Upwelling Channel with 4 Open Boundaries

[hpftcb]

Hi all,

I'D like to know if there is a way to set up an upwelling channel case with four open boundaries (on the contrary of Roms' upwelling test case) and zero inflow and outflow current.
I tried the following configuration, yet the wind generated current did not manage to radiate from the domain, it kept recirculating along the boundaries


LBC(isFsur) == Che Che Che Che ! free-surface
LBC(isUbar) == Shc Shc Shc Shc ! 2D U-momentum
LBC(isVbar) == Shc Shc Shc Shc ! 2D V-momentum
LBC(isUvel) == RadNud RadNud RadNud RadNud ! 3D U-momentum
LBC(isVvel) == RadNud RadNud RadNud RadNud ! 3D V-momentum
LBC(isMtke) == Gra Gra Gra Gra ! mixing TKE

LBC(isTvar) == RadNud RadNud RadNud RadNud ! temperature
RadNud RadNud RadNud RadNud ! salinity
RadNud RadNud RadNud RadNud ! dye_01

My domain is a 2.8 X 1.5 degree rectangle with 1.1 km resolution.

Regards,

Fernando T. C. Barreto

[kate]

What values are you using on the boundary? Is this a realistic domain or an idealized one? There's a reason the toy problems are all periodic channels or closed basins - except the Kelvin wave which looks awful if you run it longer than in its input file.

[hpftcb]

Hi, thanks for the reply

Yes,It's an idealized experiment (bathymetry is attached). It's a 3D case with 30 sigma layers (vt=2,vs=4), with salinity and temp field build from one WOA point (uniform horizontally), zero current velocity in all boundaries, and 5 m/s eastern wind input with ana_smflux.h. Boundaries conditions were build from initial condition file. Time step is 180.0d0.

[kate]

So your boundary conditions are level isopycnal surfaces. You blow a wind which is going to drive currents in balance with non-level isopycnals. If the boundary conditions aren't consistent with this, of course you'll get rim currents.

[wilkin]

If you are trying to set-up something that is effectively 1-dimensional in the vertical (you have no horizontal variation in density or wind forcing) then you might want a small double periodic domain. See the BIO_TOY and SED_TOY examples for guidance on how to do this.

[hpftcb]

Thank you for the replies.
I'll also try Gradient BC (Gradient = 0)

regards

[hpftcb]

I tried with grad = 0 in all boundaries and the domain energy kept rising (velocity rising) until my case blew up. Does anyone know if what I did is right, if I can't use grad to termohaline or something like that.

Thank you in advance


LBC(isFsur) == Gra Gra Gra Gra ! free-surface
LBC(isUbar) == Gra Gra Gra Gra ! 2D U-momentum
LBC(isVbar) == Gra Gra Gra Gra ! 2D V-momentum
LBC(isUvel) == Gra Gra Gra Gra ! 3D U-momentum
LBC(isVvel) == Gra Gra Gra Gra ! 3D V-momentum
LBC(isMtke) == Gra Gra Gra Gra ! mixing TKE

LBC(isTvar) == Gra Gra Gra Gra ! temperature
Gra Gra Gra Gra ! salinity
Gra Gra Gra Gra ! dye_01

! Adjoint-based algorithms can have different lateral boundary
! conditions keywords.

ad_LBC(isFsur) == Gra Gra Gra Gra ! free-surface
ad_LBC(isUbar) == Gra Gra Gra Gra ! 2D U-momentum
ad_LBC(isVbar) == Gra Gra Gra Gra ! 2D V-momentum
ad_LBC(isUvel) == Gra Gra Gra Gra ! 3D U-momentum
ad_LBC(isVvel) == Gra Gra Gra Gra ! 3D V-momentum
ad_LBC(isMtke) == Gra Gra Gra Gra ! mixing TKE

ad_LBC(isTvar) == Gra Gra Gra Gra ! temperature
Gra Gra Gra Gra ! salinity
Gra Gra Gra Gra ! dye_01