CORIE - Modeling ELCIRC/SELFE Benchmarks: Juan de Fuca eddy

Acknowledgments We obtained information on the domain and initial S,T information etc from Mike Foreman, who with others have recently completed a study with ROMS. Therefore this test serves as an interesting inter-model comparison. Problem Statement The presence of a cyclonic eddy outside the mouth of Strait of Juan de Fuca under summer condition has long been recognized (Tully 1942; Denman and Freeland 1985; Weaver and Hsieh 1987). The domain is shown in Fig. 1 below.

Benchmark set-up Domain: The domain includes Strait of Juan de Fuca, Vancouver Island and Washington coast. Domain discretization: We use 26 S layers in the SELFE run, and variable grid size with highest resolution (~2.5km) near Juan de Fuca and canyons outside the mouth.Time: The model was run for a total of 60 days, with a time step of 120s.Parameters: The most important parameter for this test is the Kriging option near Cape Flattery. We didn't use Kriging for the entire domain to improve efficiency.Changes to the source code: The changes in the source code elfe1_5k2.f90 are confined to reading spatially varying but temporally uniform wind from wind_[uv].hgrid. The modified code is given below.

SELFE run Input files

source code modified source code
param.in Input parameters
hgrid.gr3 Horizontal grid
vgrid.in Vertical grid
adv.gr3 ELM tracking option flags;
diffmax.gr3 max. diffusivity
diffmin.gr3 background diffusivity
drag.gr3 bottom drag coefficients
interpol.gr3 interpolation mode input
krvel.gr3 Kriging flags
s_nudge.gr3 nudging factors for salinity
t_nudge.gr3 nudging factors for temperature
wind_u.hgrid wind speed in east-west direction
wind_v.hgrid wind speed in south-north direction
hotstart.in initial conditions for S,T interpolated from summer climatology from Mike Foreman
flux.th "discharge" at JdF boundary calculated from a 3D barotropic SELFE model

Results
Residual salinity and velocity at 35m (averaged from day 45 to 60). The corresponding ROMS results can be found in Foreman et al. (submitted).

Discussion

References

Foreman, M.G.G., Wiggins, W., MaxFayden, A., Hickey, B.M., Thomson, R.E. and Di Lorenzo, E. (submitted) Modeling the genration of the Juan de Fuca Eddy. J. Geo. Res.