect of climate change on greenhouse gas fluxes from marine Artic regions

ended

Current global warming is faster in the Arctic already affecting the region profoundly. In the Arctic, key players that likely have a strong impact on global warming are permafrost and gas hydrates, because both host large amounts of carbon. Permafrost and gas hydrates also likely occur offshore as relics of the Pleistocene. Current global warming may cause melting of these marine permafrost and gas hydrates and release more greenhouse gases into the ocean or even atmosphere (climatic feedback). However, the geologic processes that govern such melting and the sensitivity to climate change are poorly constrained. Here, I propose an original combination of approaches to assess the contribution of (sub-) Arctic marine gas hydrate and permafrost systems to marine geologic greenhouse gas emissions (GreenFlux). First, I will investigate the sensitivity of these marine systems and associated fluid flow systems to climate change across the NE Greenland shelf by using seismic and acoustic data in combination with paleo-oceanographic proxies from sediment cores. Second, a detailed study of the Kattegat, offshore Denmark, provides an analogue for the spatiotemporal evolution of sub-Arctic fluid flow systems in response to climatic changes. I will compare these two regions, one Arctic and one now temperate, to evaluate how the environmental differences impact gas release and how the Arctic is likely to develop in a future warmer world. GreenFlux will break new ground in our understanding of how climate change will influence marine gas hydrates, permafrost, and associated fluid flow in Arctic regions, and generate new knowledge on how much greenhouse gas these systems contribute to natural geologic emissions. The results will therefore be of importance to a wide audience, ranging from all Earth scientists to policy makers and the general public because they contribute to improvements of climatic models that help us as society predict and deal with the effects of climate change.