Eddy-Like Features Near St. Matthew Island, Eastern Bering Sea Shelf: Observations From the Oculus Coastal Glider Geophysical Research Letters

The eastern Bering Sea Shelf is characterized by high biological productivity, seasonal sea ice, and commercially important fisheries. Enhanced productivity is often associated with small-scale oceanographic features. Our objective was to use an autonomous underwater vehicle to examine features typically missed by ~20-km spaced shipboard sampling. A coastal glider (Oculus) sampled ~3 dives hr−1 with horizontal spacing of ~300 m per dive in August/September 2017. In the north-south transition zone near St. Matthew Island, the glider sampled four eddy-like features associated with weaker vertical stratification. These features had diameters of 15–20 km and were associated with higher surface chlorophyll. Shipboard data collected in the same region approximately a month later showed that a similar feature was associated with high concentrations of small copepods. Incorporating higher resolution sampling available with gliders into the Bering Sea observing network will improve our understanding of ecosystem response to patchiness in the system. Grant no. NA15OAR4320063