Add a check that figures out the value of fv where the wind threshold…

… won't be met and dust will be zero

src/biogeochem/test/DustEmis_test/test_DustEmis.pf

@@ -19,7 +19,6 @@ module test_DustEmis
   use WaterType, only : water_type
   use FrictionVelocityMod, only : frictionvel_type
   use unittestWaterTypeFactory, only : unittest_water_type_factory_type
-  use abortutils, only : endrun
 
   implicit none
 
@@ -267,7 +266,6 @@ contains
                                      / this%frictionvel_inst%fv_patch(p)
        call this%dust_emis%WritePatchToLog( p )
     end do
-    call endrun( "exit early")
   end subroutine print_values
 
   !-----------------------------------------------------------------------
@@ -327,16 +325,43 @@ contains
 
   end subroutine check_dust_emis
 
+    !-----------------------------------------------------------------------
+
+  @Test
+  subroutine dust_zero_for_fixed_ratio(this)
+    ! Check dust emissions are zero for a no wind
+    class(TestDustEmis), intent(inout) :: this
+    integer :: p
+    real(r8) :: flx_mss_vrt_dst_tot
+    real(r8) :: fv
+    real(r8) :: SaltationFactor
+
+    call this%create_atm2lnd()
+    call this%dust_emis%GetConstVars( SaltationFactor )
+    ! Figure out what fv needs to be so that the wind threshold will be u10*(1/(1-eps))
+    fv = ( SaltationFactor / sqrt( this%atm2lnd_inst%forc_rho_downscaled_col(bounds%begc)) ) - 1.d-15
+    call this%create_fv( fv=fv )
+    call this%dust_emis%DustEmission(bounds, this%num_nolakep, this%filter_nolakep, this%atm2lnd_inst, &
+                      this%soilstate_inst, this%canopystate_inst, this%water_inst%waterstatebulk_inst, &
+                      this%water_inst%waterdiagnosticbulk_inst, this%frictionvel_inst)
+    call this%dust_emis%DustDryDep(bounds, this%atm2lnd_inst, this%frictionvel_inst)
+    call this%print_values()
+    do p = bounds%begp, bounds%endp
+       call this%validate_patch(p)
+       call this%dust_emis%GetPatchVars( p, flx_mss_vrt_dst_tot=flx_mss_vrt_dst_tot )
+       @assertEqual( flx_mss_vrt_dst_tot, 0.0_r8 )
+    end do
+
+   end subroutine dust_zero_for_fixed_ratio
+
+  !-----------------------------------------------------------------------
+
   @Test
   subroutine check_dust_emis_increasing_wind(this)
     ! Check dust emissions with increasing wind
     class(TestDustEmis), intent(inout) :: this
     integer :: p, c
     real(r8) :: flx_mss_vrt_dst_tot
-    real(r8) :: vlc_trb_1
-    real(r8) :: vlc_trb_2
-    real(r8) :: vlc_trb_3
-    real(r8) :: vlc_trb_4
     real(r8) :: fv = 4.0_r8
     real(r8) :: u10 = 10._r8
     real(r8) :: total_dust0, total_dust_higher