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The shelfbreak current over the Beaufort Sea continental slope is known to be one of the most energetic features of the Beaufort Sea hydrography. In January 2005, three oceanographic moorings deployed over the Canadian (eastern) Beaufort Sea continental slope simultaneously recorded two consecutive shelfbreak current events with along‐slope eastward bottom‐intensified flow up to 120 cm s−1. Both events were generated by the local wind forcing associated with two Pacific‐born cyclones passing north of the Beaufort Sea continental slope toward the Canadian Archipelago. Over the mooring array, the associated westerly wind exceeded 15 m s−1. These two cyclones generated storm surges along the Beaufort Sea coast with sea surface height (SSH) rising up to 1.4 m following the two westerly wind maxima. We suggest that the westerly along‐slope wind generated a surface Ekman onshore transport. The associated SSH increase over the shelf produced a cross‐slope pressure gradient that drove an along‐slope eastward geostrophic current, in the same direction as the wind. This wind‐driven barotropic flow was superimposed on the background baroclinic bottom‐intensified shelfbreak current that consequently amplified. Summer‐fall satellite altimetry data for 1992–2013 show that the SSH gradient in the southeastern Beaufort Sea is enhanced over the upper continental slope in response to frequent storm surge events. Because the local wind forcing and/or sea‐ice drift could not explain the reduction of sea‐ice concentration over the Beaufort Sea continental slope in January 2005, we speculate that wind‐driven sea level fluctuations may impact the sea‐ice cover in winter. Downwelling‐favorable winter storms result in storm surges along the Beaufort Sea coastCross‐slope pressure gradient drives barotropic flow enhancing baroclinic along‐slope currentDownwelling of the Pacific Winter and Atlantic Water was observed

Typically, all undecomposed metazoans found in formalin‐poisoned cups of sediment traps are considered to be active intruders (or “swimmers”) and are removed to prevent an overestimation of the downward particle flux. However, intact metazoans dead before entering the trap should be included in the estimation of downward flux of carbon. Arctic copepods collected in the field were killed either by formalin to mimic death by actively swimming into the formalin‐poisoned cups, or by crowding or high temperature and then preserved in formalin to simulate death before entering the trap. In the crowding and heat treatments, 64% of Calanus hyperboreusand C. glacialisand 44% of Pareuchaeta glacialisdiffered from copepods killed by formalin in the postmortem posture of the antennules or swimming legs. These frequencies were used to estimate the contribution of passively sinking copepods (PSCs) to the particulate organic carbon (POC) flux measured by a sediment trap moored at 70 m in the Beaufort Sea (Canadian sector of the Arctic Ocean). PSCs represented only a small fraction (<5%) of the copepods collected in the trap, thus justifying the removal of swimmers from samples to avoid a massive overestimation of fluxes. Nevertheless, PSCs contributed 36% of the overall POC flux of 6.8 g C m‐2yr‐1, and discarding them along with the swimmers would have resulted in a significant underestimation of downward export. Given their rich carbon content (up to 50%), PSCs could be an important food resource for pelagic and benthic scavengers.