| Summary: | No region has felt the effects of global climate change more acutely than the cryosphere, which has changed at an unprecedented rate in the past two decades. The scientific consensus is that these changes are driven largely by increasing ocean heat content at high latitudes. In southeast Greenland, acceleration and retreat of the marine-terminating glaciers contributes significantly towards global sea level rise. Circulation in the fjords which accommodate these glaciers is thought to be driven both by freshwater input and by barrier wind-driven shelf exchange. Due to a scarcity of data, particularly from winter, the balance between these two mechanisms is not fully understood. In Svalbard, increasing water temperature has decimated sea ice cover in many of the fjords, and had substantial implications for the local ecosystem. While there is a relatively comprehensive literature on shelf exchange mechanisms in Svalbard fjords, questions remain over how the internal circulation interacts with exchange mechanisms. The region shares a similar underwater topography and oceanographic setting with southeast Greenland, with marine-terminating glaciers in close proximity to warm Atlantic waters, and results from Svalbard can hence be used to inform studies of high-latitude fjord-shelf exchange in a broader context. A realistic numerical model was constructed with the aim of better understanding the interaction between Kangerdlugssuaq Fjord and the adjacent continental shelf, and quantifying heat exchange during winter. The model was initially run in an idealised configuration with winter climatological forcing fields, incorporating a parameterisation for melting at the terminus, and used to test the impact of barrier wind events. The Earth's rotation played a crucial role in the nature of the circulation and exchange in the fjord, with inflow on the right (looking up-fjord) and outflow on the left. While the heat delivered into the fjord-mouth was smaller than that observed in summer, the background internal circulation ...
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