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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 tomore »conduct science. Further, participating in CCS projects excites and engages youth in science learning, regardless of the CCS program design.« less

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 metabolicmore »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.« less

Lakes set in arctic permafrost landscapes can be susceptible to rapid drainage and downstream flood generation. Of many thousands of lakes in northern Alaska, hundreds have been identified as having high drainage potential directly to river systems and 18 such drainage events have been documented since 1955. In 2018 we began monitoring a large lake with high drainage potential as part of a long‐term hydrological observation network designed to evaluate impacts of land use and climate change. In early June 2022, surface water was observed flowing over a 30‐m wide bluff, with active headward erosion of ice‐rich permafrost soils apparent by late June. This overflow point breached rapidly in early July, draining almost the entire lake within 12 h and generating a 191 m³/s flood to a downstream creek. Water level and turbidity sensors and time‐lapse cameras captured this rapid lake‐drainage event at high resolution. A wind‐driven surface seiche and warming waters following ice‐out helped trigger the initial thermomechanical breach. We estimate at least 600 MT of lake sediment was eroded, mobilized, and transported downstream. A flood wave peaking at 42 m³/s arrived 14 h after the initial breach at a river gauge 9‐km downstream. Comparing this event with three other quantified arctic lake‐drainagemore »floods suggests that lake surface area coupled with drainage gradient height can predict outburst flood magnitude. Using this relationship we estimated future flood hazards from the 146 lakes in the Arctic Coastal Plain of northern Alaska (ACP) with high drainage potential, of which 20% are expected to generate outburst floods exceeding 100 m³/s to downstream rivers. This fortunate and detailed drainage‐event observation adds to a growing body of research on the impact of lakes on arctic hydrology, hazard forecasting in a region with an increasing human footprint, and broader processes of landscape evolution in arctic lowlands.

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Abstract

Lakes are abundant features on coastal plains of the Arctic and most are termed "thermokarst" because they form in ice-rich permafrost and gradually expand over time. The dynamic nature of thermokarst lakes also makes them prone to catastrophic drainage and abrupt conversion to wetlands, called drained thermokarst lake basins (DTLBs). Together, thermokarst lakes and DTLBs cover up to 80% of arctic lowland regions, making understanding their response to ongoing climate change essential for coastal plain environmental assessment. Datasets presented here document water level and temperature (surface and ground) regimes for a large (38 sites) array of lake with high drainage potential and lake basin (DTLBS), which have already drained, located on differing terrain units of Alaska's Arctic Coastal Plain. Lake data was measured along deep protected shorelines using pressure transducers to record hourly water level and bed temperature. Wetland (DTLB) data was also measured with pressure transducers and ground thermistors at 25 and 100 centimeters (cm) depth. Of special interest at some DTLB sites was the potential occurrence of snow-dam outburst events during the early summer snowmelt periods. In these cases, pressure transducers were set to log at 10 minute intervals for this period. All data archived here are summarized at daily average values.
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Abstract

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 12 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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Abstract

This data set covers the younger outer coastal plain north of Teshekpuk Lake, North Slope, Alaska. In this region, drained lake basins are abundant features, covering large parts of the landscape. This data set is based on Landsat Thematic Mapper (TM) imagery acquired in August 2010, and a 5 meter (m) resolution Interferometric Synthetic Aperture Radar (IfSAR)-derived digital terrain model. Drained lake basins were manually delineated in a geographic information system (GIS). The data set includes Lake 195, which drained in this area in 2014. For further details please see Jones et al. (2015): Jones, BM, and Arp, CD (2015), Observing a Catastrophic Thermokarst Lake Drainage in Northern Alaska. Permafrost and Periglac. Process., 26, 119– 128. doi: 10.1002/ppp.1842.

Abstract

This data set covers the Anaktuvuk River fire site and maps drained lake basins in this area as described by Jones et al (2015). The data set is derived from airborne Light Detection and Ranging (LiDAR) data acquired in 2009 and 2014. The classification of drained lake basins is based on digital terrain models (DTMs) created from the classified LiDAR data and using the a topographic position index (TPI). The TPI output was manually categorized relative to existing surficial geology maps and refined into the following terrain units: (1) drained lake basins, (2) yedoma uplands, (3) rocky uplands, (4) glaciated upland, (5) river floodplain and (6) tundra stream gulches. The drained lake basin class is the subject of this data set publication. Jones, B., Grosse, G., Arp, C. et al. Recent Arctic tundra fire initiates widespread thermokarst development. Sci Rep 5, 15865 (2015). https://doi.org/10.1038/srep15865

Abstract. The Pleistocene sand sea on the Arctic Coastal Plain (ACP) ofnorthern Alaska is underlain by an ancient sand dune field, a geologicalfeature that affects regional lake characteristics. Many of these lakes,which cover approximately 20 % of the Pleistocene sand sea, are relativelydeep (up to 25 m). In addition to the natural importance of ACP sand sealakes for water storage, energy balance, and ecological habitat, the needfor winter water for industrial development and exploration activities makeslakes in this region a valuable resource. However, ACP sand sea lakes havereceived little prior study. Here, we collect in situ bathymetric data totest 12 model variants for predicting sand sea lake depth based on analysisof Landsat-8 Operational Land Imager (OLI) images. Lake depth gradients weremeasured at 17 lakes in midsummer 2017 using a Humminbird 798ci HD SI Comboautomatic sonar system. The field-measured data points were compared tored–green–blue (RGB) bands of a Landsat-8 OLI image acquired on 8 August2016 to select and calibrate the most accurate spectral-depth model for eachstudy lake and map bathymetry. Exponential functions using a simple bandratio (with bands selected based on lake turbidity and bed substrate)yielded the most successful model variants. For each lake, the most accuratemodel explained 81.8 % of the variation inmore »depth, on average. Modeled lakebathymetries were integrated with remotely sensed lake surface area toquantify lake water storage volumes, which ranged from 1.056×10-3 to 57.416×10-3 km3. Due to variations in depthmaxima, substrate, and turbidity between lakes, a regional model iscurrently infeasible, rendering necessary the acquisition of additional insitu data with which to develop a regional model solution. Estimating lakewater volumes using remote sensing will facilitate better management ofexpanding development activities and serve as a baseline by which toevaluate future responses to ongoing and rapid climate change in the Arctic.All sonar depth data and modeled lake bathymetry rasters can be freelyaccessed at https://doi.org/10.18739/A2SN01440 (Simpson and Arp, 2018) andhttps://doi.org/10.18739/A2HT2GC6G (Simpson, 2019), respectively.« less