Seasonal variability of near‐surface hydrography and frontal features in the northern Gulf of Alaska and Prince William Sound

Abstract

The meridional structure and seasonal cycles of near‐surface hydrography and frontal features in the northern Gulf of Alaska and Prince William Sound are described from high‐resolution measurements of near‐surface temperature and salinity acquired by a vessel‐mounted thermosalinograph. Near‐surface temperature exhibits a well‐defined seasonal cycle with little variation between basin and shelf waters. Near‐surface salinity exhibits a well‐defined seasonal cycle that is confined largely to the shelf waters reflecting the influence of coastal freshwater inputs. Prominent near‐surface fronts at the shelf break, at the entrance to Prince William Sound, and in northern Prince William Sound intensify and weaken following the seasonal cycles of freshwater discharges into the northern Gulf of Alaska. These respective fronts are maintained by freshwater from the Alaska Coastal Current, the Copper River, and the snowfields and glaciers of northern Prince William Sound.