Salt conservation

[mathieu]

When sea water evaporates from the surface of the ocean some denser waters are formed on the surface, which then goes deeper.

This physical phenomena is modelled in ROMS by a salt flux, that is an increase in salt concentration at the surface of the model with the same free surface. The relevant code is triggered by the options BULK_FLUXES and EMINUSP:

Code: Select all

stflx(i,j,isalt)=cff*(evap(i,j)-rain(i,j))

The obvious problem is that salt is not conserved. That is one take a sea like the Adriatic, closed the Ottranto strait, stop river inflow and precipitation, then the quantity of salt in the model domain keep increasing while the water level stay the same.
This problem is probably well known. The program SELFE is using the same salt flux but SHYFEM is using the correct water flux.
What would be the difficulty of modifying the model so that the correct fluxes are taken into account? Is it a real problem for long term runs?

[kate]

You might try contacting Paul Budgell, who was just messing with in the Caspian Sea.