Accurate calculation of horizontal diffusive transport is important in modeling temperature, salinity, sediment, and pollutant transport in estuaries and the coastal ocean. Many three-dimensional estuarine and coastal ocean models employ a so-called sigma coordinate transformation because of its useful applications with irregular bathymetry. However, for steep bottom slopes, the conventional definition of horizontal diffusion causes spurious diffusive transport. In this paper, a new formula is presented and tested for salinity diffusion in a quiescent-sloping basin under no external forces. Results indicate that this formula produces almost no spurious diffusion, so that the initial salinity field remains unchanged after a 30-d simulation.
[1]
Robert L. Haney,et al.
On the Pressure Gradient Force over Steep Topography in Sigma Coordinate Ocean Models
,
1991
.
[2]
N. A. Phillips,et al.
A COORDINATE SYSTEM HAVING SOME SPECIAL ADVANTAGES FOR NUMERICAL FORECASTING
,
1957
.
[3]
Alan F. Blumberg,et al.
Modeling vertical and horizontal diffusivities with the sigma coordinate system
,
1985
.
[4]
Y. Peter Sheng,et al.
On Modeling Three-Dimensional Estuarine and Marine Hydrodynamics
,
1987
.
[5]
M. Danard,et al.
A modified sigma equations' approach to the numerical modeling of Great Lakes hydrodynamics
,
1972
.