force releaseheights for bkwd depo runs

src/get_wetscav.f90

@@ -20,7 +20,7 @@
 !**********************************************************************
 
 subroutine get_wetscav(itime,ltsample,loutnext,jpart,ks,grfraction,inc_count,blc_count,wetscav)
-!                          i      i        i     i     o           o
+!                          i      i        i     i   i    o           o          o       o
 !*****************************************************************************
 !                                                                            *
 ! Calculation of wet deposition using the concept of scavenging coefficients.*
@@ -138,6 +138,8 @@ subroutine get_wetscav(itime,ltsample,loutnext,jpart,ks,grfraction,inc_count,blc
            memtime(1),memtime(2),interp_time,lsp,convp,cc)
     endif
 
+!  If total precipitation is less than 0.01 mm/h - no scavenging occurs
+    if ((lsp.lt.0.01).and.(convp.lt.0.01)) goto 20
 
 ! get the level were the actual particle is in
     do il=2,nz

src/readcommand.f90

@@ -329,11 +329,15 @@ subroutine readcommand
      case (3)  ! 3 .. wet deposition in outputfield 
         ind_rel = 3
          write(*,*) ' #### FLEXPART WET DEPOSITION BACKWARD MODE    #### '
+         write(*,*) ' #### Releaseheight is forced to 0 - 20km      #### '
+         write(*,*) ' #### Release is performed above ground lev    #### '
          WETBKDEP=.true.
          allocate(xscav_frac1(maxpart,maxspec))
      case (4)  ! 4 .. dry deposition in outputfield
          ind_rel = 4
          write(*,*) ' #### FLEXPART DRY DEPOSITION BACKWARD MODE    #### '
+         write(*,*) ' #### Releaseheight is forced to 0 - 2*href    #### '
+         write(*,*) ' #### Release is performed above ground lev    #### '
          DRYBKDEP=.true.
          allocate(xscav_frac1(maxpart,maxspec))
      end select

src/readreleases.f90

@@ -515,6 +515,20 @@ subroutine readreleases
     stop
   endif
 
+  ! If FLEXPART is run for backward deposition force zpoint
+  !*********************************************************************
+  if (WETBKDEP) then
+      zpoint1(numpoint)=0.
+      zpoint2(numpoint)=20000.
+      kindz(numpoint)=1
+  endif
+  if (DRYBKDEP) then
+      zpoint1(numpoint)=0.
+      zpoint2(numpoint)=2.*href
+      kindz(numpoint)=1
+  endif
+
+
   ! Check whether x coordinates of release point are within model domain
   !*********************************************************************