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The Arctic is experiencing warming and ecological shifts due to climate change and the compounding effects of polar amplification. Arctic Alaskan coastal marsh environments, such as the Cape Espenberg barrier beach system, offer an opportunity to determine the carbon cycle response to changing climate by examining sediment records that have been preserved through time as shoreline-parallel, linear geometry prograding geomorphic features. This study determines the carbon and mineral accumulation trends in marsh environments at Cape Espenberg for both paleo (~776 CE to 1850 CE) and modern (post-1850 CE) time frames. A comprehensive physical and chemical dataset, including radioisotope (137Cs, 210Pb, 14C), stable isotope (δ13C), element concentration (%C, %N, C:N), and dry bulk density, has been built for several sediment cores. Results indicate that carbon and mineral accumulation rates have increased from paleo to modern times, potentially because of better growing and preservation conditions for organic matter in a modern climate. Paleoclimate trends in the Medieval Climate Anomaly (MCA) and warm periods interspersed within the Little Ice Age (LIA) also correlate with greater contributions of wetland organic matter, as evidenced by lighter δ13C values. Cold climate periods within the LIA correlate with increased aquatic organic matter sourcing and heavier δ13C values, with some spikes of wetland sources interspersed throughout the LIA. Future temperatures are predicted to rise with global climate change, which may continue to expand carbon stores in Arctic coastal wetland sediments. This has been observed in the swale environments at Cape Espenberg, where increasingly favourable growing and soil-preservation conditions (i.e. wet/anoxic soils and lower salinity to limit organic material decay, higher temperatures to promote growth) are increasing the carbon storage within Arctic coastal carbon reservoirs. 

Arctic amplification of climate change has resulted in increased coastal hazards impacts to remote rural coastal communities in Alaska where conducting research can be difficult, requiring alternate methods for measuring change. The pilot program, Stakes for Stakeholders, was initially planned to be funded from 2016–2018. Upon project completion the work has shifted to individual community’s partnering with several agencies to continue the work. This research showcases a successful long-term community-based erosion monitoring program in two rural communities in Southwest Alaska. The resulting outputs from the workflow we developed were (1) locally prioritized data products, such as a hazard assessment report for Chignik Bay and (2) evaluation rubrics used to assess the suitability of future sites and the efficacy of the program. Our model of two-way communication, responsiveness to individual community needs, and attention to efficiency and effectiveness of the program workflow, can serve as a model for universities, for-profit, non-profit, Tribal, city, state, and federal research agencies and communities partnering to respond to global climate change.