10 Sep 2025

Snow Depth Measurements from Arctic Tundra and Boreal Forest Collected During NASA SnowEx Alaska Campaign

Abstract: Boreal forest and Arctic tundra environments collectively hold the largest percentage of global terrestrial seasonal snow cover. Тhe in-situ snow measurement network is sparse and costly in these remote northern regions. Here, we complement existing snow depth monitoring in Arctic tundra and boreal forest by presenting an extensive (64°N–70°N) snow depth dataset and description of ground-based snow depth measurements collected during the NASA SnowEx Alaska intensive field campaign, March 7–16, 2023. We also report the accuracy of snow depth measurements in shallow boreal forest and Arctic tundra snowpack and share considerations in developing the consistent and repeatable snow depth data collection procedures. Snow depth measurements and technical validation described in this paper can serve as a robust product for testing snow remote sensing techniques, and for providing a reference dataset for climatological and hydrological studies.

2 Jun 2025

Future Coastal Tundra Loss due to Compounding Environmental Changes in Alaska

Abstract: Anthropogenic climate change is amplified in the Arctic, where less sea ice enables energetic wave climates while higher air and soil temperatures increase tundra erodibility. These changes are likely to exacerbate retreat of coastal tundra yet remain poorly constrained on timescales relevant to storm wave impacts. A stochastic weather generator is used to create 1,000 synthetic hourly time series of waves, water levels, offshore sea ice concentration, and air temperatures used as forcing for an efficient coastal tundra model. The ensemble set of morphological change simulations provides a probabilistic perspective on the range of tundra retreats and the relative effects of each environmental forcing. Ensembles show as the depth of the erodible layer increases, the style of tundra retreat shifts from a consistent recession to intermittent events with large magnitudes and a factor 2 range in outcomes. Model scenarios highlight shallower thaw depths narrows the range of retreats and reduces individual extreme events, but a dynamic feedback between beach slopes, wave runup, and thermally limited erosion volumes ultimately increases the number of storm events associated with retreat. The minimum tundra retreat is governed by background shoreline change and the specifics of the topographic profile dominate underlying changes in the future wave climate statistics and open water season. As the Arctic continues to warm, the change in retreat style will have significant ramifications for coastal resilience.