Spatial and temporal variability of taiga snow properties during melting period in Sodankylä, Finland

Abstract. This study investigates the temporal and spatial variability of physical snow properties during the melting period in taiga snowpack conditions in Sodankylä, northern Finland. Weekly snow pit measurements – including stratigraphy, temperature, and density – were conducted at four locations over an eight-week period from March to May in 2023 to assess landscape-scale variability. At three sites, the average spatial variability of automatically measured snow height over time was 7.4 cm (9.7 %). Density measurements using the snow water equivalent tube showed higher spatial variability compared to those made with a density cutter, and this variability increased during melt. Differences between measurement techniques exceeded differences between locations. Peaks in density profiles were mainly linked to melt-freeze crusts and ice layers. Depth hoar was consistently found in lower snowpack layers before melting, reaching a maximum relative height of 21.5 %. The appearance of melt-freeze crusts following short-term temperature shifts highlights the snowpack's sensitivity to daily thermal cycles. Initial wetness was observed mid-snowpack, suggesting that refreezing from cold nights operates top-down, not affecting the full depth. Moist and wet layers became more prevalent in the upper snowpack, while the wettest layers accumulated at the base rather than being evenly distributed.