Steve Pond

Observations and numerical modeling of the circulation, dynamics and mixing in British Columbia coastal waters.

Direct current observations have been made since about 1980, as well as observations of the property fields from which the gross circulation and dynamics of coastal waters were inferred previously. However, the horizontal, vertical and long period variations of the currents and the coupling among wind, runoff, tidal forcing and possible instability and mixing mechanisms need further study.

The observations have been used to study the long period variations of the currents in the Strait of Georgia, deep water replacement and tidal currents in Indian Arm, the tidal, wind driven and estuarine currents in Knight Inlet and the circulation in the Sechelt Inlet system. In the Sechelt Inlet experiment, phytoplankton samples, oxygen levels, nutrients and primary productivity were also observed. These data along with the results from moored sediment traps should allow estimates of source and sink terms in the oxygen budget.

Numerical models of the currents and density field evolution for inlets, using a Mellor-Yamada second order closure for the vertical mixing, have been developed. Tests of them using our observational database from Knight Inlet and the Burrard Inlet-Indian Arm system show that the main features of the circulation and density distribution can be simulated.