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ReadMe of ROMS model output.
Identifier : SHF3+TRC
composed by: dgrimes@ucsd.edu 
date       : 03/2020
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Introduction
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Background:
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Cross-shore exchange of passive tracers is important in coastal oceanography. There are myriad processes that can drive exchange across- the shallow inner-shelf (depth <15m). Two mechanisms are evaluated in this study:

Diurnal Thermally Driven Exchange: considered a dominant mechanism for driving cross-shore exchange, particularly for weak winds, is driven by baroclinic pressure gradient set-up by a depth dependent thermal response to surface heat flux (SHF) forcing. 

Transient Rip-current (TRC) Driven Exchange: a relatively novel mechanism, discovered by Kumar & Feddersen (2017, JPO I-II & GRL), is also driven by baroclinic pressure gradient but is set-up by cross-shore inhomogeneous mixing induced by TRCs on the stratified inner-shelf.

Methods: 
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A series of simulations are conducted with SHF and TRC forcing (separately and combined). 
Four passive tracer releases are used to evaluate exchange induced by each forcing case. 

Model:
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48h simulations are performed using the Coupled Ocean Atmosphere Wave and Sediment Transport (COAWST) modeling system, coupling the ROMS circulation model with the SWAN wave model. 
TRCs are generated by adding surf-zone barotropic-rotational body forcing via one-way coupling with wave-resolving model funwaveC.

Links:
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COAWST: https://www.usgs.gov/software/coupled-ocean-atmosphere-wave-sediment-transport-coawst-modeling-system

ROMS: https://www.myroms.org/wiki/Documentation_Portal

SWAN: http://swanmodel.sourceforge.net/

funwaceC: http://falk.ucsd.edu/funwaveC.html

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Component Specifics
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Forcing:
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For this simulation, denoted SHF3+TRC, combined SHF and wave/TRC forcing are applied. The purpose of which, is to evaluate the combined effect of thermal forcing and TRC induced mixing on shoreline released tracer evolution. At model initialization, t=0, the solar time of day is mid-day, ts=12 h. An ensemble of 4 SHF+TRC forced simulations, varying the solar time at initialization (ts={0,6,12,18 h}), are used to account for transient effects due to initalization time / initial conditions.  
  

Files:
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There are 24 netcdf4 output files in this component named:
ocean_his_%05d.nc
where     %05d   file number represents time. 

Each file consists of snap-shots at 15 min intervals for ~2 hours.


Short-list of included variables...
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sea-surface   (zeta)
3D velocity   (u,v,w)
3D Stokes vel (u_stokes,...)
2D vel        (ubar,vbar)
2D Stokes vel (ubar_stokes,...)
Temperature   (temp)
Tracer        (dye_01, dye_02, ...)
Density       (rho)
Vertical diffusivity (Akt, Akv)
GLS turbulence closure vars (tke, gls_*)