The circulation of Prince William Sound, Alaska, is described using hydrographic (1974--1989), current meter (1977--1979), and acoustic Doppler current profiler (1986--1990) observations from both the sound and the adjacent Gulf of Alaska. Ancillary data include data for winds, freshwater runoff, and satellite-tracked drifters. Prince William Sound is a small inland sea in that it is wide enough to have appreciable horizontal cyclonic circulation. It is also a fjord in that it has basin depths to 700 m but is stilled at 180 m to the open ocean. The general circulation pattern is defined by a portion of the westward flowing Alaska Coastal Current on the Gulf of Alaska shelf that enters Prince William Sound through Hinchinbrook Entrance and transists the sound from east to west before exiting through Montague Strait and rejoining the coastal current. However, there is much variability in this circulation, especially in the transport through Hinchinbrook Entrace.

In addition, some of the water entering the sound becomes involved in the cyclonic circulation in the northern sound and so has a longer residence time. The circulation is strongly mediated by seasonal and interannual variations in winds and freshwater runoff as well as by local topography both inside and outside the sound. In winter, the strong cyclonic winds over the Gulf of Alaska cause costal downwelling and strong flow in the upper layers into Prince William Sound through Hinchinbrook Entrace and out through Montague Strait. In summer, the downwelling ceases, allowing subsurface denser water to rise above the sill and flow into the sound through the bottom layers of Hinchinbrook Entrance. We conclude that the best transport data came from Montague Strait, from which we estimate that ~40% of the volume of Prince William Sound is flushed in summer (May--September). This estimated volume rises to about 200% in winter (October--April). ¿ American Geophysical Union 1994