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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. 

As the Arctic warms and growing seasons start to lengthen, governments and producers are speculating about northern “climate-driven agricultural frontiers” as a potential solution to food insecurity. One of the central ecological factors in northern spaces, however, is permafrost (perennial frozen ground), which can drive cascading environmental changes upon thaw. Considering the land requirements for expanded agriculture and the unique challenges of northern farming, national and subnational governments are grappling with and facilitating this speculative boom in different ways. Analysing agricultural land use policy instruments from the US State of Alaska and the Republic of Sakha (Yakutia) in Russia, this paper investigates if and how permafrost factors into their legal frameworks and what impacts this has on agricultural development, conservation, and food security. Alaska and the Republic of Sakha were chosen for reasons including both having at least 100 years of agricultural history on permafrost soils, both containing extensive amounts of permafrost within their landmasses and both containing permafrost that is ice-rich. Comparing legal texts as indicative of state capacities and strategies to govern, the paper finds that the two regions diverge in how they understand and regulate permafrost, and suggests that these approaches could benefit from one another. Bringing together geoclimatic and sociocultural concerns to problematise static policy divisions, this paper gestures to a path forward wherein subnational policy can balance needs for food, environmental, and cultural security in the North. 

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. 

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. 

The Permafrost Grown project (NSF RISE Award # 2126965) is co-producing knowledge with farmers in Alaska (Tanana Valley and Bethel) to investigate the interactions and feedbacks between permafrost and agriculture. Additional project objectives include understanding legacy effects over a 120-year cultivation history in the Tanana Valley, evaluating the socio-economic effects of permafrost-agriculture interactions and provide decision making tools for farmers and finally to utilize education and outreach activities to share knowledge with the farmers and the public. The project focuses on in-the-ground farming in a range of cultivation types including crops, peonies and livestock. The project is funded through the National Science Foundation's (NSF) Navigating the New Arctic Initiative. Data was collected at a small (less than one acre) farm that grows diverse crops. This farm has been impacted by subsidence from thawing ice-rich permafrost. The goal of the celery trials was to compare celery grown in areas that are wetter due to subsidence and celery grown in an upper area that has been less impacted by subsidence. In addition, over the same period, monitoring was done of two compost piles: one older pile that has been actively used and maintained for a few years that will no longer be maintained (i.e. adding of new material for decomposition) and the establishment of a new compost pile. The monitoring of the compost pile is part of a larger effort to determine the thermal impact of commonly used agricultural practices and the potential impact on permafrost. 

The Permafrost Grown project (NSF RISE Award # 2126965) is co-producing knowledge with farmers in Alaska (Tanana Valley and Bethel) to investigate the interactions and feedbacks between permafrost and agriculture. Additional project objectives include understanding legacy effects over a 120-year cultivation history in the Tanana Valley, evaluating the socio-economic effects of permafrost-agriculture interactions and provide decision making tools for farmers and finally to utilize education and outreach activities to share knowledge with the farmers and the public. The project focuses on in-the-ground farming in a range of cultivation types including crops, peonies and livestock. The project is funded through the National Science Foundation's (NSF) Navigating the New Arctic Initiative. Temperature monitoring of various crop types with and without extension techniques was done at two farm sites in Fairbanks, Alaska (AK) during the 2022 growing season. This work was done through the Permafrost Grown Project as part of an effort to determine the thermal impact of commonly used agricultural seasonal-extension techniques, crop types and their potential impact on permafrost. Both farms are small scale, each cultivating on about 1 acre and both grow diverse crops. Both farms use various season extension techniques, including the use of plastic mulch to artificially warm soils and/or help control weeds. This dataset provides monitoring of ground temperatures at four depths (ground surface, 15 centimeter (cm), 50 cm and 100 cm) of various crops (carrots, cabbage, beets, onions, and squash). 

The University of Alaska Fairbanks T Field is a legacy farm field that is part of the National Science Foundation (NSF) Funded Permafrost Grown project. We are studying the long-term effects of permafrost thaw following initial clearing for cultivation purposes. In this regard, we have acquired very high resolution light detection and ranging (LiDAR) data and digital photography from a DJI M300 drone using a Zenmuse L1 and a MicaSense RedEdge-P camera. The Zenmuse L1 integrates a Livox Lidar module, a high-accuracy inertial measurement units (IMU), and a camera with a 1-inch CMOS on a 3-axis stabilized gimbal. The MicaSense RedEdge-P camera has five multispectral bands and a high-resolution panchromatic band. The drone was configured to fly in real-time kinematic (RTK) mode at an altitude of 60 meters above ground level using the DJI D-RTK 2 base station. Data was acquired using a 50% sidelap and a 70% frontlap for the Zenmuse L1 and an 80% sidelap and a 75% frontlap for the MicaSense. Additional ground control was established with a Leica GS18 global navigation satellite system (GNSS) and all data have been post-processed to World Geodetic System 1984 (WGS84) universal transverse mercator (UTM) Zone 6 North using ellipsoid heights. Data outputs include a two-class-classified LiDAR point cloud, digital surface model, digital terrain model, an orthophoto mosaic, and a multispectral orthoimage consisting of five bands. Image acquisition occurred on 18 August 2023. 

The Midnight Sun Golf Course in Fairbanks, Alaska is a legacy farm field that is part of the National Science Foundation (NSF) Funded Permafrost Grown project. This 65 hectare (ha) parcel was initially cleared for agriculture purposes but changed land-use practices to a golf course around 25 years ago. The land-use conversion was in part due to ice-rich permafrost thaw following clearing. We are studying the long-term effects of permafrost thaw following initial clearing for cultivation purposes. We are working with the current landowners to provide information regarding ongoing thermokarst development on the property and to conduct studies in reforested portions of the land area to understand land clearing and reforestation on permafrost-affected soils. In this regard, we have acquired very high resolution light detection and ranging (LiDAR) data and digital photography from a DJI M300 drone using a Zenmuse L1. The Zenmuse L1 integrates a Livox Lidar module, a high-accuracy inertial measurement units (IMU), and a camera with a 1-inch CMOS on a 3-axis stabilized gimbal. The drone was configured to fly in real-time kinematic (RTK) mode at an altitude of 60 meters above ground level using the DJI D-RTK 2 base station. Data was acquired using a 50% sidelap and a 70% frontlap. Additional ground control was established with a Leica GS18 global navigation satellite system (GNSS) and all data have been post-processed to World Geodetic System 1984 (WGS84) universal transverse mercator (UTM) Zone 6 North using ellipsoid heights. Data outputs include a two-class classified LiDAR point cloud, digital surface model, digital terrain model, and an orthophoto mosaic. Image acquisition occurred on 10 September 2023. The input images are available for download at http://arcticdata.io/data/10.18739/A2PC2TB1T.