A two-dimensional numerical model of estuarine circulation: The effects of altering depth and river discharge

Open Water Processes of the San Francisco Estuary: From Physical Forcing to Biological Responses

“…If longitudinal dispersion did not depend on compression of the salinity and density field, an exponent of -1 would result. In a uniform estuary in which gravitational circulation moved salt up-estuary, X2 would respond to flow with an exponent of -1/3 (Festa and Hansen 1976). The exponent determined by Monismith et al 2002 was much smaller, apparently because of landward salt flux due to gravitational circulation in deeper parts of the estuary.…”

“…Although gravitational circulation may be possible in unstratified conditions, it generally occurs in the presence of stratification (Hansen and Rattray 1966;Festa and Hansen 1976;Geyer 1993;Monismith et al 1996;Cheng and Casulli 1996). Gravitational circulation is an important mechanism for upstream salt penetration, thereby providing a negative feedback that limits the seaward movement of the salt field (Hansen and Rattray 1966;Monismith et al 2002, see "Movement of the Salt Field", p. 27).…”

Long-term trends in the distribution of phytoplankton in Chesapeake Bay: roles of light, nutrients and streamflow

“…For example, predictable blooms of diatoms are known to 'Also: Horn Point Environmental Laboratories. Center for Environmental and Estuarine Studies, University of Maryland, Box 775, Cambridge, Maryland 21613, USA accompany the spring freshet in several important estuaries in the United States, including San Francisco Bay (Peterson et al 1975, Festa & Hansen 1976, 1978, Conomos & Peterson 1977, Cloern & Cheng 1981, Cloern et al 1983), Delaware Bay (Sharp et al 1982, Pennock 1985, Pennock & Sharp 1986, and the Hudson River estuary (Malone 1977, Malone & Chervin 1979, Malone et al 1980.…”

Mechanisms and variability of salt transport in partially-stratified estuaries

“…Early studies assumed that the salt transport and the salt balance are in equilibrium with the freshwater flow and the tides (Knudsen 1900;Hansen and Rattray 1965;Hansen and Rattray 1966), producing an equilibrium distribution of salt along the estuary (Festa and Hansen 1976;Chatwin 1976). Festa and Hansen (1976) used a two-dimensional numerical model to ilustrate the variability of the length of the salinity intrusion over a range of depths, vertical mixing coeffcients, and freshwater flows.…”