Collaborative Research: Tracking Carbon, Water, and Energy Balance of the Arctic Landscape at Flagship Observatories in Alaska and Siberia

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The Arctic is warming faster than other parts of the world and it has the potential to amplify global warming. The amplification comes from thawing permafrost (frozen soils) that release greenhouse gases, especially carbon dioxide and methane, that lead to additional warming, more thaw, and more greenhouse gases released. However, how fast the permafrost will thaw, how much greenhouse gas will be released, and how important gradual thaw is versus abrupt thaw caused by melting ground ice or floods, is unknown. This Arctic Observing Network research will document changes in permafrost thaw, greenhouse gas releases, and energy balance in terrestrial and freshwater systems in the Alaskan and Russian Arctic. Arctic ecosystems have seen an acceleration of permafrost thaw and greenhouse gas release to the atmosphere that may not be easily reversed. Further observations are required to determine the rates of change and potential impacts on climate to best inform society on what to expect and how to prepare. In addition to advancing understanding of environmental change, broader impacts of the research include contributions to teaching, learning, and outreach by including findings in school classrooms, support of undergraduate summer research, and outreach to Indigenous communities and K-12 schools in Alaska. Two communities in the Alaskan and Russian Arctic will learn to map methane bubbling hotspots that create dangerous ice, which will result in co-production of knowledge and improved safety for winter travelers. Other benefits to society include improved understanding of how permafrost thaw threatens roads and buildings, and how a thawing Arctic influences climate change at lower latitudes.This research will extend time-series data on carbon, water, and energy balance in four different tundra ecosystems in northern Alaska (year-round eddy covariance measured since 2007), and at two sites in Cherskii, Russia. The records already collected show evidence of recent change and tipping points, highlighting the value of supporting long-term measurements. In addition, carbon dioxide and methane fluxes measured by eddy covariance and ebullition will be monitored in a new thermokarst lake in Siberia, and ebullition will be measured on existing and new Alaskan and Siberian lakes mapped using remote sensing. Long-term monitoring of hydrology and stream chemistry of Imnavait Creek, Alaska, and depth of thaw in its catchment will be maintained and expanded. To help interpret these core data, the project will continue camera records of plant phenology and dates of snowmelt and snow return, harvests to assess plant biomass and net primary productivity, and analysis of soil properties and stocks of carbon and nitrogen. Permafrost boreholes will be instrumented near eddy covariance towers at Imnavait Creek and near the new lake in Cherskii. All data will continue to be made publicly available and archived with the Arctic Data Center, NSF-LTER Data Portal, and Ameriflux. Data collected by this project will be used extensively by other researchers and incorporated into other observing networks such as Ameriflux, the Phenocam Network, and other efforts including NASA projects and satellite campaigns. Research will also be disseminated though scientific publications and presentations.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.