PRESENTATION
Chunyan Li, Harry Roberts, Eddie Weeks, Greg Stone, and Zhixuan Feng cli@lsu.edu
Coastal Studies Institute, Department of Oceanography and Coastal Sciences, School of the Coast and Environment, Louisiana State University, Baton Rouge, LA 70803
Abstract
Atchafalaya River discharges 30% of the freshwater from the Mississippi River which results in an almost entirely fresh Atchafalaya Bay in spring. A one‐month deployment of two tripods equipped with multiple equipments was made in the central Atchafalaya Bay between the Atchafalaya River mouth and the mouth of the Wax Lake for the study of the hydrodynamics and suspended sediments. Data from these deployments were collected between March 20 and April 19, 2006. The first tripod was about 3 and 2 km to the Atchafalaya River delta and the Wax Lake delta, respectively. The second tripod was about 2 km from the Wax Lake delta and 6 km southwest of the first tripod. The instruments include Seabird SBE plus conductivity and temperature sensor with dissolved oxygen, acoustic Doppler profilers, five additional temperature sensors deployed at different depths, and OBS. Data from a nearby WAVCIS station are also examined in combination with data from the two tripods. It is found that two episodes of what appeared to be events of saltwater intrusion occurred during the 1‐month deployment. These events appear to be associated with an increase of salinity of about 2 PSU and a decrease of dissolved oxygen, a fact which, we hypothesize, is caused by the increased stability of the water column when a bottom density current is developed. By examining the tide stage, it is apparent that these saltwater intrusion events occurred after a high water slack and lasted for 0.5 to 2 hours, respectively.
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