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Creators/Authors contains: "Arp, Christopher"

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  1. This study introduces a new automated system that blends multi-satellite information and citizen science data for reliable and timely observations of lake and river ice in under-observed northern regions. The system leverages the Google Earth Engine resources to facilitate the analysis and visualization of ice conditions. The adopted approach utilizes a combination of moderate and high-resolution optical data, along with radar observations. The results demonstrate the system’s capability to accurately detect and monitor river ice, particularly during key periods, such as the freeze-up and the breakup. The integration citizen science data showed added values in the validation of remote sensing products, as well as filling gaps whenever satellite observations cannot be collected due to cloud obstruction. Moreover, it was shown that citizen science data can be converted to valuable quantitative information, such as the case of ice thickness, which is very useful when combined with ice extent derived from remote sensing. In this study, citizen science data were employed for the quantitative assessment of the remote sensing product. Obtained results showed a good agreement between the product and observed river status, with a Critical Success Index of 0.82. Notably, the system has shown effectiveness in capturing the spatial and temporal evolution of snow and ice conditions, as evidenced by its application in analyzing specific ice jam events in 2023. The study concludes that the developed system marks a significant advancement in river ice monitoring, combining technological innovation with community engagement. 
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  2. Youth-focused community and citizen science (CCS) is increasingly used to promote science learning and to increase the accessibility of the tools of scientific research among historically marginalized and underserved communities. CCS projects are frequently categorized according to their level of public participation and their distribution of power between professional scientists and participants from collaborative and co-created projects to projects where participants have limited roles within the science process. In this study, we examined how two different CCS models, a contributory design and a co-created design, influenced science self-efficacy and science interest among youth CCS participants. We administered surveys and conducted post-program interviews with youth participation in two different CCS projects in Alaska, the Winterberry Project and Fresh Eyes on Ice, each with a contributory and a co-created model. We found that youth participating in co-created CCS projects reflected more often on their science self-efficacy than did youth in contributory projects. The CCS program model did not influence youths’ science interest, which grew after participating in both contributory and co-created projects. Our findings suggest that when youth have more power and agency to make decisions in the science process, as in co-created projects, they have greater confidence in their abilities to conduct science. Further, participating in CCS projects excites and engages youth in science learning, regardless of the CCS program design. 
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  3. Understanding aquatic habitat and water resource responses to rapid and ongoing changes in both climate and land-use provide the basis for monitoring physical processes in ten streams and their watersheds in the northeastern portion of the National Petroleum Reserve in Alaska (NPR-A). Streams selected for monitoring were originally based on planned development in their upstream catchments and to represent reference (undeveloped) conditions. Monitoring periods for each station (up to 15 years) vary according to adaptive management of water resources in response to broader NPR-A management planning as well as alignment with proposed and ongoing monitoring efforts in Arctic Alaska. Stream discharge and water temperature data provide basic information to characterize physical regimes and variability among drainage units with respect to flood hazards, responses to land and permafrost dynamics, and connectivity and suitability of habitat for fish and other aquatic organism. Evaluating potential impacts of petroleum development primarily in the from lake water extraction, roads, and oil drilling and transport infrastructure are also an intended use of the data and reason for maintaining these monitoring stations. These data also support basic scientific studies of several National Science Foundation and U.S. Fish and Wildlife funded projects to characterize and understand the Arctic system. Data collection was primarily supported by the Bureau of Land Management. 
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  4. Land-based transport corridors and related infrastructure are increasingly extending into and across the Arctic in support of resource development and population growth, causing large-scale cumulative changes to northern socio-ecological systems. These changes include the increased mobility of people, goods and resources, and environmental impacts on landscapes and ecosystems as the human footprint reaches remote, unindustrialized regions. Arctic climate change is also generating new challenges for the construction and maintenance of these transport systems, requiring adaptive engineering solutions as well as community resilience. In this review article, we consider the complex entanglements between humans, the environment, and land transportation infrastructure in the North and illustrate these interrelations by way of seven case studies: the Baikal–Amur Mainline, Bovanenkovo Railway, Alaska–Canada Highway, Inuvik–Tuktoyatuk Highway, Alaska Railroad, Hudson Bay Railway, and proposed railways on Baffin Island, Canada. As new infrastructure is built and anticipated across the circumpolar North, there is an urgent need for an integrated socio-ecological approach to impact assessment. This would include full consideration of Indigenous knowledge and concerns, collaboration with local communities and user groups in assessment, planning and monitoring, and evaluation of alternative engineering designs to contend with the impacts of climate change in the decades ahead. 
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  5. This set of eleven lakes located in the Fish Creek Watershed in northern Alaska have been monitored for varying periods of time starting as early as 2011 as part of the Fish Creek Watershed Observatory (http://www.fishcreekwatershed.org/) and in coordination with several NSF supported projects. Lakes were primarily selected for long-term monitoring because of interest in water supply for industrial activities and corresponding ecosystem services along with dynamics related to climate change and variability. These data include basic lake attributes of water surface elevation and water temperature at the lake bed of interest to studies of water balance, aquatic habitat, and permafrost stability. In some cases, additional data or studies have been completed on some of these lakes which are reported separately in other datasets or scientific papers or reports. 
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  6. Abstract Permafrost underlies approximately one quarter of Northern Hemisphere terrestrial surfaces and contains 25–50% of the global soil carbon (C) pool. Permafrost soils and the C stocks within are vulnerable to ongoing and future projected climate warming. The biogeography of microbial communities inhabiting permafrost has not been examined beyond a small number of sites focused on local-scale variation. Permafrost is different from other soils. Perennially frozen conditions in permafrost dictate that microbial communities do not turn over quickly, thus possibly providing strong linkages to past environments. Thus, the factors structuring the composition and function of microbial communities may differ from patterns observed in other terrestrial environments. Here, we analyzed 133 permafrost metagenomes from North America, Europe, and Asia. Permafrost biodiversity and taxonomic distribution varied in relation to pH, latitude and soil depth. The distribution of genes differed by latitude, soil depth, age, and pH. Genes that were the most highly variable across all sites were associated with energy metabolism and C-assimilation. Specifically, methanogenesis, fermentation, nitrate reduction, and replenishment of citric acid cycle intermediates. This suggests that adaptations to energy acquisition and substrate availability are among some of the strongest selective pressures shaping permafrost microbial communities. The spatial variation in metabolic potential has primed communities for specific biogeochemical processes as soils thaw due to climate change, which could cause regional- to global- scale variation in C and nitrogen processing and greenhouse gas emissions. 
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