doubt regarding unit conversion of evaporation

[tara]

Dear all,

I want to understand what is the correct way to convert the MERRA latent heat flux conversion into evaporation flux(E=H/Lv). finally to calculate evaporation(kg/m^2/sec)-precipitation(kg/m^2/sec)=swflux(cm/day)


With Regards-
Tara

[wilkin]

It's in the code in bulk_flux.F.

Code: Select all

!  For EMINUSP option,  EVAP = LHeat (W/m2) / Hlv (J/kg) = kg/m2/s
!                       PREC = rain = kg/m2/s
!
!  To convert these rates to m/s divide by freshwater density, rhow.
! ...
# ifdef EMINUSP
          evap(i,j)=LHeat(i,j)/Hlv(i,j)

Divide latent flux in W/m2 by the latent heat of vaporization Hlv ~= 2.501e6 J/kg.

ROMS sets a spatially varying Hlv early in the bulk_flux.F subroutine making a small adjustment for the actual SST:

Code: Select all

!
!  Compute latent heat of vaporization (J/kg) at sea surface, Hlv.
!
          Hlv(i,j)=(2.501_r8-0.00237_r8*TseaC(i))*1.0E+6_r8
!

[tara]

Thank you very much Wilkin .