| Summary: | The processes of meltwater storage in firn and the impact of refreezing on firn-coveredglaciers have been investigated on the Greenland ice-sheet. On Svalbard, climate changepromotes the disappearance of firn on glaciers. This thesis project aims to monitor theheat exchanges between the snowpack and the ice surface on a non firn-covered glacier,on Foxfonna, Spitzbergen, Svalbard, and to draw the picture of the events occurring inthe snowpack over a melting season, from May to July 2021.This report has two aims. First, to highlight the evolution of snow properties; bulk den-sity, heat flow,Snow Water Equivalent(SWE, amount of water that would result from themelting of 1m2surface area of that snowpack), and albedo, during melting, and attemptsto do so during the formation of superimposed ice, e.g. refreezing of meltwater on theglacier ice. Second, to model the snow melt using local weather data and to compare themodelled results with the observed melt, measured periodically throughout the fieldworkperiod. Snow pits were dug to measure the snow temperature and density, and to observethe evolution of the snowpack properties. In the snow pits, the focus was set on the snowmetamorphism, albedo, water content and stakes measurements. Finally, stakes measure-ments were realized to assess the growth of superimposed ice.The weather data indicates a sudden warming on the 2ndof June, which rendered thesnowpack isothermal (0°C over the entire column), as observed from the snow temper-ature. The already established melt became stronger as a result of this warm event, asobserved in the snow depth data. The snow melt modelled from the 6thto the 11thofJune indicates results diverging from the actual snow melt by 95%. Nonetheless, themodel describes the main physics of the system, as it predicts that melting must occur, asexpected. The divergence between the modelled and the observed melt can be attributedto the use of weather stations located away from the site. As snow melted, the bulkdensity increased, resulting in a stronger ...
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