Problem Statement
Large river plume (like Columbia's) is a major coastal feature in many parts of the world. The buoyant
freshwater carries nutrients, sediments etc. into coastal ocean and therefore plays an important part
in the coastal ecological system. Physically this is essentially a surface-dominated process.
Previous studies (e.g., Garcia-Berdeal et al. 2002) are restricted to systems with mild bottom slope or
with mild stratifications. Here we present results from ELCIRC and SELFE of a large river plume, and thus it's
a very challenging problem, especially for terrain-following models. We welcome any results and comparison from
those models.
Benchmark set-up
Domain: The domain is the Columbia River estuary and associated plume region. As a first step,
we study the natural tendancy of the plume by turning off all external forcing (tides and wind), and only apply
a steady freshwater discharge of 7000 m^3/s (long-term average of Columbia River).
Domain discretization:
We use 43 Z-levels in the ELCIRC run, and 54 SZ-levels in the SELFE run.Time:
The two models were run for a total of 14 days.
ELCIRC runInput files
Results
Surface plume at t=14 days. (a) SELFE with ELM transport; (b) ELCIRC; (c) SELFE with upwind transport.
Note: the results shown here were obtained with a slightly different version of the code, but
you should be able to see qualitatively similar results from your own runs.
I. Garcia-Berdeal, B. M. Hickey, and M. Kawase, "Influence of wind stress and ambient flow on a high discharge river plume.," J. Geophys. Res., vol. 107, pp. 3130, 2002.
Zhang, Y.-L. and Baptista, A.M. (submitted) "A semi-implicit Eulerian-Lagrangian finite-element model for cross-scale ocean circulation, with hybrid vertical coordinates",
Int. J. Num. Fluids.