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Oceanic transport toward the Arctic Ocean consists mostly of Atlantic Water (AW hereafter) being transported by the Norwegian Atlantic Current toward higher latitudes (Helland-Hansen & Nansen, 1909). At the entrance of the Barents Sea, the AW flow divides in two branches. One branch enters the Barents Sea where it can either be transformed into dense water and exits at depths as so-called Arctic Intermediate Water (Schauer et al., 1997), or melt ice and become part of the "estuarine" component of the Arctic Ocean (Eldevik & Nilsen, 2013;Rudels, 2016;Stigebrandt, 1981). The other AW branch forms the West Spitsbergen Current which further splits into two branches. One of these recirculates and heads South, and merges with the East Greenland Current, and the other enters the Arctic through Fram Strait. The latter branch can either melt ice, or subduct below the lighter colder and fresher layer of Arctic Water. This latter branch then follows a pathway along the continental slope North of Svalbard and Franz Josef Land toward the eastern Nansen Basin, slowly losing its properties (Bluhm et al., 2020;Timmermans & Marshall, 2020).

Fjords along the western Antarctic Peninsula are episodically exposed to strong winds flowing down marine-terminating glaciers and out over the ocean. These wind events could potentially be an important mechanism for the ventilation of fjord waters. A strong wind event was observed in Andvord Bay in December 2015, and was associated with significant increases in upper-ocean salinity. We examine the dynamical impacts of such wind events during the ice-free summer season using a numerical model. Passive tracers are used to identify water mass pathways and quantify exchange with the outer ocean. Upwelling and outflow in the model fjord generate an average salinity increase of 0.3 in the upper ocean during the event, similar to observations from Andvord Bay. Down-fjord wind events are a highly efficient mechanism for flushing out the upper fjord waters, but have little net impact on deep waters in the inner fjord. As such, summer episodic wind events likely have a large effect on fjord phytoplankton dynamics and export of glacially modified upper waters, but are an unlikely mechanism for the replenishment of deep basin waters and oceanic heat transport toward inner-fjord glaciers.

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