Search for: All records

Abstract High-latitude and altitude cold regions are affected by climate warming and permafrost degradation. One of the major concerns associated with degrading permafrost is thaw subsidence (TS) due to melting of excess ground ice and associated thaw consolidation. Field observations, remote sensing, and numerical modeling are used to measure and estimate the extent and rates of TS across broad spatial and temporal scales. Our new data synthesis effort from diverse permafrost regions of North America and Eurasia, confirms widespread TS across the panarctic permafrost domain with rates of up to 2 cm yr⁻¹in the areas with low ice content and more than 3 cm yr⁻¹in regions with ice-rich permafrost. Areas with human activities or areas affected by wildfires exhibited higher subsidence rates. Our findings suggest that permafrost landscapes are undergoing geomorphic change that is impacting hydrology, ecosystems, and human infrastructure. The development of a systematic TS monitoring is urgently needed to deliver consistent and continuous exchange of data across different permafrost regions. Integration of coordinated field observations, remote sensing, and modeling of TS across a range of scales would contribute to better understanding of rapidly changing permafrost environments and resulting climate feedbacks. 

Abstract The 2015 spring flood of the Sagavanirktok River inundated large swaths of tundra as well as infrastructure near Prudhoe Bay, Alaska. Its lasting impact on permafrost, vegetation, and hydrology is unknown but compels attention in light of changing Arctic flood regimes. We combined InSAR and optical satellite observations to quantify subdecadal permafrost terrain changes and identify their controls. While the flood locally induced quasi‐instantaneous ice‐wedge melt, much larger areas were characterized by subtle, spatially variable post‐flood changes. Surface deformation from 2015 to 2019 estimated from ALOS‐2 and Sentinel‐1 InSAR varied substantially within and across terrain units, with greater subsidence on average in flooded locations. Subsidence exceeding 5 cm was locally observed in inundated ice‐rich units and also in inactive floodplains. Overall, subsidence increased with deposit age and thus ground ice content, but many flooded ice‐rich units remained stable, indicating variable drivers of deformation. On average, subsiding ice‐rich locations showed increases in observed greenness and wetness. Conversely, many ice‐poor floodplains greened without deforming. Ice wedge degradation in flooded locations with elevated subsidence was mostly of limited intensity, and the observed subsidence largely stopped within 2 years. Based on remote sensing and limited field observations, we propose that the disparate subdecadal changes were influenced by spatially variable drivers (e.g., sediment deposition, organic layer), controls (ground ice and its degree of protection), and feedback processes. Remote sensing helps quantify the heterogeneous interactions between permafrost, vegetation, and hydrology across permafrost‐affected fluvial landscapes. Interdisciplinary monitoring is needed to improve predictions of landscape dynamics and to constrain sediment, nutrient, and carbon budgets. 

This dataset contains orthomosaic images and digital surface models (DSMs) for an area of study near Old Man Camp in northern Alaska, USA (United States of America). The data were collected to further support ongoing research that aims to assess geomorphological and environmental changes near ground temperature monitoring sites, and to provide spatial data for validation of land surface deformation models. Flights from 2020 to 2022 were conducted using a DJI (Da-Jiang Innovations) Phantom 4 RTK (P4RTK) equipped with a DJI D-RTK 2 Mobile Base Station for real-time kinematic (RTK) positioning. For flight missions in 2023 through 2025, we utilized a DJI Matrice M300 RTK (M300RTK) drone equipped with a DJI Zenmuse P1 camera and a 35mm (millimeter) lens (45MP [megapixels]). An Emlid RS3 GNSS (Global Navigation Satellite System) base station was used for RTK positioning. All images were processed using Agisoft Metashape (v.2.2.0) following a standard three-dimensional mapping processing workflow utilizing ground control points measured in the field for horizontal and vertical corrections and reliable reproduction from year to year. All DSM and orthomosaic files are projected using NAD83 (North American Datum of 1983) State Plane 4 and ellipsoidal heights in meters. The Old Man site is located approximately 310 miles (499km [kilometer]) south of Deadhorse on a wide subarctic valley floor. Landcover units include Graminoid-moss tundra and graminoid, prostrate-dwarf-shrub, moss tundra (wet and moist nonacidic). 

This dataset contains orthomosaic images and digital surface models (DSMs) for an area of study near Imnavait in northern Alaska, United States of America (USA). The data were collected to further support ongoing research that aims to assess geomorphological and environmental changes near ground temperature monitoring sites, and to provide spatial data for validation of land surface deformation models. The 2022 flight was conducted using a DJI Phantom 4 RTK (P4RTK) equipped with a DJI D-RTK 2 Mobile Base Station for real-time kinematic (RTK) positioning. For flight missions in 2023 and beyond, we utilized a DJI Matrice M300 RTK (M300RTK) drone equipped with a DJI Zenmuse P1 camera and a 35mm lens (45MP). An Emlid RS3 GNSS base station was used for RTK positioning. All images were processed using Agisoft Metashape (v.2.2.0) following a standard three-dimensional mapping processing workflow utilizing ground control points measured in the field for horizontal and vertical corrections and reliable reproduction from year to year. All DSM and orthomosaic files are projected using NAD83 State Plane 4 and ellipsoidal heights in meters. The Imnavait site is located approximately 125 miles (201 kilometers (km)) south of Deadhorse in the foothills of the Brooks Range in northern Alaska. Landcover units include Graminoid-moss tundra and graminoid, prostrate-dwarf-shrub, moss tundra (wet and moist nonacidic). 

This dataset contains orthomosaic images and digital surface models (DSMs) for an area of study near Chandalar Shelf in northern Alaska, USA (United States of America). The data were collected to further support ongoing research that aims to assess geomorphological and environmental changes near ground temperature monitoring sites, and to provide spatial data for validation of land surface deformation models. Drone flights from 2020 to 2022 were conducted using a DJI (Da-Jiang Innovations) Phantom 4 RTK (P4RTK) equipped with a DJI D-RTK 2 Mobile Base Station for real-time kinematic (RTK) positioning. Flights in 2023 were not conducted due to poor weather conditions. For flight missions in 2024 and beyond, we utilized a DJI Matrice M300 RTK (M300RTK) drone equipped with a DJI Zenmuse P1 camera and a 35mm (millimeter) lens (45MP (megapixels)). An Emlid RS3 GNSS (Global Navigation Satellite System) base station was used for RTK positioning. All images were processed using Agisoft Metashape (v.2.2.0) following a standard three-dimensional mapping processing workflow utilizing ground control points measured in the field for horizontal and vertical corrections and reliable reproduction from year to year. All DSM and orthomosaic files are projected using NAD83 (North American Datum of 1983) State Plane 4 and ellipsoidal heights in meters. The Galbraith Lake site is situated in a broad glaciated mountain valley located approximately 140 miles (225km [kilometers]) south of Deadhorse along the Dalton Highway in northern Alaska. Landcover units include Graminoid-moss tundra and graminoid, prostrate-dwarf-shrub, moss tundra (wet and moist nonacidic). 

This dataset contains orthomosaic images and digital surface models (DSMs) for an area of study near Chandalar Shelf in northern Alaska, USA (United States of America). The data were collected to further support ongoing research that aims to assess geomorphological and environmental changes near ground temperature monitoring sites, and to provide spatial data for validation of land surface deformation models. Drone flights from 2020 to 2022 were conducted using a DJI Phantom 4 RTK (P4RTK) equipped with a DJI D-RTK 2 Mobile Base Station for real-time kinematic (RTK) positioning. Flights in 2023 were not conducted due to poor weather conditions. For flight missions in 2024 and beyond, we utilized a DJI Matrice M300 RTK (M300RTK) drone equipped with a DJI Zenmuse P1 camera and a 35mm (millimeter) lens (45MP (megapixels)). An Emlid RS3 GNSS (Global Navigation Satellite System) base station was used for RTK positioning. All images were processed using Agisoft Metashape (v.2.2.0) following a standard three-dimensional mapping processing workflow utilizing ground control points measured in the field for horizontal and vertical corrections and reliable reproduction from year to year. All DSM and orthomosaic files are projected using NAD83 State Plane 4 and ellipsoidal heights in meters. The Chandalar Shelf site is located at milepost 238 on the Dalton Highway in northern Alaska approximately 60 miles (97km (kilometers)) north of Coldfoot in a broad glaciated mountain valley. Landcover units include Graminoid-moss tundra and graminoid, prostrate-dwarf-shrub, moss tundra (wet and moist nonacidic). 

This dataset contains orthomosaic images and digital surface models (DSMs) for an area of study near Happy Valley in northern Alaska, USA (United States of America). The data were collected to further support ongoing research that aims to assess geomorphological and environmental changes near ground temperature monitoring sites, and to provide spatial data for validation of land surface deformation models. The 2020 and 2022 flights were conducted using a DJI (Da-Jiang Innovations) Phantom 4 RTK (P4RTK) equipped with a DJI D-RTK 2 Mobile Base Station for real-time kinematic (RTK) positioning. For flight missions in 2023 and 2024, we utilized a DJI Matrice M300 RTK (M300RTK) drone equipped with a DJI Zenmuse P1 camera and a 35mm lens (45MP). An Emlid RS3 GNSS (Global Navigation Satellite System) base station was used for RTK positioning. All images were processed using Agisoft Metashape (v.2.2.0) following a standard three-dimensional mapping processing workflow utilizing ground control points measured in the field for horizontal and vertical corrections and reliable reproduction from year to year. All DSM and orthomosaic files are projected using NAD83 (North American Datum of 1983) State Plane 4 and ellipsoidal heights in meters. The two Happy Valley sites are located on the unglaciated foothills of the Brooks Range in northern Alaska, approximately 82 miles (132km [kilometers]) south of Deadhorse along the Dalton Highway. Landcover units include tussock-graminoid, dwarf- shrub tundra and low-shrub tundra (moist acidic). 

This dataset contains orthomosaic images and digital surface models (DSMs) for an area of study near Deadhorse in northern Alaska, USA (United States of America). The data were collected to further support ongoing research that aims to assess geomorphological and environmental changes near ground temperature monitoring sites, and to provide spatial data for validation of land surface deformation models. The 2022 flight was conducted using a DJI (Da-Jiang Innovations) Phantom 4 RTK (P4RTK) equipped with a DJI D-RTK 2 Mobile Base Station for real-time kinematic (RTK) positioning. For flight missions in 2023 and beyond, we utilized a DJI Matrice M300 RTK (M300RTK) drone equipped with a DJI Zenmuse P1 camera and a 35mm (millimeter) lens (45MP). An Emlid RS3 GNSS (Global Navigation Satellite System) base station was used for RTK positioning. All images were processed using Agisoft Metashape (v.2.2.0) following a standard three-dimensional mapping processing workflow utilizing ground control points measured in the field for horizontal and vertical corrections and reliable reproduction from year to year. All DSM and orthomosaic files are projected using NAD83 (North American Datum of 1983) State Plane 4 and ellipsoidal heights in meters. The Deadhorse site is located approximately 5 miles (8km [kilometer]) south of the community of Deadhorse, Alaska on the inner coastal plain with river terraces along the Sagavanirktok River. Landcover units include Graminoid-moss tundra and graminoid, prostrate-dwarf-shrub, moss tundra (wet and moist nonacidic). 

This dataset contains orthomosaic images and digital surface models (DSMs) for an area of study near Franklin Bluffs in northern Alaska, USA (United States of America). The data were collected to further support ongoing research that aims to assess geomorphological and environmental changes near ground temperature monitoring sites, and to provide spatial data for validation of land surface deformation models. Flights from 2020 to 2022 were conducted using a DJI (Da-Jiang Innovations) Phantom 4 RTK (P4RTK) equipped with a DJI D-RTK 2 Mobile Base Station for real-time kinematic (RTK) positioning. For flight missions in 2023 and beyond, we utilized a DJI Matrice M300 RTK (M300RTK) drone equipped with a DJI Zenmuse P1 camera and a 35mm (millimeter) lens (45MP [megapixels]). An Emlid RS3 GNSS (Global Navigation Satellite System) base station was used for RTK positioning. All images were processed using Agisoft Metashape (v.2.2.0) following a standard three-dimensional mapping processing workflow utilizing ground control points measured in the field for horizontal and vertical corrections and reliable reproduction from year to year. All DSM and orthomosaic files are projected using NAD83 State Plane 4 and ellipsoidal heights in meters. The Franklin Bluffs site is located approximately 42 miles (67km [kilometers]) south of Deadhorse on the inner coastal plain with river terraces along the Sagavanirktok River. Landcover units include Graminoid-moss tundra and graminoid, prostrate-dwarf-shrub, moss tundra (wet and moist nonacidic).