Interannual variability of the arctic snowpack: Results from long-term observations at Ny-Ålesund, Svalbard

The Arctic is undergoing rapid environmental changes, with profound implications for snowpack dynamics, hydrology, and regional climate feedbacks. Ny-Ålesund, Svalbard (79°N), serves as an important site for documenting these changes due to its unique geographic location in the Arctic and its year-round research infrastructure. Here, we present the results of a comprehensive snowpack monitoring at Ny-Ålesund during five consecutive winter seasons (2018–2023).

Manual in-situ measurements of snow stratigraphy—including layer thickness, density, temperature, and hardness—were performed in weekly snow pits. While the region is traditionally considered as dominated by cold, shallow, and wind-affected "tundra” snow, recent winters exhibit increasing occurrences of snow characteristics not attributed to tundra snow, such as melt-freeze layers, internal ice accumulation, or wet snow. These anomalies are linked to rising temperatures, increased precipitation, and episodic winter rainfall events, which contrast sharply with the historical tundra snow regime. While the winter of 2019–2020 displayed classic tundra snow conditions, others winter seasons showed dominant maritime snow features. The statistical analysis of the observed physical snow parameters reveals a high variability of the snowpack characteristics. Such variability underscores the sensitivity of Arctic snowpack to local changes and highlights the challenges in predicting seasonal snowpack evolution. Simulating this enhanced variability will likely require snow models with enhanced capabilities.

This research emphasizes the importance of long-term, high-resolution observations in the remote Arctic. As the Arctic continues to warm, understanding these dynamics is essential for assessing broader environmental impacts, from permafrost degradation to shifts in regional water and biogeochemical cycles. The results call for sustained monitoring efforts and adaptive research strategies to address the evolving challenges posed by climate change in the Arctic.