3D numerical model for Pearl River estuary

A 3D numerical model with an orthogonal curvilinear coordinate in the horiz ontal direction and sigma coordinate in the vertical direction has been dev eloped. This model is based on POM (Princeton Ocean Model). In this model a second moment turbulence closure submodel is embedded and the stratificati on caused by salinity and temperature is considered. Furthermore, to adapt to estuary locations where the flow pattern is complex, the horizontal time differencing is implicit with the use of a time-splitting method instead o f the explicit method in POM. This model is applied to the Pearl River estu ary, which is the largest river system in South China, with Hong Kong at th e eastern side of its entrance. The computation is verified and calibrated with field measurement data. The computed results mimic the field data well .