New ROMS configuration for Southern California Bight

Descendant of the previous UCLA configurations(cf., Marchesiello et al. 2003; Dong at al., 2009)

Improved from the previous SCB 1-km modeling

- higher resolutions(L1: 20 km → 5 km, L2: 6 km → 1 km, L3: 1 km → 250 m,...)

- use of UCLA ROMS (were IRD-ROMS-AGRIF)better hydrodynamic kernel, robust KPP, better MPI scaling,...

- more frequent boundary update (was 30 days → 2 hours)

- inclusion of surface gravity waves

- utility of WRF (was MM5) and SWAN

Newest quadrupleNested ROMS configuration

L1 (5 km)

L2 (1 km)L2 (1 km)

L3 (250 m)

L3 (250 m) L4 (75 m) L4 (75 m)

L3 (250 m) runs(Aug. - Nov., 2006)

USWL3 250 m, z = 0 m

USWL3 250 m, z = -100 m

USWL3 250 m, z = -500 m

Effects of surface waves(subtidal EKE)

w/o wave

w/ wave

difference

Conservative Wave Effects: Overall Thermocline Deepening and Altering Upper Mean Circulation

with WEC (with WEC) – (no WEC)

mean mixed-layer depth(KPP hbl)

mean stream function(upper layer > -25 m)

x 103 (m2/s)

(m)

with WEC (with WEC) – (no WEC)

~15 %

~15 %

Vortex force vs. Stokes-Coriolis effect

- mean advection of eddies (JSC : Stokes-Coriolis force)- eddy-wave interaction (JVF : vortex force) --> exceeds JSC

~ <JVF>/<JSC>Ro=

L4 (75 m) runs(Aug. - Nov., 2006)

HTP 1-/5-mile outfalls

mean depth-integrated passive tracer concentration

mean tracer concentration along HTP transect

mean velocity along HTP transect

Mean mixed layer depth(from KPP)

Hovmoller plotsof depth-averagedtracer concentration

Alongshore profiles of depth-averaged tracer concentration at the shoreline

Time series of depth-averaged tracer concentration at the shoreline at selected locations.

Single-point PDF of depth-averaged passive tracer concentrations at the shore

PSD of depth-averaged passive tracer concentrations at the shoreline

SSS

Hovmoller plotsof shoreline SSS

Mean surface normalized relative vorticity and TKE (all frequencies)

bandpass-filtered surface kinetic energy

high frq. (< 8h) semi-diurnal diurnal sub-tidal (> 36h)

L5 (20 m) test run(7 days in Nov., 2006)