Researchers:Dave McGuire, Eugenie Euskirchen, Clara Deal, Meibing Jin
Funding Source: NSF (IARC Cooperative Agreement)
Collaborators: Vladimir Alexeev (IARC), Vladimir Kattsov (Voeikov Main Geophysical Observatory), Peter McRoy (IARC), Nicole Mölders (Geophysical Institute), Vladimir Romanovsky (Geophysical Institute), Jingfeng Wu (IARC)
This activity will attempt to quantify the relative current and possible future influences of arctic terrestrial and marine ecosystems on the global climate system.
Our strategy in this effort is to interface with modeling groups and the other targeted activities of the IARC Cooperative Agreement in the design of a set of coordinated model experiments to elucidate the role of arctic ecosystem feedbacks in the global climate system. We will initially conduct retrospective studies with modeling tools to understand how the feedback pathways have been changing in recent decades. We will then conduct experiments with climate model runs for standard IPCC emissions scenarios identified by the research of Vladimir Kattsov. Our arctic terrestrial and marine ecosystem modeling tools will be driven by common climate forcing in the stand-alone studies, so that we can understand the relative strength of estimated responses that influence climate from terrestrial and marine ecosystems. McGuire will lead the synthesis and across all aspects of Targeted Activity 2, which includes modeling studies to investigate climate feedbacks associated with (1) responses of vegetation of high latitude terrestrial ecosystems to climate change; (2) responses of carbon dioxide; (3) responses of DMS emissions from a more ice-free Arctic Ocean; and (4) changes in the carbon dynamics of the Arctic Ocean. Euskirchen will lead the efforts on responses of vegetation and terrestrial carbon. These efforts will include collaborations involving modeling of permafrost dynamics with Vladimir Romanovsky and involving the coupling of vegetation albedo responses with the Community Climate System Model (CCSM) with collaborator Nicole Mölders. Deal and Jin of IARC will lead efforts on responses of DMS and carbon dynamics of the Arctic Ocean. These efforts will include collaborations with Peter McRoy and Jingfeng Wu on modeling marine productivity. We will work with Targeted Activity 4 (Interaction of Global Warming and Arctic Climate; collaborator Vladimir Alexeev) to evaluate the degree to which responses of Arctic Ecosystems have consequences for climate both within and beyond the Arctic.
We anticipate that some of the responses we are studying will both enhance and retard warming of the global climate system (i.e., both positive and negative feedbacks). We anticipate that responses of vegetation and DMS during the 21st Century will have greater consequences for the climate system than changes in the carbon cycle of the Arctic, but we do not currently know whether the positive feedback associated with vegetation changes will be stronger than the negative feedback associated with DMS changes. We anticipate that the combined forcings of the responses we are studying will have consequences for climate both within and beyond the Arctic.
Models of the global climate system have not effectively considered how responses of arctic ecosystems will influence the climate system. Through conducting a coordinated set of model experiments, the studies of Targeted Task 2 will provide global climate modelers information on which aspects of arctic ecosystems are most important to include in the next generation/iteration of global climate system models.