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1. Beaver Pond Locations in Arctic Alaska, 1949 to 2020.

   https://doi.org/10.18739/A26T0GX5M  

   Tape, Ken; Clark, Jason; Jones, Benjamin (January 2021, NSF Arctic Data Center)

   Beavers were not previously recognized as an Arctic species, and their engineering in the tundra is considered negligible. Recent findings suggest that beavers have moved into arctic tundra regions and are controlling surface water dynamics, which strongly influence permafrost and landscape stability. These data show beaver pond locations in the Alaska Arctic identified in aerial photography and satellite imagery. Black and white aerial photography is from 1949-55, color infrared aerial photography (AHAP) is from 1976-84, and high-resolution satellite imagery is from 2000-2020. The number of beaver ponds doubled in most areas of ~2003 and ~2017 images. Earlier stages of beaver engineering are evident in ~1980 imagery, and there is no evidence of beaver engineering in ~1952 imagery, consistent with observations from Indigenous communities describing the influx of beavers over the period. 

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2. Expanding beaver pond distribution in Arctic Alaska, 1949 to 2019

   https://doi.org/10.1038/s41598-022-09330-6  

   Tape, Ken D.; Clark, Jason A.; Jones, Benjamin M.; Kantner, Seth; Gaglioti, Benjamin V.; Grosse, Guido; Nitze, Ingmar (December 2022, Scientific Reports)

   Abstract Beavers were not previously recognized as an Arctic species, and their engineering in the tundra is considered negligible. Recent findings suggest that beavers have moved into Arctic tundra regions and are controlling surface water dynamics, which strongly influence permafrost and landscape stability. Here we use 70 years of satellite images and aerial photography to show the scale and magnitude of northwestward beaver expansion in Alaska, indicated by the construction of over 10,000 beaver ponds in the Arctic tundra. The number of beaver ponds doubled in most areas between ~ 2003 and ~ 2017. Earlier stages of beaver engineering are evident in ~ 1980 imagery, and there is no evidence of beaver engineering in ~ 1952 imagery, consistent with observations from Indigenous communities describing the influx of beavers over the period. Rapidly expanding beaver engineering has created a tundra disturbance regime that appears to be thawing permafrost and exacerbating the effects of climate change. 

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3. Predicted expansion of beaver pond distribution in Arctic Alaska, 1910–2090

   https://doi.org/10.1088/1748-9326/adeba2  

   Tape, Ken D; Speed, James_D M (June 2025, Environmental Research Letters)

   Abstract Ecosystem engineering by beavers is a nascent disturbance in the Arctic tundra, appearing in the 1970s in western Alaska and since expanding deeper into tundra regions. Evidence from modeling and observations indicates that beaver ponds act as biophysical oases, and we anticipate myriad changes as these disturbances are constructed along tundra streams, sloughs, and lake outlets. We used over 11 000 mapped beaver pond locations in Arctic Alaska and their climatic, geographic, and environmental attributes to understand (1) which of those attributes control the distribution of beaver ponds, and, if temperature is a factor, (2) how beaver pond distribution will change under future climate scenarios. Of the variables used in the ensemble modeling approach, mean annual temperature was the most important variable in determining beaver pond locations, with pond occurrences more likely in warmer locales (>−2 °C). The distance to water was also important in determining beaver pond locations, as expected, with higher likelihood of ponds closer to water features. Lowland topographic variables were also relevant in determining the distribution of beaver ponds. Under the current climate, beaver ponds are widespread in most of western Alaska, matching the predicted extent of potential occupancy, with the exception of areas furthest from treeline, implying possible dispersal lags or other factors. By 2050, under future climate scenarios (RCP8.5; 2090 for RCP6.0), the entire North Slope of Alaska, which currently has no beaver ponds, is predicted to be suitable for beaver ponds, comparable to western Alaska in 2016. The vast extent of future beaver engineering in tundra regions will require reenvisioning the typical tundra stream ecosystems of northern Alaska, northern Canada, northern Europe, and northern Asia to include more extensive wetlands, routine disturbances, permafrost thaw, and other features of these nascent oases that are not fully understood. 

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4. Classifier-guided diffusion model for seasonal arctic melt pond data generation

   https://doi.org/10.1117/12.3056017  

   Liu, Ruixu; Sultana, Aqsa; Aspiras, Theus H; Asari, Vijayan K; Sudakow, Ivan; Cooper, Lee W (May 2025, SPIE)

   Alam, Mohammad S; Asari, Vijayan K (Ed.)
5. Melt pond UNet for the segmentation of the Arctic area, Aug-Sept 2005

   https://doi.org/10.18739/A20G3H067  

   Sultana, Aqsa; Asari, Vijayan; Sudakow, Ivan; Liu, Ruixu; Demchev, Denis (January 2022, NSF Arctic Data Center)

   The dataset contains aerial photographs of Arctic sea ice obtained during the Healy-Oden Trans Arctic Expedition (HOTRAX) captured from a helicopter between 5 August and 30 September, 2005. A total of 1013 images were captured, but only 100 images were labeled. The subset of 100 images was created exclusively for the purpose of segmenting sea ice, meltponds, and open water. Original images, labels, and code for segmentation are included in the above files. For dataset, refer site: Ivan Sudakow, Vijayan Asari, Ruixu Liu, & Denis Demchev. (2022). Melt pond from aerial photographs of the Healy–Oden Trans Arctic Expedition (HOTRAX) (1.0) [Data set]. Zenodo. https://doi.org/10.5281/zenodo.6602409 Manuscript: I. Sudakow, V. K. Asari, R. Liu and D. Demchev, "MeltPondNet: A Swin Transformer U-Net for Detection of Melt Ponds on Arctic Sea Ice," in IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, vol. 15, pp. 8776-8784, 2022, doi: 10.1109/JSTARS.2022.3213192. 

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