! $Id$

module regr_pr_comb_coefoz_m

  implicit none

  ! The five module variables declared here are on the partial

  ! "physics" grid.

  ! The value of each variable for index "(i, k)" is at longitude

  ! "rlon(i)", latitude "rlat(i)" and middle of layer "k".

  real, allocatable, save:: c_Mob(:, :)

  ! (sum of Mobidic terms in the net mass production rate of ozone

  ! by chemistry, per unit mass of air, in s-1)

  real, allocatable, save:: a2(:, :)

  ! (derivative of mass production rate of ozone per unit mass of

  ! air with respect to ozone mass fraction, in s-1)

  real, allocatable, save:: a4_mass(:, :)

  ! (derivative of mass production rate of ozone per unit mass of

  ! air with respect to temperature, in s-1 K-1)

  real, allocatable, save:: a6_mass(:, :)

  ! (derivative of mass production rate of ozone per unit mass of

  ! air with respect to mass column-density of ozone above, in m2 s-1 kg-1)

  real, allocatable, save:: r_het_interm(:, :)

  ! (net mass production rate by heterogeneous chemistry, per unit

  ! mass of ozone, corrected for chlorine content and latitude, but

  ! not for temperature and sun direction, in s-1)

  !$omp threadprivate(c_Mob, a2, a4_mass, a6_mass, r_het_interm)

contains

    ! This procedure is called once per run.

    ! It allocates module variables.

    use dimphy, only: klon

    use mod_grid_phy_lmdz, only: nbp_lev

    ! Variables local to the procedure:

    !---------------------------------------

    !$omp master

    !$omp end master

  !*******************************************************

    ! "regr_pr_comb_coefoz" stands for "regrid pressure combine

    ! coefficients ozone".

    ! In this subroutine:

    ! -- the master thread of the root process reads from a file all

    !    eight coefficients for ozone chemistry, at the current day;

    ! -- the coefficients are packed to the "physics" horizontal grid

    !    and scattered to all threads of all processes;

    ! -- in all the threads of all the processes, the coefficients are

    !    regridded in pressure to the LMDZ vertical grid;

    ! -- in all the threads of all the processes, the eight

    !    coefficients are combined to define the five module variables.

    use netcdf95, only: nf95_open, nf95_close

    use netcdf, only: nf90_nowrite

    use assert_m, only: assert

    use dimphy, only: klon

    use mod_phys_lmdz_mpi_data, only: is_mpi_root

    use regr_pr_time_av_m, only: regr_pr_time_av

    use regr_pr_int_m, only: regr_pr_int

    use press_coefoz_m, only: press_in_edg, plev

    use mod_grid_phy_lmdz, only: nbp_lev

    integer, intent(in):: julien ! jour julien, 1 <= julien <= 360

    REAL, intent(in):: rlat(:)

    ! (latitude on the partial "physics" grid, in degrees)

    real, intent(in):: paprs(:, :) ! (klon, nbp_lev + 1)

    ! (pression pour chaque inter-couche, en Pa)

    real, intent(in):: pplay(:, :) ! (klon, nbp_lev)

    ! (pression pour le mileu de chaque couche, en Pa)

    ! Variables local to the procedure:

    integer ncid ! for NetCDF

    ! (temporary storage for 7 ozone coefficients)

    ! (On the partial "physics" grid.

    ! "coefoz(i, k, :)" is at longitude "rlon(i)", latitude "rlat(i)",

    ! middle of layer "k".)

    real a6(klon, nbp_lev)

    ! (derivative of "P_net_Mob" with respect to column-density of ozone

    ! above, in cm2 s-1)

    ! (On the partial "physics" grid.

    ! "a6(i, k)" is at longitude "rlon(i)", latitude "rlat(i)",

    ! middle of layer "k".)

    real, parameter:: amu = 1.6605402e-27 ! atomic mass unit, in kg

    real, parameter:: Clx = 3.8e-9

    ! (total chlorine content in the upper stratosphere)

    integer k

    !------------------------------------

    !!print *, "Call sequence information: regr_pr_comb_coefoz"

    call assert((/size(rlat), size(paprs, 1), size(pplay, 1)/) == klon, &

    call assert((/size(paprs, 2) - 1, size(pplay, 2)/) == nbp_lev, &

    !$omp master

    !$omp end master

    call regr_pr_time_av(ncid, (/"a2           ", "a4           ", "a6           ", &

         "P_net_Mob    ", "r_Mob        ", "temp_Mob     ", "R_Het        "/),      &

    ! Compute "a6_mass" avoiding underflow, do not divide by 1e4

    ! before dividing by molecular mass:

    ! (factor 1e4: conversion from cm2 to m2)

    ! We can overwrite "coefoz(:, :, 1)", which was saved to "a2":

    call regr_pr_int(ncid, "Sigma_Mob", julien, plev, pplay, top_value=0., &

    ! Combine coefficients to get "c_Mob":

    c_mob = (coefoz(:, :, 4) - a2 * coefoz(:, :, 5) &

         - coefoz(:, :, 3) * coefoz(:, :, 1)) * 48. / 29. &

    ! Heterogeneous chemistry is only at high latitudes:

       where (abs(rlat) <= 45.) r_het_interm(:, k) = 0.

    end forall

    r_het_interm = r_het_interm * (Clx / 3.8e-9)**2

    !$omp master

    !$omp end master

end module regr_pr_comb_coefoz_m