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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 the occurrence, distribution, and characteristics of cryptic ice wedge networks in the Yukon-Kuskokwim Delta (YKD), Alaska. The dataset is derived from remote sensing analyses, field-based permafrost coring, ground-penetrating radar (GPR) surveys, and stable water isotope analyses. High-resolution aerial orthoimagery from 2018 enabled the identification of ~50 linear kilometers (km) of ice wedge trough networks within a 60 square kilometers (km²) study area near Bethel, Alaska, revealing ice wedge networks previously undocumented in the region. Fieldwork in 2023 and 2024 confirmed the presence of ice wedges up to 1.5 meter (m) wide and 2.5 m tall, with wedge tops averaging 0.9 m below the surface. GPR transects identified additional ice wedges beyond those visible in imagery, suggesting that remote sensing analyses may underestimate their true abundance. Coring of polygon centers revealed a suite of late-Quaternary deposits, including early Holocene peat, ice-rich late-Pleistocene permafrost (reworked Yedoma), charcoal layers indicating past tundra fires, and the Aniakchak CFE II tephra (~3,600 calendar years before present [cal yrs BP]). Stable water isotope analyses of wedge ice (mean δ¹⁸O = -15.7 ‰, δ²H = -113.1 ‰) indicate relatively enriched values compared to other Holocene ice wedges in Alaska, reflecting the region's warm maritime climate influence. Expanding the mapping analysis across the YKD using very high-resolution satellite imagery, we found that 95 % of observed ice wedge networks occur at elevations between 4 and 80 meters above sea level (m asl), predominantly within tundra vegetation classes. These areas, covering ~32 % of the YKD tundra region, may contain additional ice wedges, peat deposits, and relict Yedoma. This dataset provides a new framework for understanding the spatial distribution and environmental controls on ice wedge development in warm permafrost regions, with implications for permafrost resilience, climate change vulnerability, and land use planning in the YKD. 

This database contains data on site, soil stratigraphy, soil physical and chemical properties, Carbon-14 (C14) and stable isotope, and vegetation composition and structure acquired from permafrost soil surveys and thermokarst monitoring sites. The data are from projects that we have conducted, as well as data compiled from numerous other project and reports, that have emphasized the study of the intermediate layer of upper permafrost and the dynamic responses of permafrost to environmental conditions. This 2023 update includes data from our recent National Science Foundation (NSF)-funded project on the upper permafrost. The Access Database has 11 main data tables (tbl_) for site (environmental), soil stratigraphy, soil physical data, soil chemical data, water Oxygen-18 (O18), soil radiocarbon dates, vegetation cover, vegetation structure, study areas, personnel, and project data sources. The Site data includes information of location, observers, geomorphology, topography, hydrology, soil summary characteristics, pH and electrical conductivity (EC), soil classification, and vegetation cover by species. Soil stratigraphy has information on soil texture and ground ice. Soil physical and chemical data includes lab data on bulk density, moisture, carbon, and nitrogen. The database has 40 reference tables (REF_) that have codes and descriptions for variables used in site, soil stratigraphy, and vegetation cover tables. Query tables (qry_) are used to link data tables and reference tables to display data with names instead of codes. In addition to the permafrost soils information, the Site data includes topographic survey control information for repeat monitoring of thermokarst study areas. The data and metadata are provided in three formats. The Access relational database has all the data and reference tables, as well as the metadata associated with each table. Two Excel workbooks are provided that separately contain all the data tables and reference tables. Finally, 52 csv files are provided that contain the information on each individual data and reference table, as well as a metadata file that serially lists information on all the fields for all the tables. 

This dataset contains information on cryostratigraphy and ground-ice content of the upper permafrost, which was based on the results of 22 field trips in 2018-2023. Field studies were performed in various regions of Alaska and Canadian Arctic including the following study areas: Utqiagvik (former Barrow), Teshekpuk Lake, Prudhoe Bay Oilfield, Toolik Lake, Jago River, Itkillik River, Anaktuvuk River, Fairbanks, Dalton Highway, Glennallen, Point Lay, Bylot Island (Canada), Inuvik-Tuktoyaktuk (Canada). Cryostratigraphy of the upper permafrost was studied mainly in coastal and riverbank exposures and frozen cores obtained from drilling with the SIPRE corer. Permafrost exposures and cores were described and photographed in the field, and obtained soil samples were delivered to the University of Alaska Fairbanks for additional descriptions and analyses. Ice contents of frozen soils (including gravimetric and volumetric moisture content, excess-ice content) were measured. The dataset includes cryostratigraphic descriptions, gravimetric (GMC) and volumetric (VMC) moisture content, excess-ice content (EIC), electrical conductivity (EC) and photographs of the permafrost exposures and frozen cores obtained from boreholes. 

Abstract In 2007, the Anaktuvuk River fire burned more than 1000 km²of arctic tundra in northern Alaska, ~ 50% of which occurred in an area with ice-rich syngenetic permafrost (Yedoma). By 2014, widespread degradation of ice wedges was apparent in the Yedoma region. In a 50 km²area, thaw subsidence was detected across 15% of the land area in repeat airborne LiDAR data acquired in 2009 and 2014. Updating observations with a 2021 airborne LiDAR dataset show that additional thaw subsidence was detected in < 1% of the study area, indicating stabilization of the thaw-affected permafrost terrain. Ground temperature measurements between 2010 and 2015 indicated that the number of near-surface soil thawing-degree-days at the burn site were 3 × greater than at an unburned control site, but by 2022 the number was reduced to 1.3 × greater. Mean annual ground temperature of the near-surface permafrost increased by 0.33 °C/yr in the burn site up to 7-years post-fire, but then cooled by 0.15 °C/yr in the subsequent eight years, while temperatures at the control site remained relatively stable. Permafrost cores collected from ice-wedge troughs (n = 41) and polygon centers (n = 8) revealed the presence of a thaw unconformity, that in most cases was overlain by a recovered permafrost layer that averaged 14.2 cm and 18.3 cm, respectively. Taken together, our observations highlight that the initial degradation of ice-rich permafrost following the Anaktuvuk River tundra fire has been followed by a period of thaw cessation, permafrost aggradation, and terrain stabilization. 

### Access Photos of ~50 permaforst boreholes and associated cores can be accessed and downloaded from the 'AR\_Fire\_Core_Photos' directory via: [https://arcticdata.io/data/10.18739/A2251FM9P/](https://arcticdata.io/data/10.18739/A2251FM9P/) ### Overview The Anaktuvuk River tundra fire burned more than 1,000 square kilometers of permafrost-affected arctic tundra in northern Alaska in 2007. The fire is the largest historical recorded tundra fire on the North Slope of Alaska. Fifty percent of the burn area is underlain by Yedoma permafrost that is characterized by extremely high ground-ice content of organic-rich, silty buried soils and the occurrence of large, syngenetic polygonal ice wedges. Given the high ground-ice content of this terrain, Yedoma is thought to be among the most vulnerable to fire-induced thermokarst in the Arctic. With this dataset, we update observations on near-surface permafrost in the Anaktuvuk River tundra fire burn area from 2009 to 2023 using repeat airborne LiDAR-derived elevation data, ground temperature measurements, and cryostratigraphic studies. We have provided all of the data that has gone into an analysis and resulting paper that has been submitted for peer review at the journal Scientific Reports. The datasets include: - 1 m spatial resolution airborne LiDAR-derived digital terrain models from the summers of 2009, 2014, and 2021. - The area in which thaw subsidence was detected in the multi-temporal LiDAR data using the Geomorphic Change Detection software. - A terrain unit map developed for the 50 square kilometer study area. - Ground temperature time series measurements for a logger located in the burned area and a logger located in an unburned area. The ground temperature data consist of daily mean measurements at a depth of 0.15 m (active layer) and 1.00 m (permafrost) from July 2009 to August 2023. - Photos ~50 permafrost boreholes and the associated cores collected there. - A borehole log and notes pdf also accompanies our studies on the cryostratigraphy of permafrost post-fire and our observations on the recovery of permafrost. 

Permafrost-agroecosystems include all cultivation and pastoral activities in areas underlain by permafrost. These systems support local livelihoods and food production and are rarely considered in global agricultural studies but may become more relevant as climate change is increasing opportunities for food production in high latitude and mountainous areas. The exact locations and amount of agricultural production in areas containing permafrost are currently unknown, therefore we provide an overview of countries where both permafrost and agricultural activities are present. We highlight the socioecological diversity and complexities of permafrost-agroecosystems through seven case studies: (1) crop cultivation in Alaska, USA; (2) Indigenous food systems and crop cultivation in the Northwest Territories, Canada; (3) horse and cattle husbandry and Indigenous hay production in the Sakha Republic, Russia; (4) mobile pastoralism and husbandry in Mongolia; (5) yak pastoralism in the Central Himalaya, Nepal; (6) berry picking and reindeer herding in northern Fennoscandia; and (7) reindeer herding in northwest Russia. We discuss regional knowledge gaps associated with permafrost and make recommendations to policy makers and land users for adapting to changing permafrost environments. A better understanding of permafrost-agroecosystems is needed to help sustainably manage and develop these systems considering rapidly changing climate, environments, economies, and industries. 

ABSTRACT The Yukon‐Kuskokwim Delta (YKD), covering ~75,000 km²of Alaska's discontinuous permafrost zone, has a historic (1902–2023) mean annual air temperature of ~−1°C and was previously thought to lack ice wedge networks. However, our recent investigations near Bethel, Alaska, revealed numerous near‐surface ice wedges. Using 20 cm resolution aerial orthoimagery from 2018, we identified ~50 linear km of ice wedge troughs in a 60 km²study area. Fieldwork in 2023 and 2024 confirmed ice wedges up to ~1.5 m wide and ~2.5 m in vertical extent, situated on average 0.9 m below the tundra surface (n = 29). Ground‐penetrating radar (GPR) detected additional ice wedges beyond those visible in the remote sensing imagery, suggesting an underestimation of their true abundance. Coring of polygonal centers revealed late‐Quaternary deposits, including thick early Holocene peat, late‐Pleistocene ice‐rich silts (reworked Yedoma), charcoal layers from tundra fires, and the Aniakchak CFE II tephra (~3600 cal yrs BP). Stable water isotopes from Bethel's wedge ice (mean δ¹⁸O = −15.7 ‰, δ²H = −113.1 ‰) indicate a relatively enriched signature compared to other Holocene ice wedges in Alaska, likely due to warmer temperatures and maritime influences. Expanding our mapping across the YKD using high‐resolution satellite imagery from 2012 to 2024, we estimate that the Holocene ice wedge zone encompasses ~30% of the YKD tundra region. Our findings demonstrate that ice wedge networks are more widespread across the YKD than previously recognized, emphasizing both the resilience and vulnerability of the region's warm, ice‐rich permafrost. These insights are crucial for understanding permafrost responses to climate change and assessing agricultural potential and development in the region.