Changeset 3610 for trunk/LMDZ.COMMON/libf/evolution/recomp_tend_mod.F90

Timestamp:

Feb 5, 2025, 3:06:50 PM (9 hours ago)

Author:

jbclement

Message:

PEM:

• The sublimation flux can now be modified by the new function 'recomp_tend_h2o' to account for the growth of a dust lag layer (see Eran Vos's note for the formula).
• Addition of a function 'itp_tsoil' to compute the soil temperature at any point in the soil profile.

JBC

File:

• trunk/LMDZ.COMMON/libf/evolution/recomp_tend_mod.F90 (moved) (moved from trunk/LMDZ.COMMON/libf/evolution/recomp_tend_co2_mod.F90) (5 diffs)

trunk/LMDZ.COMMON/libf/evolution/recomp_tend_mod.F90

@@ -1 @@
-MODULE recomp_tend_co2_mod
+MODULE recomp_tend_mod
 
 implicit none
@@ -16 +16 @@
 !=======================================================================
 !
-!  To compute the evolution of the tendencie for co2 ice
+!  To compute the evolution of the tendency for co2 ice
 !
 !=======================================================================
@@ -61 +61 @@
 !=======================================================================
 
-SUBROUTINE recomp_tend_h2o(ngrid,nslope,timelen,d_h2oice,PCM_temp,PEM_temp)
+SUBROUTINE recomp_tend_h2o(icetable_depth_old,icetable_depth_new,tsurf,tsoil_PEM_timeseries_old,tsoil_PEM_timeseries_new,d_h2oice)
+
+use compute_soiltemp_mod, only: itp_tsoil
+use fast_subs_mars,       only: psv
 
 implicit none
@@ -67 +70 @@
 !=======================================================================
 !
-!  To compute the evolution of the tendencie for h2o ice
+!  To compute the evolution of the tendency for h2o ice
 !
 !=======================================================================
@@ -73 +76 @@
 ! Inputs
 ! ------
-integer,            intent(in) :: timelen, ngrid, nslope
-real, dimension(:), intent(in) :: PCM_temp, PEM_temp
+real,                 intent(in) :: icetable_depth_old, icetable_depth_new, tsurf
+real, dimension(:,:), intent(in) :: tsoil_PEM_timeseries_old, tsoil_PEM_timeseries_new
 ! Outputs
 ! -------
-real, dimension(ngrid,nslope), intent(inout) :: d_h2oice ! physical point field: Evolution of perennial ice over one year
+real, intent(inout) :: d_h2oice ! Evolution of perennial ice over one year
 
 ! Local:
 ! ------
+real            :: Rz_old, Rz_new, R_dec, hum_dec, psv_max_old, psv_max_new
+integer         :: t
+real, parameter :: coef_diff = 4.e-4 ! Diffusion coefficient
+real, parameter :: zcdv = 0.0325     ! Drag coefficient
 
-write(*,*) "Update of the H2O tendency due to lag layer"
+write(*,*) "> Updating the H2O tendency due to lag layer"
 
-! Flux correction due to lag layer
-!~ Rz_old = h2oice_depth_old*0.0325/4.e-4              ! resistance from PCM
-!~ Rz_new = h2oice_depth_new*0.0325/4.e-4              ! new resistance based on new depth
-!~ R_dec = (1./Rz_old)/(1./Rz_new)                     ! decrease because of resistance
-!~ soil_psv_old = psv(max(PCM_temp(h2oice_depth_old))) ! the maxmimum annual mean saturation vapor pressure at the temperature of the GCM run temperature at the old ice location
-!~ soil_psv_new = psv(max(PEM_temp(h2oice_depth_new))) ! the maxmimum annual mean saturation vapor pressure at the temperature of the PEM run temperature at the new ice location
-!~ hum_dec = soil_psv_old/soil_psv_new                 ! decrease because of lower water vapor pressure at the new depth
-!~ d_h2oice = d_h2oice*R_dec*hum_dec                   ! decrease of flux
+! Higher resistance due to growing lag layer (higher depth)
+Rz_old = icetable_depth_old*zcdv/coef_diff ! Old resistance from PCM
+Rz_new = icetable_depth_new*zcdv/coef_diff ! New resistance based on new depth
+R_dec = Rz_new/Rz_old ! Decrease because of resistance
+
+! The maxmimum of the daily averages over one year for the saturation vapor pressure at the ice table location
+psv_max_old = 0.
+psv_max_new = 0.
+do t = 1,size(tsoil_PEM_timeseries_old,2)
+    psv_max_old = max(psv_max_old,psv(itp_tsoil(tsoil_PEM_timeseries_old(:,t),tsurf,icetable_depth_old)))
+    psv_max_new = max(psv_max_new,psv(itp_tsoil(tsoil_PEM_timeseries_new(:,t),tsurf,icetable_depth_new)))
+enddo
+
+! Lower humidity due to growing lag layer (higher depth)
+hum_dec = psv_max_old/psv_max_new ! Decrease because of lower water vapor pressure at the new depth
+
+! Flux correction (decrease)
+d_h2oice = d_h2oice*R_dec*hum_dec
 
 END SUBROUTINE recomp_tend_h2o
 
-END MODULE recomp_tend_co2_mod
+END MODULE recomp_tend_mod