module SNICARMod !----------------------------------------------------------------------- !BOP ! ! !MODULE: SNICARMod ! ! !DESCRIPTION: ! Calculate albedo of snow containing impurities ! and the evolution of snow effective radius ! ! !USES: use shr_kind_mod , only : r8 => shr_kind_r8 use shr_sys_mod , only : shr_sys_flush use clm_varctl , only : iulog use shr_const_mod , only : SHR_CONST_RHOICE use abortutils , only : endrun implicit none save ! ! !PUBLIC MEMBER FUNCTIONS: public :: SNICAR_RT ! Snow albedo and vertically-resolved solar absorption public :: SnowAge_grain ! Snow effective grain size evolution public :: SnowAge_init ! Initial read in of snow-aging file public :: SnowOptics_init ! Initial read in of snow-optics file ! ! !PUBLIC DATA MEMBERS: real(r8), public, parameter :: snw_rds_min = 54.526_r8 ! minimum allowed snow effective radius (also "fresh snow" value) [microns] integer, public, parameter :: sno_nbr_aer = 8 ! number of aerosol species in snowpack (indices described above) [nbr] logical, public, parameter :: DO_SNO_OC = .false. ! parameter to include organic carbon (OC) in snowpack radiative calculations logical, public, parameter :: DO_SNO_AER = .true. ! parameter to include aerosols in snowpack radiative calculations real(r8), public, parameter :: scvng_fct_mlt_bcphi = 0.20_r8 ! scavenging factor for hydrophillic BC inclusion in meltwater [frc] real(r8), public, parameter :: scvng_fct_mlt_bcpho = 0.03_r8 ! scavenging factor for hydrophobic BC inclusion in meltwater [frc] real(r8), public, parameter :: scvng_fct_mlt_ocphi = 0.20_r8 ! scavenging factor for hydrophillic OC inclusion in meltwater [frc] real(r8), public, parameter :: scvng_fct_mlt_ocpho = 0.03_r8 ! scavenging factor for hydrophobic OC inclusion in meltwater [frc] real(r8), public, parameter :: scvng_fct_mlt_dst1 = 0.02_r8 ! scavenging factor for dust species 1 inclusion in meltwater [frc] real(r8), public, parameter :: scvng_fct_mlt_dst2 = 0.02_r8 ! scavenging factor for dust species 2 inclusion in meltwater [frc] real(r8), public, parameter :: scvng_fct_mlt_dst3 = 0.01_r8 ! scavenging factor for dust species 3 inclusion in meltwater [frc] real(r8), public, parameter :: scvng_fct_mlt_dst4 = 0.01_r8 ! scavenging factor for dust species 4 inclusion in meltwater [frc] ! !PRIVATE MEMBER FUNCTIONS: ! ! !PRIVATE DATA MEMBERS: ! Aerosol species indices: ! 1= hydrophillic black carbon ! 2= hydrophobic black carbon ! 3= hydrophilic organic carbon ! 4= hydrophobic organic carbon ! 5= dust species 1 ! 6= dust species 2 ! 7= dust species 3 ! 8= dust species 4 integer, parameter :: numrad_snw = 5 ! number of spectral bands used in snow model [nbr] integer, parameter :: nir_bnd_bgn = 2 ! first band index in near-IR spectrum [idx] integer, parameter :: nir_bnd_end = 5 ! ending near-IR band index [idx] integer, parameter :: idx_Mie_snw_mx = 1471 ! number of effective radius indices used in Mie lookup table [idx] integer, parameter :: idx_T_max = 11 ! maxiumum temperature index used in aging lookup table [idx] integer, parameter :: idx_T_min = 1 ! minimum temperature index used in aging lookup table [idx] integer, parameter :: idx_Tgrd_max = 31 ! maxiumum temperature gradient index used in aging lookup table [idx] integer, parameter :: idx_Tgrd_min = 1 ! minimum temperature gradient index used in aging lookup table [idx] integer, parameter :: idx_rhos_max = 8 ! maxiumum snow density index used in aging lookup table [idx] integer, parameter :: idx_rhos_min = 1 ! minimum snow density index used in aging lookup table [idx] integer, parameter :: snw_rds_max_tbl = 1500 ! maximum effective radius defined in Mie lookup table [microns] integer, parameter :: snw_rds_min_tbl = 30 ! minimium effective radius defined in Mie lookup table [microns] real(r8), parameter :: snw_rds_max = 1500._r8 ! maximum allowed snow effective radius [microns] real(r8), parameter :: snw_rds_refrz = 1000._r8 ! effective radius of re-frozen snow [microns] real(r8), parameter :: min_snw = 1.0E-30_r8 ! minimum snow mass required for SNICAR RT calculation [kg m-2] !real(r8), parameter :: C1_liq_Brun89 = 1.28E-17_r8 ! constant for liquid water grain growth [m3 s-1], from Brun89 real(r8), parameter :: C1_liq_Brun89 = 0._r8 ! constant for liquid water grain growth [m3 s-1], from Brun89: zeroed to accomodate dry snow aging real(r8), parameter :: C2_liq_Brun89 = 4.22E-13_r8 ! constant for liquid water grain growth [m3 s-1], from Brun89: corrected for LWC in units of percent real(r8), parameter :: tim_cns_bc_rmv = 2.2E-8_r8 ! time constant for removal of BC in snow on sea-ice [s-1] (50% mass removal/year) real(r8), parameter :: tim_cns_oc_rmv = 2.2E-8_r8 ! time constant for removal of OC in snow on sea-ice [s-1] (50% mass removal/year) real(r8), parameter :: tim_cns_dst_rmv = 2.2E-8_r8 ! time constant for removal of dust in snow on sea-ice [s-1] (50% mass removal/year) ! scaling of the snow aging rate (tuning option): logical :: flg_snoage_scl = .false. ! flag for scaling the snow aging rate by some arbitrary factor real(r8), parameter :: xdrdt = 1.0_r8 ! arbitrary factor applied to snow aging rate ! snow and aerosol Mie parameters: ! (arrays declared here, but are set in iniTimeConst) ! (idx_Mie_snw_mx is number of snow radii with defined parameters (i.e. from 30um to 1500um)) ! direct-beam weighted ice optical properties real(r8) :: ss_alb_snw_drc(idx_Mie_snw_mx,numrad_snw) real(r8) :: asm_prm_snw_drc(idx_Mie_snw_mx,numrad_snw) real(r8) :: ext_cff_mss_snw_drc(idx_Mie_snw_mx,numrad_snw) ! diffuse radiation weighted ice optical properties real(r8) :: ss_alb_snw_dfs(idx_Mie_snw_mx,numrad_snw) real(r8) :: asm_prm_snw_dfs(idx_Mie_snw_mx,numrad_snw) real(r8) :: ext_cff_mss_snw_dfs(idx_Mie_snw_mx,numrad_snw) ! hydrophiliic BC real(r8) :: ss_alb_bc1(numrad_snw) real(r8) :: asm_prm_bc1(numrad_snw) real(r8) :: ext_cff_mss_bc1(numrad_snw) ! hydrophobic BC real(r8) :: ss_alb_bc2(numrad_snw) real(r8) :: asm_prm_bc2(numrad_snw) real(r8) :: ext_cff_mss_bc2(numrad_snw) ! hydrophobic OC real(r8) :: ss_alb_oc1(numrad_snw) real(r8) :: asm_prm_oc1(numrad_snw) real(r8) :: ext_cff_mss_oc1(numrad_snw) ! hydrophilic OC real(r8) :: ss_alb_oc2(numrad_snw) real(r8) :: asm_prm_oc2(numrad_snw) real(r8) :: ext_cff_mss_oc2(numrad_snw) ! dust species 1: real(r8) :: ss_alb_dst1(numrad_snw) real(r8) :: asm_prm_dst1(numrad_snw) real(r8) :: ext_cff_mss_dst1(numrad_snw) ! dust species 2: real(r8) :: ss_alb_dst2(numrad_snw) real(r8) :: asm_prm_dst2(numrad_snw) real(r8) :: ext_cff_mss_dst2(numrad_snw) ! dust species 3: real(r8) :: ss_alb_dst3(numrad_snw) real(r8) :: asm_prm_dst3(numrad_snw) real(r8) :: ext_cff_mss_dst3(numrad_snw) ! dust species 4: real(r8) :: ss_alb_dst4(numrad_snw) real(r8) :: asm_prm_dst4(numrad_snw) real(r8) :: ext_cff_mss_dst4(numrad_snw) ! best-fit parameters for snow aging defined over: ! 11 temperatures from 225 to 273 K ! 31 temperature gradients from 0 to 300 K/m ! 8 snow densities from 0 to 350 kg/m3 ! (arrays declared here, but are set in iniTimeConst) real(r8), pointer :: snowage_tau(:,:,:) ! (idx_rhos_max,idx_Tgrd_max,idx_T_max) real(r8), pointer :: snowage_kappa(:,:,:) ! (idx_rhos_max,idx_Tgrd_max,idx_T_max) real(r8), pointer :: snowage_drdt0(:,:,:) ! idx_rhos_max,idx_Tgrd_max,idx_T_max) ! ! !REVISION HISTORY: ! Created by Mark Flanner ! !EOP !----------------------------------------------------------------------- contains !----------------------------------------------------------------------- !BOP ! ! !IROUTINE: SNICAR_RT ! ! ! !CALLED FROM: ! subroutine SurfaceAlbedo in module SurfaceAlbedoMod (CLM) ! subroutine albice (CSIM) ! ! !REVISION HISTORY: ! Author: Mark Flanner ! ! !INTERFACE: subroutine SNICAR_RT (flg_snw_ice, lbc, ubc, num_nourbanc, filter_nourbanc, & coszen, flg_slr_in, h2osno_liq, h2osno_ice, snw_rds, & mss_cnc_aer_in, albsfc, albout, flx_abs) ! ! !DESCRIPTION: ! Determine reflectance of, and vertically-resolved solar absorption in, ! snow with impurities. ! ! Original references on physical models of snow reflectance include: ! Wiscombe and Warren [1980] and Warren and Wiscombe [1980], ! Journal of Atmospheric Sciences, 37, ! ! The multi-layer solution for multiple-scattering used here is from: ! Toon et al. [1989], Rapid calculation of radiative heating rates ! and photodissociation rates in inhomogeneous multiple scattering atmospheres, ! J. Geophys. Res., 94, D13, 16287-16301 ! ! The implementation of the SNICAR model in CLM/CSIM is described in: ! Flanner, M., C. Zender, J. Randerson, and P. Rasch [2007], ! Present-day climate forcing and response from black carbon in snow, ! J. Geophys. Res., 112, D11202, doi: 10.1029/2006JD008003 ! !USES: use clmtype use clm_varpar , only : nlevsno, numrad use clm_time_manager , only : get_nstep use shr_const_mod , only : SHR_CONST_PI ! ! !ARGUMENTS: implicit none integer , intent(in) :: flg_snw_ice ! flag: =1 when called from CLM, =2 when called from CSIM integer , intent(in) :: lbc, ubc ! column index bounds [unitless] integer , intent(in) :: num_nourbanc ! number of columns in non-urban filter integer , intent(in) :: filter_nourbanc(ubc-lbc+1) ! column filter for non-urban points real(r8), intent(in) :: coszen(lbc:ubc) ! cosine of solar zenith angle for next time step (col) [unitless] integer , intent(in) :: flg_slr_in ! flag: =1 for direct-beam incident flux, =2 for diffuse incident flux real(r8), intent(in) :: h2osno_liq(lbc:ubc,-nlevsno+1:0) ! liquid water content (col,lyr) [kg/m2] real(r8), intent(in) :: h2osno_ice(lbc:ubc,-nlevsno+1:0) ! ice content (col,lyr) [kg/m2] integer, intent(in) :: snw_rds(lbc:ubc,-nlevsno+1:0) ! snow effective radius (col,lyr) [microns, m^-6] real(r8), intent(in) :: mss_cnc_aer_in(lbc:ubc,-nlevsno+1:0,sno_nbr_aer) ! mass concentration of all aerosol species (col,lyr,aer) [kg/kg] real(r8), intent(in) :: albsfc(lbc:ubc,numrad) ! albedo of surface underlying snow (col,bnd) [frc] real(r8), intent(out) :: albout(lbc:ubc,numrad) ! snow albedo, averaged into 2 bands (=0 if no sun or no snow) (col,bnd) [frc] real(r8), intent(out) :: flx_abs(lbc:ubc,-nlevsno+1:1,numrad) ! absorbed flux in each layer per unit flux incident on top of snowpack (col,lyr,bnd) [frc] ! ! !LOCAL VARIABLES: ! ! local pointers to implicit in arguments ! integer, pointer :: snl(:) ! negative number of snow layers (col) [nbr] real(r8), pointer :: h2osno(:) ! snow liquid water equivalent (col) [kg/m2] integer, pointer :: clandunit(:) ! corresponding landunit of column (col) [idx] (debugging only) integer, pointer :: cgridcell(:) ! columns's gridcell index (col) [idx] (debugging only) integer, pointer :: ltype(:) ! landunit type (lnd) (debugging only) real(r8), pointer :: londeg(:) ! longitude (degrees) (debugging only) real(r8), pointer :: latdeg(:) ! latitude (degrees) (debugging only) ! ! !OTHER LOCAL VARIABLES: !EOP !----------------------------------------------------------------------- ! ! variables for snow radiative transfer calculations ! Local variables representing single-column values of arrays: integer :: snl_lcl ! negative number of snow layers [nbr] integer :: snw_rds_lcl(-nlevsno+1:0) ! snow effective radius [m^-6] real(r8):: flx_slrd_lcl(1:numrad_snw) ! direct beam incident irradiance [W/m2] (set to 1) real(r8):: flx_slri_lcl(1:numrad_snw) ! diffuse incident irradiance [W/m2] (set to 1) real(r8):: mss_cnc_aer_lcl(-nlevsno+1:0,1:sno_nbr_aer) ! aerosol mass concentration (lyr,aer_nbr) [kg/kg] real(r8):: h2osno_lcl ! total column snow mass [kg/m2] real(r8):: h2osno_liq_lcl(-nlevsno+1:0) ! liquid water mass [kg/m2] real(r8):: h2osno_ice_lcl(-nlevsno+1:0) ! ice mass [kg/m2] real(r8):: albsfc_lcl(1:numrad_snw) ! albedo of underlying surface [frc] real(r8):: ss_alb_snw_lcl(-nlevsno+1:0) ! single-scatter albedo of ice grains (lyr) [frc] real(r8):: asm_prm_snw_lcl(-nlevsno+1:0) ! asymmetry parameter of ice grains (lyr) [frc] real(r8):: ext_cff_mss_snw_lcl(-nlevsno+1:0) ! mass extinction coefficient of ice grains (lyr) [m2/kg] real(r8):: ss_alb_aer_lcl(sno_nbr_aer) ! single-scatter albedo of aerosol species (aer_nbr) [frc] real(r8):: asm_prm_aer_lcl(sno_nbr_aer) ! asymmetry parameter of aerosol species (aer_nbr) [frc] real(r8):: ext_cff_mss_aer_lcl(sno_nbr_aer) ! mass extinction coefficient of aerosol species (aer_nbr) [m2/kg] ! Other local variables integer :: APRX_TYP ! two-stream approximation type (1=Eddington, 2=Quadrature, 3=Hemispheric Mean) [nbr] integer :: DELTA ! flag to use Delta approximation (Joseph, 1976) (1= use, 0= don't use) real(r8):: flx_wgt(1:numrad_snw) ! weights applied to spectral bands, specific to direct and diffuse cases (bnd) [frc] integer :: flg_nosnl ! flag: =1 if there is snow, but zero snow layers, =0 if at least 1 snow layer [flg] integer :: trip ! flag: =1 to redo RT calculation if result is unrealistic integer :: flg_dover ! defines conditions for RT redo (explained below) real(r8):: albedo ! temporary snow albedo [frc] real(r8):: flx_sum ! temporary summation variable for NIR weighting real(r8):: albout_lcl(numrad_snw) ! snow albedo by band [frc] real(r8):: flx_abs_lcl(-nlevsno+1:1,numrad_snw)! absorbed flux per unit incident flux at top of snowpack (lyr,bnd) [frc] real(r8):: L_snw(-nlevsno+1:0) ! h2o mass (liquid+solid) in snow layer (lyr) [kg/m2] real(r8):: tau_snw(-nlevsno+1:0) ! snow optical depth (lyr) [unitless] real(r8):: L_aer(-nlevsno+1:0,sno_nbr_aer) ! aerosol mass in snow layer (lyr,nbr_aer) [kg/m2] real(r8):: tau_aer(-nlevsno+1:0,sno_nbr_aer) ! aerosol optical depth (lyr,nbr_aer) [unitless] real(r8):: tau_sum ! cumulative (snow+aerosol) optical depth [unitless] real(r8):: tau_clm(-nlevsno+1:0) ! column optical depth from layer bottom to snowpack top (lyr) [unitless] real(r8):: omega_sum ! temporary summation of single-scatter albedo of all aerosols [frc] real(r8):: g_sum ! temporary summation of asymmetry parameter of all aerosols [frc] real(r8):: tau(-nlevsno+1:0) ! weighted optical depth of snow+aerosol layer (lyr) [unitless] real(r8):: omega(-nlevsno+1:0) ! weighted single-scatter albedo of snow+aerosol layer (lyr) [frc] real(r8):: g(-nlevsno+1:0) ! weighted asymmetry parameter of snow+aerosol layer (lyr) [frc] real(r8):: tau_star(-nlevsno+1:0) ! transformed (i.e. Delta-Eddington) optical depth of snow+aerosol layer (lyr) [unitless] real(r8):: omega_star(-nlevsno+1:0) ! transformed (i.e. Delta-Eddington) SSA of snow+aerosol layer (lyr) [frc] real(r8):: g_star(-nlevsno+1:0) ! transformed (i.e. Delta-Eddington) asymmetry paramater of snow+aerosol layer (lyr) [frc] integer :: nstep ! current timestep [nbr] (debugging only) integer :: g_idx, c_idx, l_idx ! gridcell, column, and landunit indices [idx] integer :: bnd_idx ! spectral band index (1 <= bnd_idx <= numrad_snw) [idx] integer :: rds_idx ! snow effective radius index for retrieving Mie parameters from lookup table [idx] integer :: snl_btm ! index of bottom snow layer (0) [idx] integer :: snl_top ! index of top snow layer (-4 to 0) [idx] integer :: fc ! column filter index integer :: i ! layer index [idx] integer :: j ! aerosol number index [idx] integer :: n ! tridiagonal matrix index [idx] integer :: m ! secondary layer index [idx] real(r8):: F_direct(-nlevsno+1:0) ! direct-beam radiation at bottom of layer interface (lyr) [W/m^2] real(r8):: F_net(-nlevsno+1:0) ! net radiative flux at bottom of layer interface (lyr) [W/m^2] real(r8):: F_abs(-nlevsno+1:0) ! net absorbed radiative energy (lyr) [W/m^2] real(r8):: F_abs_sum ! total absorbed energy in column [W/m^2] real(r8):: F_sfc_pls ! upward radiative flux at snowpack top [W/m^2] real(r8):: F_btm_net ! net flux at bottom of snowpack [W/m^2] real(r8):: F_sfc_net ! net flux at top of snowpack [W/m^2] real(r8):: energy_sum ! sum of all energy terms; should be 0.0 [W/m^2] real(r8):: F_direct_btm ! direct-beam radiation at bottom of snowpack [W/m^2] real(r8):: mu_not ! cosine of solar zenith angle (used locally) [frc] integer :: err_idx ! counter for number of times through error loop [nbr] real(r8):: lat_coord ! gridcell latitude (debugging only) real(r8):: lon_coord ! gridcell longitude (debugging only) integer :: sfctype ! underlying surface type (debugging only) real(r8):: pi ! 3.1415... ! intermediate variables for radiative transfer approximation: real(r8):: gamma1(-nlevsno+1:0) ! two-stream coefficient from Toon et al. (lyr) [unitless] real(r8):: gamma2(-nlevsno+1:0) ! two-stream coefficient from Toon et al. (lyr) [unitless] real(r8):: gamma3(-nlevsno+1:0) ! two-stream coefficient from Toon et al. (lyr) [unitless] real(r8):: gamma4(-nlevsno+1:0) ! two-stream coefficient from Toon et al. (lyr) [unitless] real(r8):: lambda(-nlevsno+1:0) ! two-stream coefficient from Toon et al. (lyr) [unitless] real(r8):: GAMMA(-nlevsno+1:0) ! two-stream coefficient from Toon et al. (lyr) [unitless] real(r8):: mu_one ! two-stream coefficient from Toon et al. (lyr) [unitless] real(r8):: e1(-nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (lyr) real(r8):: e2(-nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (lyr) real(r8):: e3(-nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (lyr) real(r8):: e4(-nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (lyr) real(r8):: C_pls_btm(-nlevsno+1:0) ! intermediate variable: upward flux at bottom interface (lyr) [W/m2] real(r8):: C_mns_btm(-nlevsno+1:0) ! intermediate variable: downward flux at bottom interface (lyr) [W/m2] real(r8):: C_pls_top(-nlevsno+1:0) ! intermediate variable: upward flux at top interface (lyr) [W/m2] real(r8):: C_mns_top(-nlevsno+1:0) ! intermediate variable: downward flux at top interface (lyr) [W/m2] real(r8):: A(-2*nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (2*lyr) real(r8):: B(-2*nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (2*lyr) real(r8):: D(-2*nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (2*lyr) real(r8):: E(-2*nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (2*lyr) real(r8):: AS(-2*nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (2*lyr) real(r8):: DS(-2*nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (2*lyr) real(r8):: X(-2*nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (2*lyr) real(r8):: Y(-2*nlevsno+1:0) ! tri-diag intermediate variable from Toon et al. (2*lyr) ! Assign local pointers to derived subtypes components (column-level) ! (CLM-specific) if (flg_snw_ice == 1) then snl => clm3%g%l%c%cps%snl h2osno => clm3%g%l%c%cws%h2osno clandunit => clm3%g%l%c%landunit ! (debug only) cgridcell => clm3%g%l%c%gridcell ! (debug only) ltype => clm3%g%l%itype ! (debug only) londeg => clm3%g%londeg ! (debug only) latdeg => clm3%g%latdeg ! (debug only) endif ! Define constants pi = SHR_CONST_PI ! always use Delta approximation for snow DELTA = 1 ! Get current timestep nstep = get_nstep() ! Loop over all non-urban columns ! (when called from CSIM, there is only one column) do fc = 1,num_nourbanc c_idx = filter_nourbanc(fc) ! Zero absorbed radiative fluxes: do i=-nlevsno+1,1,1 flx_abs_lcl(:,:) = 0._r8 flx_abs(c_idx,i,:) = 0._r8 enddo ! set snow/ice mass to be used for RT: if (flg_snw_ice == 1) then h2osno_lcl = h2osno(c_idx) else h2osno_lcl = h2osno_ice(c_idx,0) endif ! Qualifier for computing snow RT: ! 1) sunlight from atmosphere model ! 2) minimum amount of snow on ground. ! Otherwise, set snow albedo to zero if ((coszen(c_idx) > 0._r8) .and. (h2osno_lcl > min_snw)) then ! Set variables specific to CLM if (flg_snw_ice == 1) then ! Assign local (single-column) variables to global values ! If there is snow, but zero snow layers, we must create a layer locally. ! This layer is presumed to have the fresh snow effective radius. if (snl(c_idx) > -1) then flg_nosnl = 1 snl_lcl = -1 h2osno_ice_lcl(0) = h2osno_lcl h2osno_liq_lcl(0) = 0._r8 snw_rds_lcl(0) = nint(snw_rds_min) else flg_nosnl = 0 snl_lcl = snl(c_idx) h2osno_liq_lcl(:) = h2osno_liq(c_idx,:) h2osno_ice_lcl(:) = h2osno_ice(c_idx,:) snw_rds_lcl(:) = snw_rds(c_idx,:) endif snl_btm = 0 snl_top = snl_lcl+1 ! for debugging only l_idx = clandunit(c_idx) g_idx = cgridcell(c_idx) sfctype = ltype(l_idx) lat_coord = latdeg(g_idx) lon_coord = londeg(g_idx) ! Set variables specific to CSIM else flg_nosnl = 0 snl_lcl = -1 h2osno_liq_lcl(:) = h2osno_liq(c_idx,:) h2osno_ice_lcl(:) = h2osno_ice(c_idx,:) snw_rds_lcl(:) = snw_rds(c_idx,:) snl_btm = 0 snl_top = 0 sfctype = -1 lat_coord = -90 lon_coord = 0 endif ! Set local aerosol array do j=1,sno_nbr_aer mss_cnc_aer_lcl(:,j) = mss_cnc_aer_in(c_idx,:,j) enddo ! Set spectral underlying surface albedos to their corresponding VIS or NIR albedos albsfc_lcl(1) = albsfc(c_idx,1) albsfc_lcl(nir_bnd_bgn:nir_bnd_end) = albsfc(c_idx,2) ! Error check for snow grain size: do i=snl_top,snl_btm,1 if ((snw_rds_lcl(i) < snw_rds_min_tbl) .or. (snw_rds_lcl(i) > snw_rds_max_tbl)) then write (iulog,*) "SNICAR ERROR: snow grain radius of ", snw_rds_lcl(i), " out of bounds." write (iulog,*) "NSTEP= ", nstep write (iulog,*) "flg_snw_ice= ", flg_snw_ice write (iulog,*) "column: ", c_idx, " level: ", i, " snl(c)= ", snl_lcl write (iulog,*) "lat= ", lat_coord, " lon= ", lon_coord write (iulog,*) "h2osno(c)= ", h2osno_lcl call endrun() endif enddo ! Incident flux weighting parameters ! - sum of all VIS bands must equal 1 ! - sum of all NIR bands must equal 1 ! ! Spectral bands (5-band case) ! Band 1: 0.3-0.7um (VIS) ! Band 2: 0.7-1.0um (NIR) ! Band 3: 1.0-1.2um (NIR) ! Band 4: 1.2-1.5um (NIR) ! Band 5: 1.5-5.0um (NIR) ! ! The following weights are appropriate for surface-incident flux in a mid-latitude winter atmosphere ! ! 3-band weights if (numrad_snw==3) then ! Direct: if (flg_slr_in == 1) then flx_wgt(1) = 1._r8 flx_wgt(2) = 0.66628670195247_r8 flx_wgt(3) = 0.33371329804753_r8 ! Diffuse: elseif (flg_slr_in == 2) then flx_wgt(1) = 1._r8 flx_wgt(2) = 0.77887652162877_r8 flx_wgt(3) = 0.22112347837123_r8 endif ! 5-band weights elseif(numrad_snw==5) then ! Direct: if (flg_slr_in == 1) then flx_wgt(1) = 1._r8 flx_wgt(2) = 0.49352158521175_r8 flx_wgt(3) = 0.18099494230665_r8 flx_wgt(4) = 0.12094898498813_r8 flx_wgt(5) = 0.20453448749347_r8 ! Diffuse: elseif (flg_slr_in == 2) then flx_wgt(1) = 1._r8 flx_wgt(2) = 0.58581507618433_r8 flx_wgt(3) = 0.20156903770812_r8 flx_wgt(4) = 0.10917889346386_r8 flx_wgt(5) = 0.10343699264369_r8 endif endif ! Loop over snow spectral bands do bnd_idx = 1,numrad_snw mu_not = coszen(c_idx) ! must set here, because of error handling flg_dover = 1 ! default is to redo err_idx = 0 ! number of times through loop do while (flg_dover > 0) ! DEFAULT APPROXIMATIONS: ! VIS: Delta-Eddington ! NIR (all): Delta-Hemispheric Mean ! WARNING: DO NOT USE DELTA-EDDINGTON FOR NIR DIFFUSE - this sometimes results in negative albedo ! ! ERROR CONDITIONS: ! Conditions which cause "trip", resulting in redo of RT approximation: ! 1. negative absorbed flux ! 2. total absorbed flux greater than incident flux ! 3. negative albedo ! NOTE: These errors have only been encountered in spectral bands 4 and 5 ! ! ERROR HANDLING ! 1st error (flg_dover=2): switch approximation (Edd->HM or HM->Edd) ! 2nd error (flg_dover=3): change zenith angle by 0.02 (this happens about 1 in 10^6 cases) ! 3rd error (flg_dover=4): switch approximation with new zenith ! Subsequent errors: repeatedly change zenith and approximations... if (bnd_idx == 1) then if (flg_dover == 2) then APRX_TYP = 3 elseif (flg_dover == 3) then APRX_TYP = 1 if (coszen(c_idx) > 0.5_r8) then mu_not = mu_not - 0.02_r8 else mu_not = mu_not + 0.02_r8 endif elseif (flg_dover == 4) then APRX_TYP = 3 else APRX_TYP = 1 endif else if (flg_dover == 2) then APRX_TYP = 1 elseif (flg_dover == 3) then APRX_TYP = 3 if (coszen(c_idx) > 0.5_r8) then mu_not = mu_not - 0.02_r8 else mu_not = mu_not + 0.02_r8 endif elseif (flg_dover == 4) then APRX_TYP = 1 else APRX_TYP = 3 endif endif ! Set direct or diffuse incident irradiance to 1 ! (This has to be within the bnd loop because mu_not is adjusted in rare cases) if (flg_slr_in == 1) then flx_slrd_lcl(bnd_idx) = 1._r8/(mu_not*pi) ! this corresponds to incident irradiance of 1.0 flx_slri_lcl(bnd_idx) = 0._r8 else flx_slrd_lcl(bnd_idx) = 0._r8 flx_slri_lcl(bnd_idx) = 1._r8 endif ! Pre-emptive error handling: aerosols can reap havoc on these absorptive bands. ! Since extremely high soot concentrations have a negligible effect on these bands, zero them. if ( (numrad_snw == 5).and.((bnd_idx == 5).or.(bnd_idx == 4)) ) then mss_cnc_aer_lcl(:,:) = 0._r8 endif if ( (numrad_snw == 3).and.(bnd_idx == 3) ) then mss_cnc_aer_lcl(:,:) = 0._r8 endif ! Define local Mie parameters based on snow grain size and aerosol species, ! retrieved from a lookup table. if (flg_slr_in == 1) then do i=snl_top,snl_btm,1 rds_idx = snw_rds_lcl(i) - snw_rds_min_tbl + 1 ! snow optical properties (direct radiation) ss_alb_snw_lcl(i) = ss_alb_snw_drc(rds_idx,bnd_idx) asm_prm_snw_lcl(i) = asm_prm_snw_drc(rds_idx,bnd_idx) ext_cff_mss_snw_lcl(i) = ext_cff_mss_snw_drc(rds_idx,bnd_idx) enddo elseif (flg_slr_in == 2) then do i=snl_top,snl_btm,1 rds_idx = snw_rds_lcl(i) - snw_rds_min_tbl + 1 ! snow optical properties (diffuse radiation) ss_alb_snw_lcl(i) = ss_alb_snw_dfs(rds_idx,bnd_idx) asm_prm_snw_lcl(i) = asm_prm_snw_dfs(rds_idx,bnd_idx) ext_cff_mss_snw_lcl(i) = ext_cff_mss_snw_dfs(rds_idx,bnd_idx) enddo endif ! aerosol species 1 optical properties ss_alb_aer_lcl(1) = ss_alb_bc1(bnd_idx) asm_prm_aer_lcl(1) = asm_prm_bc1(bnd_idx) ext_cff_mss_aer_lcl(1) = ext_cff_mss_bc1(bnd_idx) ! aerosol species 2 optical properties ss_alb_aer_lcl(2) = ss_alb_bc2(bnd_idx) asm_prm_aer_lcl(2) = asm_prm_bc2(bnd_idx) ext_cff_mss_aer_lcl(2) = ext_cff_mss_bc2(bnd_idx) ! aerosol species 3 optical properties ss_alb_aer_lcl(3) = ss_alb_oc1(bnd_idx) asm_prm_aer_lcl(3) = asm_prm_oc1(bnd_idx) ext_cff_mss_aer_lcl(3) = ext_cff_mss_oc1(bnd_idx) ! aerosol species 4 optical properties ss_alb_aer_lcl(4) = ss_alb_oc2(bnd_idx) asm_prm_aer_lcl(4) = asm_prm_oc2(bnd_idx) ext_cff_mss_aer_lcl(4) = ext_cff_mss_oc2(bnd_idx) ! aerosol species 5 optical properties ss_alb_aer_lcl(5) = ss_alb_dst1(bnd_idx) asm_prm_aer_lcl(5) = asm_prm_dst1(bnd_idx) ext_cff_mss_aer_lcl(5) = ext_cff_mss_dst1(bnd_idx) ! aerosol species 6 optical properties ss_alb_aer_lcl(6) = ss_alb_dst2(bnd_idx) asm_prm_aer_lcl(6) = asm_prm_dst2(bnd_idx) ext_cff_mss_aer_lcl(6) = ext_cff_mss_dst2(bnd_idx) ! aerosol species 7 optical properties ss_alb_aer_lcl(7) = ss_alb_dst3(bnd_idx) asm_prm_aer_lcl(7) = asm_prm_dst3(bnd_idx) ext_cff_mss_aer_lcl(7) = ext_cff_mss_dst3(bnd_idx) ! aerosol species 8 optical properties ss_alb_aer_lcl(8) = ss_alb_dst4(bnd_idx) asm_prm_aer_lcl(8) = asm_prm_dst4(bnd_idx) ext_cff_mss_aer_lcl(8) = ext_cff_mss_dst4(bnd_idx) ! 1. snow and aerosol layer column mass (L_snw, L_aer [kg/m^2]) ! 2. optical Depths (tau_snw, tau_aer) ! 3. weighted Mie properties (tau, omega, g) ! Weighted Mie parameters of each layer do i=snl_top,snl_btm,1 L_snw(i) = h2osno_ice_lcl(i)+h2osno_liq_lcl(i) tau_snw(i) = L_snw(i)*ext_cff_mss_snw_lcl(i) do j=1,sno_nbr_aer L_aer(i,j) = L_snw(i)*mss_cnc_aer_lcl(i,j) tau_aer(i,j) = L_aer(i,j)*ext_cff_mss_aer_lcl(j) enddo tau_sum = 0._r8 omega_sum = 0._r8 g_sum = 0._r8 do j=1,sno_nbr_aer tau_sum = tau_sum + tau_aer(i,j) omega_sum = omega_sum + (tau_aer(i,j)*ss_alb_aer_lcl(j)) g_sum = g_sum + (tau_aer(i,j)*ss_alb_aer_lcl(j)*asm_prm_aer_lcl(j)) enddo tau(i) = tau_sum + tau_snw(i) omega(i) = (1/tau(i))*(omega_sum+(ss_alb_snw_lcl(i)*tau_snw(i))) g(i) = (1/(tau(i)*omega(i)))*(g_sum+ (asm_prm_snw_lcl(i)*ss_alb_snw_lcl(i)*tau_snw(i))) enddo ! DELTA transformations, if requested if (DELTA == 1) then do i=snl_top,snl_btm,1 g_star(i) = g(i)/(1+g(i)) omega_star(i) = ((1-(g(i)**2))*omega(i)) / (1-(omega(i)*(g(i)**2))) tau_star(i) = (1-(omega(i)*(g(i)**2)))*tau(i) enddo else do i=snl_top,snl_btm,1 g_star(i) = g(i) omega_star(i) = omega(i) tau_star(i) = tau(i) enddo endif ! Total column optical depth: ! tau_clm(i) = total optical depth above the bottom of layer i tau_clm(snl_top) = 0._r8 do i=snl_top+1,snl_btm,1 tau_clm(i) = tau_clm(i-1)+tau_star(i-1) enddo ! Direct radiation at bottom of snowpack: F_direct_btm = albsfc_lcl(bnd_idx)*mu_not*exp(-(tau_clm(snl_btm)+tau_star(snl_btm))/mu_not)*pi*flx_slrd_lcl(bnd_idx) ! Intermediates ! Gamma values are approximation-specific. ! Eddington if (APRX_TYP==1) then do i=snl_top,snl_btm,1 gamma1(i) = (7-(omega_star(i)*(4+(3*g_star(i)))))/4 gamma2(i) = -(1-(omega_star(i)*(4-(3*g_star(i)))))/4 gamma3(i) = (2-(3*g_star(i)*mu_not))/4 gamma4(i) = 1-gamma3(i) mu_one = 0.5 enddo ! Quadrature elseif (APRX_TYP==2) then do i=snl_top,snl_btm,1 gamma1(i) = (3**0.5)*(2-(omega_star(i)*(1+g_star(i))))/2 gamma2(i) = omega_star(i)*(3**0.5)*(1-g_star(i))/2 gamma3(i) = (1-((3**0.5)*g_star(i)*mu_not))/2 gamma4(i) = 1-gamma3(i) mu_one = 1/(3**0.5) enddo ! Hemispheric Mean elseif (APRX_TYP==3) then do i=snl_top,snl_btm,1 gamma1(i) = 2 - (omega_star(i)*(1+g_star(i))) gamma2(i) = omega_star(i)*(1-g_star(i)) gamma3(i) = (1-((3**0.5)*g_star(i)*mu_not))/2 gamma4(i) = 1-gamma3(i) mu_one = 0.5 enddo endif ! Intermediates for tri-diagonal solution do i=snl_top,snl_btm,1 lambda(i) = sqrt(abs((gamma1(i)**2) - (gamma2(i)**2))) GAMMA(i) = gamma2(i)/(gamma1(i)+lambda(i)) e1(i) = 1+(GAMMA(i)*exp(-lambda(i)*tau_star(i))) e2(i) = 1-(GAMMA(i)*exp(-lambda(i)*tau_star(i))) e3(i) = GAMMA(i) + exp(-lambda(i)*tau_star(i)) e4(i) = GAMMA(i) - exp(-lambda(i)*tau_star(i)) enddo !enddo over snow layers ! Intermediates for tri-diagonal solution do i=snl_top,snl_btm,1 if (flg_slr_in == 1) then C_pls_btm(i) = (omega_star(i)*pi*flx_slrd_lcl(bnd_idx)* & exp(-(tau_clm(i)+tau_star(i))/mu_not)* & (((gamma1(i)-(1/mu_not))*gamma3(i))+ & (gamma4(i)*gamma2(i))))/((lambda(i)**2)-(1/(mu_not**2))) C_mns_btm(i) = (omega_star(i)*pi*flx_slrd_lcl(bnd_idx)* & exp(-(tau_clm(i)+tau_star(i))/mu_not)* & (((gamma1(i)+(1/mu_not))*gamma4(i))+ & (gamma2(i)*gamma3(i))))/((lambda(i)**2)-(1/(mu_not**2))) C_pls_top(i) = (omega_star(i)*pi*flx_slrd_lcl(bnd_idx)* & exp(-tau_clm(i)/mu_not)*(((gamma1(i)-(1/mu_not))* & gamma3(i))+(gamma4(i)*gamma2(i))))/((lambda(i)**2)-(1/(mu_not**2))) C_mns_top(i) = (omega_star(i)*pi*flx_slrd_lcl(bnd_idx)* & exp(-tau_clm(i)/mu_not)*(((gamma1(i)+(1/mu_not))* & gamma4(i))+(gamma2(i)*gamma3(i))))/((lambda(i)**2)-(1/(mu_not**2))) else C_pls_btm(i) = 0._r8 C_mns_btm(i) = 0._r8 C_pls_top(i) = 0._r8 C_mns_top(i) = 0._r8 endif enddo ! Coefficients for tridiaganol matrix solution do i=2*snl_lcl+1,0,1 !Boundary values for i=1 and i=2*snl_lcl, specifics for i=odd and i=even if (i==(2*snl_lcl+1)) then A(i) = 0 B(i) = e1(snl_top) D(i) = -e2(snl_top) E(i) = flx_slri_lcl(bnd_idx)-C_mns_top(snl_top) elseif(i==0) then A(i) = e1(snl_btm)-(albsfc_lcl(bnd_idx)*e3(snl_btm)) B(i) = e2(snl_btm)-(albsfc_lcl(bnd_idx)*e4(snl_btm)) D(i) = 0 E(i) = F_direct_btm-C_pls_btm(snl_btm)+(albsfc_lcl(bnd_idx)*C_mns_btm(snl_btm)) elseif(mod(i,2)==-1) then ! If odd and i>=3 (n=1 for i=3) n=floor(i/2.0) A(i) = (e2(n)*e3(n))-(e4(n)*e1(n)) B(i) = (e1(n)*e1(n+1))-(e3(n)*e3(n+1)) D(i) = (e3(n)*e4(n+1))-(e1(n)*e2(n+1)) E(i) = (e3(n)*(C_pls_top(n+1)-C_pls_btm(n)))+(e1(n)*(C_mns_btm(n)-C_mns_top(n+1))) elseif(mod(i,2)==0) then ! If even and i<=2*snl_lcl n=(i/2) A(i) = (e2(n+1)*e1(n))-(e3(n)*e4(n+1)) B(i) = (e2(n)*e2(n+1))-(e4(n)*e4(n+1)) D(i) = (e1(n+1)*e4(n+1))-(e2(n+1)*e3(n+1)) E(i) = (e2(n+1)*(C_pls_top(n+1)-C_pls_btm(n)))+(e4(n+1)*(C_mns_top(n+1)-C_mns_btm(n))) endif enddo AS(0) = A(0)/B(0) DS(0) = E(0)/B(0) do i=-1,(2*snl_lcl+1),-1 X(i) = 1/(B(i)-(D(i)*AS(i+1))) AS(i) = A(i)*X(i) DS(i) = (E(i)-(D(i)*DS(i+1)))*X(i) enddo Y(2*snl_lcl+1) = DS(2*snl_lcl+1) do i=(2*snl_lcl+2),0,1 Y(i) = DS(i)-(AS(i)*Y(i-1)) enddo ! Downward direct-beam and net flux (F_net) at the base of each layer: do i=snl_top,snl_btm,1 F_direct(i) = mu_not*pi*flx_slrd_lcl(bnd_idx)*exp(-(tau_clm(i)+tau_star(i))/mu_not) F_net(i) = (Y(2*i-1)*(e1(i)-e3(i))) + (Y(2*i)*(e2(i)-e4(i))) + & C_pls_btm(i) - C_mns_btm(i) - F_direct(i) enddo ! Upward flux at snowpack top: F_sfc_pls = (Y(2*snl_lcl+1)*(exp(-lambda(snl_top)*tau_star(snl_top))+ & GAMMA(snl_top))) + (Y(2*snl_lcl+2)*(exp(-lambda(snl_top)* & tau_star(snl_top))-GAMMA(snl_top))) + C_pls_top(snl_top) ! Net flux at bottom = absorbed radiation by underlying surface: F_btm_net = -F_net(snl_btm) ! Bulk column albedo and surface net flux albedo = F_sfc_pls/((mu_not*pi*flx_slrd_lcl(bnd_idx))+flx_slri_lcl(bnd_idx)) F_sfc_net = F_sfc_pls - ((mu_not*pi*flx_slrd_lcl(bnd_idx))+flx_slri_lcl(bnd_idx)) trip = 0 ! Absorbed flux in each layer do i=snl_top,snl_btm,1 if(i==snl_top) then F_abs(i) = F_net(i)-F_sfc_net else F_abs(i) = F_net(i)-F_net(i-1) endif flx_abs_lcl(i,bnd_idx) = F_abs(i) ! ERROR check: negative absorption if (flx_abs_lcl(i,bnd_idx) < -0.00001) then trip = 1 endif enddo flx_abs_lcl(1,bnd_idx) = F_btm_net if (flg_nosnl == 1) then ! If there are no snow layers (but still snow), all absorbed energy must be in top soil layer !flx_abs_lcl(:,bnd_idx) = 0._r8 !flx_abs_lcl(1,bnd_idx) = F_abs(0) + F_btm_net ! changed on 20070408: ! OK to put absorbed energy in the fictitous snow layer because routine SurfaceRadiation ! handles the case of no snow layers. Then, if a snow layer is addded between now and ! SurfaceRadiation (called in Hydrology1), absorbed energy will be properly distributed. flx_abs_lcl(0,bnd_idx) = F_abs(0) flx_abs_lcl(1,bnd_idx) = F_btm_net endif !Underflow check (we've already tripped the error condition above) do i=snl_top,1,1 if (flx_abs_lcl(i,bnd_idx) < 0._r8) then flx_abs_lcl(i,bnd_idx) = 0._r8 endif enddo F_abs_sum = 0._r8 do i=snl_top,snl_btm,1 F_abs_sum = F_abs_sum + F_abs(i) enddo !ERROR check: absorption greater than incident flux ! (should make condition more generic than "1._r8") if (F_abs_sum > 1._r8) then trip = 1 endif !ERROR check: if ((albedo < 0._r8).and.(trip==0)) then trip = 1 endif ! Set conditions for redoing RT calculation if ((trip == 1).and.(flg_dover == 1)) then flg_dover = 2 elseif ((trip == 1).and.(flg_dover == 2)) then flg_dover = 3 elseif ((trip == 1).and.(flg_dover == 3)) then flg_dover = 4 elseif((trip == 1).and.(flg_dover == 4).and.(err_idx < 20)) then flg_dover = 3 err_idx = err_idx + 1 elseif((trip == 1).and.(flg_dover == 4).and.(err_idx >= 20)) then flg_dover = 0 write(iulog,*) "SNICAR ERROR: FOUND A WORMHOLE. STUCK IN INFINITE LOOP! Called from: ", flg_snw_ice write(iulog,*) "SNICAR STATS: snw_rds(0)= ", snw_rds(c_idx,0) write(iulog,*) "SNICAR STATS: L_snw(0)= ", L_snw(0) write(iulog,*) "SNICAR STATS: h2osno= ", h2osno_lcl, " snl= ", snl_lcl write(iulog,*) "SNICAR STATS: soot1(0)= ", mss_cnc_aer_lcl(0,1) write(iulog,*) "SNICAR STATS: soot2(0)= ", mss_cnc_aer_lcl(0,2) write(iulog,*) "SNICAR STATS: dust1(0)= ", mss_cnc_aer_lcl(0,3) write(iulog,*) "SNICAR STATS: dust2(0)= ", mss_cnc_aer_lcl(0,4) write(iulog,*) "SNICAR STATS: dust3(0)= ", mss_cnc_aer_lcl(0,5) write(iulog,*) "SNICAR STATS: dust4(0)= ", mss_cnc_aer_lcl(0,6) call endrun() else flg_dover = 0 endif enddo !enddo while (flg_dover > 0) ! Energy conservation check: ! Incident direct+diffuse radiation equals (absorbed+bulk_transmitted+bulk_reflected) energy_sum = (mu_not*pi*flx_slrd_lcl(bnd_idx)) + flx_slri_lcl(bnd_idx) - (F_abs_sum + F_btm_net + F_sfc_pls) if (abs(energy_sum) > 0.00001_r8) then write (iulog,"(a,e12.6,a,i6,a,i6)") "SNICAR ERROR: Energy conservation error of : ", energy_sum, & " at timestep: ", nstep, " at column: ", c_idx call endrun() endif albout_lcl(bnd_idx) = albedo ! Check that albedo is less than 1 if (albout_lcl(bnd_idx) > 1.0) then write (iulog,*) "SNICAR ERROR: Albedo > 1.0 at c: ", c_idx, " NSTEP= ",nstep write (iulog,*) "SNICAR STATS: bnd_idx= ",bnd_idx write (iulog,*) "SNICAR STATS: albout_lcl(bnd)= ",albout_lcl(bnd_idx), " albsfc_lcl(bnd_idx)= ",albsfc_lcl(bnd_idx) write (iulog,*) "SNICAR STATS: landtype= ", sfctype write (iulog,*) "SNICAR STATS: h2osno= ", h2osno_lcl, " snl= ", snl_lcl write (iulog,*) "SNICAR STATS: coszen= ", coszen(c_idx), " flg_slr= ", flg_slr_in write (iulog,*) "SNICAR STATS: soot(-4)= ", mss_cnc_aer_lcl(-4,1) write (iulog,*) "SNICAR STATS: soot(-3)= ", mss_cnc_aer_lcl(-3,1) write (iulog,*) "SNICAR STATS: soot(-2)= ", mss_cnc_aer_lcl(-2,1) write (iulog,*) "SNICAR STATS: soot(-1)= ", mss_cnc_aer_lcl(-1,1) write (iulog,*) "SNICAR STATS: soot(0)= ", mss_cnc_aer_lcl(0,1) write (iulog,*) "SNICAR STATS: L_snw(-4)= ", L_snw(-4) write (iulog,*) "SNICAR STATS: L_snw(-3)= ", L_snw(-3) write (iulog,*) "SNICAR STATS: L_snw(-2)= ", L_snw(-2) write (iulog,*) "SNICAR STATS: L_snw(-1)= ", L_snw(-1) write (iulog,*) "SNICAR STATS: L_snw(0)= ", L_snw(0) write (iulog,*) "SNICAR STATS: snw_rds(-4)= ", snw_rds(c_idx,-4) write (iulog,*) "SNICAR STATS: snw_rds(-3)= ", snw_rds(c_idx,-3) write (iulog,*) "SNICAR STATS: snw_rds(-2)= ", snw_rds(c_idx,-2) write (iulog,*) "SNICAR STATS: snw_rds(-1)= ", snw_rds(c_idx,-1) write (iulog,*) "SNICAR STATS: snw_rds(0)= ", snw_rds(c_idx,0) call endrun() endif enddo ! loop over wvl bands ! Weight output NIR albedo appropriately albout(c_idx,1) = albout_lcl(1) flx_sum = 0._r8 do bnd_idx= nir_bnd_bgn,nir_bnd_end flx_sum = flx_sum + flx_wgt(bnd_idx)*albout_lcl(bnd_idx) end do albout(c_idx,2) = flx_sum / sum(flx_wgt(nir_bnd_bgn:nir_bnd_end)) ! Weight output NIR absorbed layer fluxes (flx_abs) appropriately flx_abs(c_idx,:,1) = flx_abs_lcl(:,1) do i=snl_top,1,1 flx_sum = 0._r8 do bnd_idx= nir_bnd_bgn,nir_bnd_end flx_sum = flx_sum + flx_wgt(bnd_idx)*flx_abs_lcl(i,bnd_idx) enddo flx_abs(c_idx,i,2) = flx_sum / sum(flx_wgt(nir_bnd_bgn:nir_bnd_end)) end do ! If snow < minimum_snow, but > 0, and there is sun, set albedo to underlying surface albedo elseif ( (coszen(c_idx) > 0._r8) .and. (h2osno_lcl < min_snw) .and. (h2osno_lcl > 0._r8) ) then albout(c_idx,1) = albsfc(c_idx,1) albout(c_idx,2) = albsfc(c_idx,2) ! There is either zero snow, or no sun else albout(c_idx,1) = 0._r8 albout(c_idx,2) = 0._r8 endif ! if column has snow and coszen > 0 enddo ! loop over all columns end subroutine SNICAR_RT !----------------------------------------------------------------------- !BOP ! ! !IROUTINE: SnowAge_grain ! ! !INTERFACE: subroutine SnowAge_grain(lbc, ubc, num_snowc, filter_snowc, num_nosnowc, filter_nosnowc) ! ! !DESCRIPTION: ! Updates the snow effective grain size (radius). ! Contributions to grain size evolution are from: ! 1. vapor redistribution (dry snow) ! 2. liquid water redistribution (wet snow) ! 3. re-freezing of liquid water ! ! Vapor redistribution: Method is to retrieve 3 best-bit parameters that ! depend on snow temperature, temperature gradient, and density, ! that are derived from the microphysical model described in: ! Flanner and Zender (2006), Linking snowpack microphysics and albedo ! evolution, J. Geophys. Res., 111, D12208, doi:10.1029/2005JD006834. ! The parametric equation has the form: ! dr/dt = drdt_0*(tau/(dr_fresh+tau))^(1/kappa), where: ! r is the effective radius, ! tau and kappa are best-fit parameters, ! drdt_0 is the initial rate of change of effective radius, and ! dr_fresh is the difference between the current and fresh snow states ! (r_current - r_fresh). ! ! Liquid water redistribution: Apply the grain growth function from: ! Brun, E. (1989), Investigation of wet-snow metamorphism in respect of ! liquid-water content, Annals of Glaciology, 13, 22-26. ! There are two parameters that describe the grain growth rate as ! a function of snow liquid water content (LWC). The "LWC=0" parameter ! is zeroed here because we are accounting for dry snowing with a ! different representation ! ! Re-freezing of liquid water: Assume that re-frozen liquid water clumps ! into an arbitrarily large effective grain size (snw_rds_refrz). ! The phenomenon is observed (Grenfell), but so far unquantified, as far as ! I am aware. ! ! ! !USES: use clmtype use clm_time_manager , only : get_step_size, get_nstep use clm_varpar , only : nlevsno use clm_varcon , only : spval use abortutils , only : endrun use shr_const_mod , only : SHR_CONST_RHOICE, SHR_CONST_PI ! ! !ARGUMENTS: implicit none integer, intent(in) :: lbc, ubc ! column bounds integer, intent(in) :: num_snowc ! number of column snow points in column filter integer, intent(in) :: filter_snowc(ubc-lbc+1) ! column filter for snow points integer, intent(in) :: num_nosnowc ! number of column non-snow points in column filter integer, intent(in) :: filter_nosnowc(ubc-lbc+1) ! column filter for non-snow points ! ! ! !CALLED FROM: clm_driver1 ! ! !LOCAL VARIABLES: ! ! local pointers to implicit arguments ! real(r8), pointer :: t_soisno(:,:) ! soil and snow temperature (col,lyr) [K] integer, pointer :: snl(:) ! negative number of snow layers (col) [nbr] real(r8), pointer :: t_grnd(:) ! ground temperature (col) [K] real(r8), pointer :: dz(:,:) ! layer thickness (col,lyr) [m] real(r8), pointer :: h2osno(:) ! snow water (col) [mm H2O] real(r8), pointer :: snw_rds(:,:) ! effective grain radius (col,lyr) [microns, m-6] real(r8), pointer :: snw_rds_top(:) ! effective grain radius, top layer (col) [microns, m-6] real(r8), pointer :: sno_liq_top(:) ! liquid water fraction (mass) in top snow layer (col) [frc] real(r8), pointer :: h2osoi_liq(:,:) ! liquid water content (col,lyr) [kg m-2] real(r8), pointer :: h2osoi_ice(:,:) ! ice content (col,lyr) [kg m-2] real(r8), pointer :: snot_top(:) ! snow temperature in top layer (col) [K] real(r8), pointer :: dTdz_top(:) ! temperature gradient in top layer (col) [K m-1] real(r8), pointer :: qflx_snow_grnd_col(:) ! snow on ground after interception (col) [kg m-2 s-1] real(r8), pointer :: qflx_snwcp_ice(:) ! excess precipitation due to snow capping [kg m-2 s-1] real(r8), pointer :: qflx_snofrz_lyr(:,:) ! snow freezing rate (col,lyr) [kg m-2 s-1] logical , pointer :: do_capsnow(:) ! true => do snow capping ! ! !OTHER LOCAL VARIABLES: ! integer :: snl_top ! top snow layer index [idx] integer :: snl_btm ! bottom snow layer index [idx] integer :: i ! layer index [idx] integer :: c_idx ! column index [idx] integer :: fc ! snow column filter index [idx] integer :: T_idx ! snow aging lookup table temperature index [idx] integer :: Tgrd_idx ! snow aging lookup table temperature gradient index [idx] integer :: rhos_idx ! snow aging lookup table snow density index [idx] real(r8) :: t_snotop ! temperature at upper layer boundary [K] real(r8) :: t_snobtm ! temperature at lower layer boundary [K] real(r8) :: dTdz(lbc:ubc,-nlevsno:0) ! snow temperature gradient (col,lyr) [K m-1] real(r8) :: bst_tau ! snow aging parameter retrieved from lookup table [hour] real(r8) :: bst_kappa ! snow aging parameter retrieved from lookup table [unitless] real(r8) :: bst_drdt0 ! snow aging parameter retrieved from lookup table [um hr-1] real(r8) :: dr ! incremental change in snow effective radius [um] real(r8) :: dr_wet ! incremental change in snow effective radius from wet growth [um] real(r8) :: dr_fresh ! difference between fresh snow r_e and current r_e [um] real(r8) :: newsnow ! fresh snowfall [kg m-2] real(r8) :: refrzsnow ! re-frozen snow [kg m-2] real(r8) :: frc_newsnow ! fraction of layer mass that is new snow [frc] real(r8) :: frc_oldsnow ! fraction of layer mass that is old snow [frc] real(r8) :: frc_refrz ! fraction of layer mass that is re-frozen snow [frc] real(r8) :: frc_liq ! fraction of layer mass that is liquid water[frc] real(r8) :: dtime ! land model time step [sec] real(r8) :: rhos ! snow density [kg m-3] real(r8) :: h2osno_lyr ! liquid + solid H2O in snow layer [kg m-2] ! Assign local pointers to derived subtypes components (column-level) t_soisno => clm3%g%l%c%ces%t_soisno snl => clm3%g%l%c%cps%snl t_grnd => clm3%g%l%c%ces%t_grnd dz => clm3%g%l%c%cps%dz h2osno => clm3%g%l%c%cws%h2osno snw_rds => clm3%g%l%c%cps%snw_rds h2osoi_liq => clm3%g%l%c%cws%h2osoi_liq h2osoi_ice => clm3%g%l%c%cws%h2osoi_ice snot_top => clm3%g%l%c%cps%snot_top dTdz_top => clm3%g%l%c%cps%dTdz_top snw_rds_top => clm3%g%l%c%cps%snw_rds_top sno_liq_top => clm3%g%l%c%cps%sno_liq_top qflx_snow_grnd_col => clm3%g%l%c%cwf%pwf_a%qflx_snow_grnd qflx_snwcp_ice => clm3%g%l%c%cwf%pwf_a%qflx_snwcp_ice qflx_snofrz_lyr => clm3%g%l%c%cwf%qflx_snofrz_lyr do_capsnow => clm3%g%l%c%cps%do_capsnow ! set timestep and step interval dtime = get_step_size() ! loop over columns that have at least one snow layer do fc = 1, num_snowc c_idx = filter_snowc(fc) snl_btm = 0 snl_top = snl(c_idx) + 1 ! loop over snow layers do i=snl_top,snl_btm,1 ! !********** 1. DRY SNOW AGING *********** ! h2osno_lyr = h2osoi_liq(c_idx,i) + h2osoi_ice(c_idx,i) ! temperature gradient if (i == snl_top) then ! top layer t_snotop = t_grnd(c_idx) t_snobtm = (t_soisno(c_idx,i+1)*dz(c_idx,i) + t_soisno(c_idx,i)*dz(c_idx,i+1)) / (dz(c_idx,i)+dz(c_idx,i+1)) else t_snotop = (t_soisno(c_idx,i-1)*dz(c_idx,i) + t_soisno(c_idx,i)*dz(c_idx,i-1)) / (dz(c_idx,i)+dz(c_idx,i-1)) t_snobtm = (t_soisno(c_idx,i+1)*dz(c_idx,i) + t_soisno(c_idx,i)*dz(c_idx,i+1)) / (dz(c_idx,i)+dz(c_idx,i+1)) endif dTdz(c_idx,i) = abs((t_snotop - t_snobtm) / dz(c_idx,i)) ! snow density rhos = (h2osoi_liq(c_idx,i)+h2osoi_ice(c_idx,i)) / dz(c_idx,i) ! best-fit table indecies T_idx = nint((t_soisno(c_idx,i)-223) / 5) + 1 Tgrd_idx = nint(dTdz(c_idx,i) / 10) + 1 rhos_idx = nint((rhos-50) / 50) + 1 ! boundary check: if (T_idx < idx_T_min) then T_idx = idx_T_min endif if (T_idx > idx_T_max) then T_idx = idx_T_max endif if (Tgrd_idx < idx_Tgrd_min) then Tgrd_idx = idx_Tgrd_min endif if (Tgrd_idx > idx_Tgrd_max) then Tgrd_idx = idx_Tgrd_max endif if (rhos_idx < idx_rhos_min) then rhos_idx = idx_rhos_min endif if (rhos_idx > idx_rhos_max) then rhos_idx = idx_rhos_max endif ! best-fit parameters bst_tau = snowage_tau(rhos_idx,Tgrd_idx,T_idx) bst_kappa = snowage_kappa(rhos_idx,Tgrd_idx,T_idx) bst_drdt0 = snowage_drdt0(rhos_idx,Tgrd_idx,T_idx) ! change in snow effective radius, using best-fit parameters dr_fresh = snw_rds(c_idx,i)-snw_rds_min dr = (bst_drdt0*(bst_tau/(dr_fresh+bst_tau))**(1/bst_kappa)) * (dtime/3600) ! !********** 2. WET SNOW AGING *********** ! ! We are assuming wet and dry evolution occur simultaneously, and ! the contributions from both can be summed. ! This is justified by setting the linear offset constant C1_liq_Brun89 to zero [Brun, 1989] ! liquid water faction frc_liq = min(0.1_r8, (h2osoi_liq(c_idx,i) / (h2osoi_liq(c_idx,i)+h2osoi_ice(c_idx,i)))) !dr_wet = 1E6_r8*(dtime*(C1_liq_Brun89 + C2_liq_Brun89*(frc_liq**(3))) / (4*SHR_CONST_PI*(snw_rds(c_idx,i)/1E6)**(2))) !simplified, units of microns: dr_wet = 1E18_r8*(dtime*(C2_liq_Brun89*(frc_liq**(3))) / (4*SHR_CONST_PI*snw_rds(c_idx,i)**(2))) dr = dr + dr_wet ! !********** 3. SNOWAGE SCALING (TURNED OFF BY DEFAULT) ************* ! ! Multiply rate of change of effective radius by some constant, xdrdt if (flg_snoage_scl) then dr = dr*xdrdt endif ! !********** 4. INCREMENT EFFECTIVE RADIUS, ACCOUNTING FOR: *********** ! DRY AGING ! WET AGING ! FRESH SNOW ! RE-FREEZING ! ! new snowfall [kg/m2] if (do_capsnow(c_idx)) then newsnow = max(0._r8, (qflx_snwcp_ice(c_idx)*dtime)) else newsnow = max(0._r8, (qflx_snow_grnd_col(c_idx)*dtime)) endif ! snow that has re-frozen [kg/m2] refrzsnow = max(0._r8, (qflx_snofrz_lyr(c_idx,i)*dtime)) ! fraction of layer mass that is re-frozen frc_refrz = refrzsnow / h2osno_lyr ! fraction of layer mass that is new snow if (i == snl_top) then frc_newsnow = newsnow / h2osno_lyr else frc_newsnow = 0._r8 endif if ((frc_refrz + frc_newsnow) > 1._r8) then frc_refrz = frc_refrz / (frc_refrz + frc_newsnow) frc_newsnow = 1._r8 - frc_refrz frc_oldsnow = 0._r8 else frc_oldsnow = 1._r8 - frc_refrz - frc_newsnow endif ! mass-weighted mean of fresh snow, old snow, and re-frozen snow effective radius snw_rds(c_idx,i) = (snw_rds(c_idx,i)+dr)*frc_oldsnow + snw_rds_min*frc_newsnow + snw_rds_refrz*frc_refrz ! !********** 5. CHECK BOUNDARIES *********** ! ! boundary check if (snw_rds(c_idx,i) < snw_rds_min) then snw_rds(c_idx,i) = snw_rds_min endif if (snw_rds(c_idx,i) > snw_rds_max) then snw_rds(c_idx,i) = snw_rds_max end if ! set top layer variables for history files if (i == snl_top) then snot_top(c_idx) = t_soisno(c_idx,i) dTdz_top(c_idx) = dTdz(c_idx,i) snw_rds_top(c_idx) = snw_rds(c_idx,i) sno_liq_top(c_idx) = h2osoi_liq(c_idx,i) / (h2osoi_liq(c_idx,i)+h2osoi_ice(c_idx,i)) endif enddo enddo ! Special case: snow on ground, but not enough to have defined a snow layer: ! set snw_rds to fresh snow grain size: do fc = 1, num_nosnowc c_idx = filter_nosnowc(fc) if (h2osno(c_idx) > 0._r8) then snw_rds(c_idx,0) = snw_rds_min endif enddo end subroutine SnowAge_grain subroutine SnowOptics_init( ) use fileutils , only : getfil use CLM_varctl , only : fsnowoptics use spmdMod , only : masterproc use ncdio_pio , only : file_desc_t, ncd_io, ncd_pio_openfile, ncd_pio_closefile type(file_desc_t) :: ncid ! netCDF file id character(len=256) :: locfn ! local filename character(len= 32) :: subname = 'SnowOptics_init' ! subroutine name integer :: ier ! error status ! ! Open optics file: if(masterproc) write(iulog,*) 'Attempting to read snow optical properties .....' call getfil (fsnowoptics, locfn, 0) call ncd_pio_openfile(ncid, locfn, 0) if(masterproc) write(iulog,*) subname,trim(fsnowoptics) ! direct-beam snow Mie parameters: call ncd_io('ss_alb_ice_drc', ss_alb_snw_drc, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_ice_drc',asm_prm_snw_drc, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_ice_drc', ext_cff_mss_snw_drc, 'read', ncid, posNOTonfile=.true.) ! diffuse snow Mie parameters call ncd_io( 'ss_alb_ice_dfs', ss_alb_snw_dfs, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_ice_dfs', asm_prm_snw_dfs, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_ice_dfs', ext_cff_mss_snw_dfs, 'read', ncid, posNOTonfile=.true.) ! BC species 1 Mie parameters call ncd_io( 'ss_alb_bcphil', ss_alb_bc1, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_bcphil', asm_prm_bc1, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_bcphil', ext_cff_mss_bc1, 'read', ncid, posNOTonfile=.true.) ! BC species 2 Mie parameters call ncd_io( 'ss_alb_bcphob', ss_alb_bc2, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_bcphob', asm_prm_bc2, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_bcphob', ext_cff_mss_bc2, 'read', ncid, posNOTonfile=.true.) ! OC species 1 Mie parameters call ncd_io( 'ss_alb_ocphil', ss_alb_oc1, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_ocphil', asm_prm_oc1, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_ocphil', ext_cff_mss_oc1, 'read', ncid, posNOTonfile=.true.) ! OC species 2 Mie parameters call ncd_io( 'ss_alb_ocphob', ss_alb_oc2, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_ocphob', asm_prm_oc2, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_ocphob', ext_cff_mss_oc2, 'read', ncid, posNOTonfile=.true.) ! dust species 1 Mie parameters call ncd_io( 'ss_alb_dust01', ss_alb_dst1, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_dust01', asm_prm_dst1, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_dust01', ext_cff_mss_dst1, 'read', ncid, posNOTonfile=.true.) ! dust species 2 Mie parameters call ncd_io( 'ss_alb_dust02', ss_alb_dst2, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_dust02', asm_prm_dst2, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_dust02', ext_cff_mss_dst2, 'read', ncid, posNOTonfile=.true.) ! dust species 3 Mie parameters call ncd_io( 'ss_alb_dust03', ss_alb_dst3, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_dust03', asm_prm_dst3, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_dust03', ext_cff_mss_dst3, 'read', ncid, posNOTonfile=.true.) ! dust species 4 Mie parameters call ncd_io( 'ss_alb_dust04', ss_alb_dst4, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'asm_prm_dust04', asm_prm_dst4, 'read', ncid, posNOTonfile=.true.) call ncd_io( 'ext_cff_mss_dust04', ext_cff_mss_dst4, 'read', ncid, posNOTonfile=.true.) call ncd_pio_closefile(ncid) if (masterproc) then write(iulog,*) 'Successfully read snow optical properties' ! print some diagnostics: write (iulog,*) 'SNICAR: Mie single scatter albedos for direct-beam ice, rds=100um: ', & ss_alb_snw_drc(71,1), ss_alb_snw_drc(71,2), ss_alb_snw_drc(71,3), & ss_alb_snw_drc(71,4), ss_alb_snw_drc(71,5) write (iulog,*) 'SNICAR: Mie single scatter albedos for diffuse ice, rds=100um: ', & ss_alb_snw_dfs(71,1), ss_alb_snw_dfs(71,2), ss_alb_snw_dfs(71,3), & ss_alb_snw_dfs(71,4), ss_alb_snw_dfs(71,5) if (DO_SNO_OC) then write (iulog,*) 'SNICAR: Including OC aerosols from snow radiative transfer calculations' else write (iulog,*) 'SNICAR: Excluding OC aerosols from snow radiative transfer calculations' endif write (iulog,*) 'SNICAR: Mie single scatter albedos for hydrophillic BC: ', & ss_alb_bc1(1), ss_alb_bc1(2), ss_alb_bc1(3), ss_alb_bc1(4), ss_alb_bc1(5) write (iulog,*) 'SNICAR: Mie single scatter albedos for hydrophobic BC: ', & ss_alb_bc2(1), ss_alb_bc2(2), ss_alb_bc2(3), ss_alb_bc2(4), ss_alb_bc2(5) if (DO_SNO_OC) then write (iulog,*) 'SNICAR: Mie single scatter albedos for hydrophillic OC: ', & ss_alb_oc1(1), ss_alb_oc1(2), ss_alb_oc1(3), ss_alb_oc1(4), ss_alb_oc1(5) write (iulog,*) 'SNICAR: Mie single scatter albedos for hydrophobic OC: ', & ss_alb_oc2(1), ss_alb_oc2(2), ss_alb_oc2(3), ss_alb_oc2(4), ss_alb_oc2(5) endif write (iulog,*) 'SNICAR: Mie single scatter albedos for dust species 1: ', & ss_alb_dst1(1), ss_alb_dst1(2), ss_alb_dst1(3), ss_alb_dst1(4), ss_alb_dst1(5) write (iulog,*) 'SNICAR: Mie single scatter albedos for dust species 2: ', & ss_alb_dst2(1), ss_alb_dst2(2), ss_alb_dst2(3), ss_alb_dst2(4), ss_alb_dst2(5) write (iulog,*) 'SNICAR: Mie single scatter albedos for dust species 3: ', & ss_alb_dst3(1), ss_alb_dst3(2), ss_alb_dst3(3), ss_alb_dst3(4), ss_alb_dst3(5) write (iulog,*) 'SNICAR: Mie single scatter albedos for dust species 4: ', & ss_alb_dst4(1), ss_alb_dst4(2), ss_alb_dst4(3), ss_alb_dst4(4), ss_alb_dst4(5) write(iulog,*) end if end subroutine SnowOptics_init subroutine SnowAge_init( ) use CLM_varctl , only : fsnowaging use fileutils , only : getfil use spmdMod , only : masterproc use ncdio_pio , only : file_desc_t, ncd_io, ncd_pio_openfile, ncd_pio_closefile type(file_desc_t) :: ncid ! netCDF file id character(len=256) :: locfn ! local filename character(len= 32) :: subname = 'SnowOptics_init' ! subroutine name integer :: varid ! netCDF id's integer :: ier ! error status ! Open snow aging (effective radius evolution) file: allocate(snowage_tau(idx_rhos_max,idx_Tgrd_max,idx_T_max)) allocate(snowage_kappa(idx_rhos_max,idx_Tgrd_max,idx_T_max)) allocate(snowage_drdt0(idx_rhos_max,idx_Tgrd_max,idx_T_max)) if(masterproc) write(iulog,*) 'Attempting to read snow aging parameters .....' call getfil (fsnowaging, locfn, 0) call ncd_pio_openfile(ncid, locfn, 0) if(masterproc) write(iulog,*) subname,trim(fsnowaging) ! snow aging parameters call ncd_io('tau', snowage_tau, 'read', ncid, posNOTonfile=.true.) call ncd_io('kappa', snowage_kappa, 'read', ncid, posNOTonfile=.true.) call ncd_io('drdsdt0', snowage_drdt0, 'read', ncid, posNOTonfile=.true.) call ncd_pio_closefile(ncid) if (masterproc) then write(iulog,*) 'Successfully read snow aging properties' ! print some diagnostics: write (iulog,*) 'SNICAR: snowage tau for T=263K, dTdz = 100 K/m, rhos = 150 kg/m3: ', snowage_tau(3,11,9) write (iulog,*) 'SNICAR: snowage kappa for T=263K, dTdz = 100 K/m, rhos = 150 kg/m3: ', snowage_kappa(3,11,9) write (iulog,*) 'SNICAR: snowage dr/dt_0 for T=263K, dTdz = 100 K/m, rhos = 150 kg/m3: ', snowage_drdt0(3,11,9) endif end subroutine SnowAge_init end module SNICARMod