time-dependent bottom fluxes in roms?

[falk]

hi all,
in the past we've done simulations where we specified constant bottom tracer fluxes in roms via specifying ana_btflux.h.
This works great.

However, now we want to have time-dependent bottom tracer flux (and fresh water flux) that represents the source of an ocean outfall. These fluxes would be in a netcdf file. Is there a way to specify a time-dependent bottom tracer and freshwater flux?

thank you
falk

[jcwarner]

how about using Wilkin's new LwSrc? This is a vertical point source at a rho point and can have tracers with it.
(as opposed to LuvSrc which is a lateral point source at a u- or v- point).

You need to set the correct flags (now in the ocean.in) but it could be a viable option. The LwSrc is in get_data, looking for a netcdf file:

#ifndef ANA_PSOURCE
!
!-----------------------------------------------------------------------
! Point Sources/Sinks time dependent data.
!-----------------------------------------------------------------------
!
! Point Source/Sink vertically integrated mass transport.
!
IF (LuvSrc(ng).or.LwSrc(ng)) THEN
CALL get_ngfld (ng, iNLM, idRtra, SSF(ng)%ncid, &
& 1, SSF(ng), update(1), &
& 1, Nsrc(ng), 1, 2, 1, Nsrc(ng), 1, &
& SOURCES(ng) % QbarG)
....
! Tracer Sources/Sinks.
DO i=1,NT(ng)
IF (LtracerSrc(i,ng)) THEN
CALL get_ngfld (ng, iNLM, idRtrc(i), SSF(ng)%ncid, &
& 1, SSF(ng), update(1), &
& 1, Nsrc(ng), N(ng), 2, 1, Nsrc(ng), N(ng), &
& SOURCES(ng) % TsrcG(:,:,:,i))
...

[falk]

john, thank u. this looks like what we need. we will check it out. -falk

[wilkin]

ana_btflux.h sets the bottom boundary condition to the vertical turbulent flux of tracer, like a heat flux. It has no associated volume flux of water, so it is not the same thing as using LwSrc which adds water of a given tracer concentration.

It's like the difference between warming the ocean by blowing warm air over it, versus warming the ocean by adding hot water to it.

Depending on what problem you are trying to tackle you'll need to make the appropriate choice.

I see code for loading bottom tracers fluxes from netcdf in get_data.F ...

Code: Select all

#  ifndef ANA_BPFLUX
!
!-----------------------------------------------------------------------
!  Passive tracers bottom fluxes.
!-----------------------------------------------------------------------
!
      DO i=NAT+1,NT(ng)
        CALL get_2dfld (ng, iNLM, idTbot(i), ncFRCid(idTbot(i),ng),     &
     &                  nFfiles(ng), FRC(1,ng), update(1),              &
     &                  LBi, UBi, LBj, UBj, 2, 1,                       &
...

and in set_data.F ...

Code: Select all

#  if defined BIOLOGY || defined SEDIMENT || defined T_PASSIVE
!
!-----------------------------------------------------------------------
!  Set kinematic surface and bottom pasive tracer fluxes (T m/s).
!-----------------------------------------------------------------------
!

so it looks to me like what you are asking for already exists.