Our recently developed models have included the Columbia River fresh water discharge, which is simulated in a realistic set-up (including high-frequency winds, atmospheric heat flux, and tides).
The 2-km resolution model (see the model domain) is extended 41-50N along the Oregon and Washington coasts. It has been run for a period of Aug 2008 - Dec 2010. The animations below show surface currents (vectors) and temperature (color) every 1 h for three different periods in an area near the estuary. White contours are salinity (28, 30, and 32 psu, shown as thick, thinner, and very thin lines). Half-tone contours are bathymetry (50, 100, and 200 m).
In winter (predominantly downwelling regime) the river plume turns predominantly to the north. It is colder than the surrounding ocean water. The river front is moved closer to the shore during strong wind-driven downwelling events (associated with northward winds).
2km movie #1 (avi)
2km movie #2 (avi)
In summer, upwelling favorable (southward) winds can turn the river plume to the south. The river water is warmer than the surrounding ocean (upwelled) water. Intensive mixing of the river and upwelled ocean waters occur in the estuary and over the inner shelf, within the 50 m isobath (at a glance, during upwelling events, more river-ocean mixed (colder) water is found to the south of the river mouth - dynamical reasons for that are being clarified):
2km movie #3 (avi)
The 1-km resolution model domain is extended 41-47N in the alongshore direction (see model domain..) The solution is available for a period of Jan-Jun 2011. Movies below show how much more fine-scale structure is revealed by the improved resolution. Year 2011 had anomalously large river volume discharge in spring. At the same time, upwelling in May-June was relatively week.
1km movie #1 (avi)
1km movie #2 (avi)
1km movie #3 (avi)