about atmospheric forcing

[mengqingjun]

I have a question that if I don't active BULK_FLUXS in .h file, as arango wrote in viewtopic.php?f=30&t=3003&hilit=boundary+conditions that

ROMS just needs shflux, swflux, swrad (with some CPP options), sustr, and svstr.

.I want to apply the surface forcing without BULK_FLUXS.Only a dalily shflux,swflux,swrad,sustr,svstr from ECMWF.
Then what cpp definations should I active in the .h file ? Like SOLAR_SOURCE, LONGWAVE or LONGWAVE_OUT,EMINUSP,DIURNAL_SRFLUX...I am really confused about these cpp definations about surface forcing. Could anyone kindly help me ? Thank you !

[kate]

You can help yourself by using "grep" to see which files contain these strings:
* SOLAR_SOURCE turns up in pre_step3d.F where it is used to heat the water column.
* EMINUSP and the LONGWAVE options turn up in bulk_flux.F.
* DIURNAL_SRFLUX is in set_data.F, where it is applied to the shortwave radiation (if you have SHORTWAVE).

[mengqingjun]

Thank you kate for your replies ! I turn off the BULK_FLUXS, and as arango said, ROMS needs shflux, swflux, swrad (with some CPP options), sustr, and svstr as the atmospheric forcing. I am wondering we have already had shflux, then what swrad is used for ?

[kate]

If the water is clear, not all incoming light will enter as a surface boundary heating. It will instead penetrate down some distance and be absorbed as heat there. See above for SOLAR_SOURCE.

[derek_grimes]

I'm not sure this is the appropriate place to ask a follow-up question, but here it goes...

When not using bulk_fluxes, or solar_source, why do we need to provide swflux? Is that not a component of shflux?

Thanks,
D

[kate]

There are times when you'd need shortwave radiation flux anyway. Looking at get_data.F, you need srflx when SHORTWAVE is defined. SHORTWAVE is defined in these circumstances:

Code: Select all

#if defined LMD_SKPP     || defined SOLAR_SOURCE   || \
    defined BULK_FLUXES  || defined BIOLOGY
# define SHORTWAVE
#endif

(from globaldefs.h).