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As part of NSF Project 1848542, we assessed the impacts of Bering Sea storms on western Alaskan communities, focusing on Goodnews Bay and St. Paul Island. Field campaigns collected high-resolution coastal datasets to document storm-driven flooding and shoreline change. Cross-shore profiles were surveyed using a Trimble real-time kinematic global navigation satellite system (RTK-GNSS), extending from upland features to the waterline and repeated over time to capture coastal change. High-water marks (HWMs) were also recorded, providing elevation data for present and historic flooding events, including detailed measurements of Typhoon Merbok impacts in 2022. Indicators such as debris lines, seed lines, foam lines, and wet/dry lines were used to approximate total water levels, which integrate astronomical tide, storm surge, and wave runup. This dataset contains supporting tables and measurements from these surveys, which complement a broader assessment of storm flooding impacts on regional infrastructure. We encourage researchers to contact us with questions or requests for additional data. 

Abstract Khovanov homology has been the subject of much study in knot theory and low dimensional topology since 2000. This work introduces a Khovanov Laplacian and a Khovanov Dirac to study knot and link diagrams. The harmonic spectrum of the Khovanov Laplacian or the Khovanov Dirac retains the topological invariants of Khovanov homology, while their non-harmonic spectra reveal additional information that is distinct from Khovanov homology. 

This dataset documents the location and characteristics of 185 exotic tundra boulders found on the North Slope of Alaska, spanning observations from 1826 to 2025. These boulders—scattered across coastal tundra, estuarine margins, and barrier islands—represent a persistent but enigmatic feature of the Arctic landscape. Their lithologies, which include granite, quartzite, diabase, dolomite, chert, and gneiss, are exotic to the region and are widely interpreted to be ice-rafted debris deposited during Pleistocene highstands of the Arctic Ocean. Spatial and lithologic patterns suggest an origin in the Canadian Arctic Archipelago and Mackenzie River basin, transported westward by sea ice or icebergs during glacial periods. The dataset integrates georeferenced boulder locations from early exploration accounts (e.g., Leffingwell 1919; Stefansson 1910, Franklin and Richardson 1828), mid-century field surveys (MacCarthy 1958), geologic interpretations of offshore facies and provenance (Rodeick 1979) and USGS (U.S. Geological Survey) engineering geological maps (1980s), and modern field observations from the 2000s–2020s. Boulder characteristics—such as lithology, surface striations, and faceting—are included where available. These observations contribute to understanding of likely saline permafrost distribution, Arctic coastal dynamics, sea-level history, and the paleogeography of iceberg and sea-ice transport. They also provide a rare terrestrial window into ice-rafted sedimentation processes typically studied in marine environments. All data are curated in a comma separated spreadsheet with associated metadata to support future geomorphological, paleoclimatic, and sea-level modeling studies. The complete list of references is provided below: Barnes, P.W., 1982. Marine Ice-Pushed Boulder Ridge, Beaufort Sea, Alaska. ARCTIC 35, 312–316. https://doi.org/10.14430/arctic2330 Brigham, O.K., 1985. Marine stratigraphy and aaino-acid geochronology of the Gublk Fomatlon, western Arctic Coastal Plain, Alaska. USGS Open File Report 381. Dease, P.W., Simpson, T., 1838. An Account of the Recent Arctic Discoveries by Messrs. Dease and T. Simpson. The Journal of the Royal Geographical Society of London 8, 213–225. Franklin, J., Richardson, J., 1828. Narrative of a Second Expedition to the Shores of the Polar Sea, in the Years 1825, 1826, and 1827. Carey, Lea and Carey. Gibbs, A.E., Richmond, B.M., 2009. Oblique aerial photography of the Arctic coast of Alaska, Nulavik to Demarcation Point, August 7-10, 2006. US Geological Survey. Hopkins, D.M., Hartz, R.W., 1978. Coastal morphology, coastal erosion, and barrier islands of the Beaufort Sea, Alaska. US Geological Survey,. Jorgenson, M.T., 2011. Coastal region of northern Alaska, Guidebook to permafrost and related features (No.GB 10). Alaska Division of Geological and Geophysical Surveys. https://doi.org/10.14509/22762 McCarthy, G.R., 1958. Glacial Boulders on the Arctic Coast of Alaska. ARCTIC 11, 70–85. https://doi.org/10.14430/arctic3734 Naidu, A., Mowatt, T., 1992. Origin of gravels from the southern coast and continental shelf of the Beaufort Sea, Arctic Alaska, in: 1992 International Conference on Arctic Margins Proceedings Programs with Abstracts. pp. 351–356. O’Sullivan, J.B., 1961. Quaternary geology of the Arctic Coastal Plain, northern Alaska: Ames, Iowa, Iowa State University of Science and Technology, Ph.D. dissertation, 191 p., illust., maps. Iowa State University. Rawlinson, S.E., 1993. Surficial geology and morphology of the Alaskan central Arctic Coastal Plain (No. RI 93-1). Alaska Division of Geological and Geophysical Surveys. https://doi.org/10.14509/2484 Reimnitz, E., Ross, R., 1979. Lag deposits of boulders in Stefansson Sound, Beaufort Sea, Alaska (No.79–1205), Open-File Report. U.S. Geological Survey,. https://doi.org/10.3133/ofr791205 Rodeick, C.A., 1979. The origin, distribution, and depositional history of gravel deposits on the Beaufort Sea Continental Shelf, Alaska (No. 79–234), Open-File Report. U.S. Geological Survey,. https://doi.org/10.3133/ofr79234 Schrader, F.C., Peters, W.J., 1904. A reconnaissance in northern Alaska across the Rocky Mountains, along Koyukuk, John, Anaktuvuk, and Colville Rivers, and the Arctic coast to Cape Lisburne, in 1901, with notes (USGS Numbered Series No. 20), Professional Paper. U.S. Geological Survey, Washington, D.C. https://doi.org/10.3133/pp20 Simpson, 1855. Observations on the western Esquimaux and the country they inhabit?: from notes taken during two years at Point Barrow | CiNii Research [WWW Document]. URL https://cir.nii.ac.jp/crid/1130000795332231552 (accessed 6.10.23). Smith, P.S., Mertie, J.B., 1930. Geology and mineral resources of northwestern Alaska. USGS Report 1. Stefansson, V., 1910. Notes from the Arctic. Am. Geogr. SOC. Bull 42, 460–1. Williams, J.R., 1983. Engineering-geologic maps of northern Alaska, Wainwright quadrangle (No. 83–457), Open-File Report. U.S. Geological Survey. https://doi.org/10.3133/ofr83458 Williams, J.R., Carter, L.D., 1984. Engineering-geologic maps of northern Alaska, Barrow quadrangle (No.84–124), Open-File Report. U.S. Geological Survey. https://doi.org/10.3133/ofr84126 Williams, R.J., 1983. Engineering-geologic maps of northern Alaska, Meade River quadrangle (No. 83–294), Open-File Report. U.S. Geological Survey. https://doi.org/10.3133/ofr83325 Wolf, S.C., Reimnitz, E., Barnes, P.W., 1985. Pleistocene and Holocene seismic stratigraphy between the Canning River and Prudhoe Bay, Beaufort Sea, Alaska. US Geological Survey,. de Koven Leffingwell, E., 1908. Flaxman Island, a Glacial Remnant. The Journal of Geology 16, 56–63. https://doi.org/10.1086/621490 de Koven Leffingwell, E., 1919. The Canning river region, northern Alaska (No. 109). US Government Printing Office. 

Ice wedges, which are ubiquitous in permafrost areas, play a significant role in the evolution of permafrost landscapes, influencing the topography and hydrology of these regions. In this paper, we combine a detailed multi-generational, interdisciplinary, and international literature review along with our own field experiences to explore the development of low-centered ice-wedge polygons and their orthogonal networks. Low-centered polygons, a type of ice-wedge polygonal ground characterized by elevated rims and lowered wet central basins, are critical indicators of permafrost conditions. The formation of these features has been subject to numerous inconsistencies and debates since their initial description in the 1800s. The development of elevated rims is attributed to different processes, such as soil bulging due to ice-wedge growth, differential frost heave, and the accumulation of vegetation and peat. The transition of low-centered polygons to flat-centered, driven by processes like peat accumulation, aggradational ice formation, and frost heave in polygon centers, has been generally overlooked. Low-centered polygons occur in deltas, on floodplains, and in drained-lake basins. There, they are often arranged in orthogonal networks that comprise a complex system. The prevailing explanation of their formation does not match with several field studies that practically remain unnoticed or ignored. By analyzing controversial subjects, such as the degradational or aggradational nature of low-centered polygons and the formation of orthogonal ice-wedge networks, this paper aims to clarify misconceptions and present a cohesive overview of lowland terrain ice-wedge dynamics. The findings emphasize the critical role of ice wedges in shaping Arctic permafrost landscapes and their vulnerability to ongoing climatic and landscape changes. 

This dataset documents changes in infrastructure development and associated ice wedge thermokarst formation in Point Lay (Kali), Alaska, between 1949 and 2020. The data include vector-based Geographic Information System (GIS) layers derived from high-resolution remote sensing imagery and historical aerial photographs for three key time points: 1949, 1974, and 2019/20. Infrastructure features (e.g., roads, runways, gravel pads, and buildings) were manually digitized, and the extent of ice wedge thermokarst was mapped using detailed image interpretation techniques at 1:500 scale. The dataset supports spatial analysis of thermokarst expansion in relation to anthropogenic disturbance and surface development. Findings reveal a near tenfold increase in ice wedge thermokarst extent in developed areas between 1974 and 2019, with minimal changes in adjacent undisturbed tundra, underscoring the synergistic impact of infrastructure and climate warming on permafrost degradation. These data provide a valuable baseline for tracking permafrost-related landscape changes and informing adaptation strategies in Arctic communities experiencing thaw-related infrastructure challenges. 

This dataset provides a comprehensive, field-validated Synthetic Aperture Radar (SAR) dataset for Arctic lake ice classification, with a particular emphasis on under-ice water salinity. It includes in situ measurements from 104 lakes (132 measurement sites) across northern Alaska collected in May 2024, capturing data on lake ice thickness, snow depth, lake depth, and specific conductance of unfrozen water beneath the ice. These field observations are integrated with multi-season Sentinel-1 SAR imagery from early winter (January) to late winter (May), along with additional geospatial datasets such as Interferometric Synthetic Aperture Radar (IfSAR)-derived elevation models and summer ice-off timing. The dataset enables improved differentiation of bedfast and floating ice lakes, particularly identifying lakes with brackish to saline water that were previously misclassified as bedfast ice lakes using traditional SAR-based remote sensing approaches. This resource supports research in permafrost stability, Arctic hydrology, climate change impacts, and winter water resource availability. This work was supported by grants from the U.S. National Science Foundation (OPP-2336164 and OPP-2336165) and the European Research Council project No. 951288 (Q-Arctic). Additional support was provided under a Broad Agency Announcement award from ERDC-CRREL, PE 0603119A. 

This dataset contains orthomosaics, digital surface models (DSMs), and multispectral image composites for nine Arctic Beaver Observation Network (ABON) sites surveyed in August 2024. The data were collected to support research on the impacts of beaver engineering on tundra hydrology, vegetation, and permafrost dynamics across Arctic Alaska. Drone-based imagery was acquired using a DJI Mavic 3 Multispectral quadcopter equipped with a DJI D-RTK 2 Mobile Base Station for real-time kinematic (RTK) positioning. At each site, flight missions were conducted at 120 meters (m) above ground level with 80% along-track and 70% across-track overlap, using a nadir-oriented camera (90°) and the hover-and-capture-at-point mode. The resulting products include: (1) (Red, Green, Blue) RGB orthomosaics with a ground sampling distance of 5 centimeters (cm), (2) Digital Surface Models (DSMs) with 10 cm spatial resolution, and (3) multispectral composites (green, red, red edge, near-infrared bands) at 10 cm resolution. Radiometric calibration was performed using images of a MicaSense calibrated reflectance panel, and a Leica Viva differential global positioning system (GPS) provided ground control for the mission and the data were post-processed to WGS84 UTM Zone 3 North. All images were processed in Pix4D Mapper (v. 4.10.0). Elevation information derived over waterbodies is noisy and does not represent the surface elevation of the feature. These high-resolution datasets provide baseline observations of beaver pond morphology and vegetation dynamics, enabling long-term monitoring of ecosystem changes driven by beaver activity in Arctic tundra landscapes. 

To assess coastal erosion dynamics during the entire 2018 and 2019 open water seasons at Drew Point, Beaufort Sea Coast, Alaska, we derived 16 coastlines position using satellite, airborne and unmanned aerial vehicle (UAV) sensors. Sensors with associated image dates are: Worldview 1 imagery ©Maxar (14 April 2019), Worldview 2 panchromatic imagery ©Maxar (5 April 2019, 26 September 2019, and 3 April 2020); Modular Aerial Camera System (MACS-Polar) during the Polar-6 airborne operations during the ThawTrend-Air campaign (13 July 2019, 23 July, 2019, and 30 July 2019) and DJI Phantom 4 UAV surveys (24 July 2018, 29 July 2018, 3 August 2018, 30 September 2018, 2 August 2019, 6 August 2019, 10 August 2019, 12 August 2019 and 15 August 2019). Pixel resolution for the satellite, airborne and UAV imagery was 50 cm (Worldview 1), 46 centimeter (cm) (Worldview 2), 10 cm and 4 cm, respectively. The satellite-image derived coastlines span the 9 kilometer (Km) segment described in Jones et al. (2018; DOI: 10.1088/1748-9326/aae471), while the other coastline spans a 1.5 Km sub-section of the study area that includes the coastline, part of inland coastal area (~125 meters (m)) and fallen toppled permafrost blocks in front of the bluff. Fallen toppled permafrost blocks were digitized using the airborne and UAV images. The satellite imagery was too coarse to digitize blocks. All datasets are in WGS84 UTM Zone 5N. 

To assess coastal erosion dynamics during the 2018 and 2019 open water seasons at Drew Point, Beaufort Sea Coast, Alaska, we generated orthomosaic images and associated digital surface models from 9 unmanned aerial vehicle (UAV) surveys. UAV surveys were collected on 24 July 2018, 29 July 2018, 3 August 2018, 30 September 2018, 2 August 2019, 6 August 2019, 10 August 2019, 12 August 2019 and 15 August 2019. The digital surface models elevations are at relative sea level (2.2 meters (m) higher than local ellipsoid heights) and have been cleaned up (i.e. noise from waves removed) to only include the coast edge, ~125 m inland from the coast and toppled permafrost blocks in front of the bluff edge.