Mechanisms and variability of salt transport in partially-stratified estuaries
Bowen, Melissa M.
MetadataShow full item record
The variability of salt transport determines the variation of the length of the salinity intrusion and the large-scale density gradient in an estuary. This thesis contains three studies that address salt transport and the salt balance. The variation of salt transport with the depth, the along-channel salinity gradient, and the amplitude of the tidal velocity is investigated with analytic and numerical models. The results indicate that salt transport increases dramatically during stratified periods when vertical mixing is weak. Analysis of salt transport from observations in the Hudson Estuary show that stratified periods with elevated estuarine salt transport occur in five-day intervals once a month during apogean neap tides. Oscillatory salt transport, which is hypothesized to be primarily caused by lateral exchange and mixing of salt, appears to play a more minor role in the salt balance of the estuary. The salt balance of the estuary adjusts very little to the spring-neap modulation of salt transport but adjusts rapidly to pulses of freshwater flow. A simple model is used to investigate the process and time scales of adjustment of the salt balance by connecting variations of salt transport to the variations of freshwater flow and vertical mixing. The results show the length of the salinity intrusion adjust via advection to rapid and large increases in freshwater flow. The salinity intrusion adjusts more rapidly to the spring-neap cycle of tidal mixing the higher the freshwater flow.
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2000
Suggested CitationThesis: Bowen, Melissa M., "Mechanisms and variability of salt transport in partially-stratified estuaries", 2000-02, DOI:10.1575/1912/2130, https://hdl.handle.net/1912/2130
Showing items related by title, author, creator and subject.
Sands and environmental conditions impact the abundance and persistence of the fecal indicator bacteria Enterococcus at recreational beaches Halliday, Elizabeth (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2012-09)The marine fecal indicator Enterococcus is measured at beaches to detect fecal contamination events, and beaches are closed to bathers when Enterococcus is found to exceed the federally mandated limit. This dissertation ...
Benthuysen, Jessica A. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2010-06)In a stratified rotating fluid, frictionally driven circulations couple with the buoyancy field over sloping topography. Analytical and numerical methods are used to quantify the impact of this coupling on the vertical ...
Functional characterization and expression of molluscan detoxification enzymes and transporters involved in dietary allelochemical resistance Whalen, Kristen E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2008-06)Understanding how organisms deal with potentially toxic or fitness-reducing allelochemicals is important for understanding patterns of predation and herbivory in the marine environment. The ability of marine consumers ...