Open AccessCalculating Estuarine Exchange Flow Using Isohaline Coordinates*
Author(s) -
Parker MacCready
Publication year - 2011
Publication title -
journal of physical oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.706
H-Index - 143
eISSN - 1520-0485
pISSN - 0022-3670
DOI - 10.1175/2011jpo4517.1
Subject(s) - estuary , flux (metallurgy) , residence time (fluid dynamics) , eulerian path , flow (mathematics) , salinity , knudsen number , discontinuity (linguistics) , mechanics , geology , environmental science , oceanography , physics , mathematics , mathematical analysis , geotechnical engineering , chemistry , organic chemistry , lagrangian
A method for calculating subtidal estuarine exchange flow using an isohaline framework is described, and the results are compared with those of the more commonly used Eulerian method of salt flux decomposition. Concepts are explored using a realistic numerical simulation of the Columbia River estuary. The isohaline method is found to be advantageous because it intrinsically highlights the salinity classes in which subtidal volume flux occurs. The resulting expressions give rise to an exact formulation of the time-dependent Knudsen relation and may be used in calculation of the saltwater residence time. The volume flux of the landward transport, which can be calculated precisely using the isohaline framework, is of particular importance for problems in which the saltwater residence time is critical.