SUBROUTINE read_dust(debutphy, step, nbjour, dust_ec)
  USE dimphy
  USE mod_grid_phy_lmdz
  USE mod_phys_lmdz_para
  USE netcdf, ONLY: nf90_get_var, nf90_nowrite, nf90_open, nf90_inq_varid
!!USE paramet_mod_h
IMPLICIT NONE
  !


  !
  INTEGER :: step, nbjour
  LOGICAL :: debutphy
  real :: dust_ec(klon)
  real :: dust_ec_glo(klon_glo)
  !
  ! as      real dust_nc(iip1,jjp1)
  real :: dust_nc_glo(nbp_lon+1,nbp_lat)
  INTEGER :: ncid1, varid1, ncid2, varid2, rcode

  save ncid1, varid1, ncid2, varid2
!$OMP THREADPRIVATE(ncid1, varid1, ncid2, varid2)
  integer :: start(4),count(4), status
  integer :: i, j, ig
  !
!$OMP MASTER
  IF (is_mpi_root .AND. is_omp_root) THEN
  if (debutphy) then
  !
     ncid1=nf90_open('dust.nc',nf90_nowrite,rcode)
     varid1=nf90_inq_varid(ncid1,'EMISSION',rcode)
  !
  endif
  !
  start(1)=1
  start(2)=1
  start(4)=0

   ! count(1)=iip1
  count(1)=nbp_lon+1
   ! count(2)=jjp1
  count(2)=nbp_lat
  count(3)=1
  count(4)=0
  !
  start(3)=step
  !
  status = nf90_get_var(ncid1, varid1, dust_nc_glo, start, count)

  !
  call correctbid(nbp_lon,nbp_lat,dust_nc_glo)
  !
  !--upside down + physical grid
  !
  !--OB=change jjp1 to 1 here ;
  !----AS: OB's change is needed if lats N to S (90 to -90) in dust.nc
  !  dust_ec(1)=MAX(dust_nc(1,jjp1),0.0)
  dust_ec_glo(1)=MAX(dust_nc_glo(1,nbp_lat),0.0)
  ig=2
   ! DO j=2,jjm
  DO j=2,nbp_lat-1
     DO i = 1, nbp_lon
  !--OB=change jjp1+1-j to j here
        ! dust_ec(ig)=MAX(dust_nc(i,jjp1+1-j),0.0)
       dust_ec_glo(ig)=MAX(dust_nc_glo(i,nbp_lat+1-j),0.0)
       ig=ig+1
     ENDDO
  ENDDO
  !--OB=change second 1 to jjp1 here
  dust_ec_glo(ig)=MAX(dust_nc_glo(1,1),0.0)
   ! end if master
  ENDIF
!$OMP END MASTER
!$OMP BARRIER
  CALL scatter(dust_ec_glo,dust_ec)
  !
  RETURN
END SUBROUTINE read_dust