Physical Oceanography of the Bahia Blanca Estuary

Abstract

The Bahía Blanca Estuary is the flooded remnant of the northern portion of the Late Pleistocene-Early Holocene Colorado Delta. As a result of the distributary system developed during its formation, the geomorphologic characteristics are rather complex. Consequently, the dynamic processes acting upon it are still more complex and significantly challenging to establish it within the parameters that frequently study other estuaries in the world. The temperature distribution is quite homogeneous in the estuary. Based on the salinity distribution, the estuary can be divided into two sectors: an inner one showing partially mixed characteristics with a strong tendency to become sectionally homogeneous during runoff standard, and an outer sector which is sectionally homogeneous. Salinity values in the inner sector may be larger than those observed in the inner continental shelf. Although the tide is the dominant process, the wind in a semiarid region plays a significant role in the dynamics of the estuary—mainly because it actively affects the time and the height of the tide and, concomitantly, the resulting tidal currents. From the geomorphologic side, the tides and tidal currents are modified by the presence of the flats. However, they can also produce by themselves changes in the duration of the flood and ebb periods as well as the intensity and direction of the currents. Although there are over 50 years of studies of the various oceanographic components of the estuary, mostly concentrated along the Canal Principal with the hope that the results represent what happens along all the estuary. However, judging from the geomorphology alone, the differences are remarkable. Furthermore, estuarine areas farther south of the Canal Principal have pristine conditions which are not by far what happens in the Canal Principal.