int getatmvariables(float mus, float muv, float phi, int16 height,
unsigned char *process, float *sphalb, float *rhoray, float *TtotraytH2O,
float *tOG)
{
double m, Ttotrayu, Ttotrayd, tO3, tO2, tH2O;
float psurfratio;
int j, ib;
/*
Values for bands 9-16 below provided by B Murch and C Hu Univ South Florida
IMaRS, obtained from SEADAS.
For the moment I've retained the Jacques values for 1-8 but show the differing
SEADAS values in the commented out line.
*/
const float aH2O[Nbands]={0.000406601 ,0.0015933 , 0,1.78644e-05 ,0.00296457 ,0.000617252 , 0.000996563,0.00222253 ,0.00094005 , 0.000563288, 0, 0, 0, 0, 0, 0 };
const float bH2O[Nbands]={ 0.812659,0.832931 , 1., 0.8677850, 0.806816 , 0.944958 ,0.78812 ,0.791204 ,0.900564 ,0.942907 , 0, 0, 0, 0, 0, 0 };
/*const float aO3[Nbands]={ 0.0711, 0.00313, 0.0104, 0.0930, 0, 0, 0, 0.00244, 0.00383, 0.0225, 0.0663, 0.0836, 0.0485, 0.0395, 0.0119, 0.00263};*/
const float aO3[Nbands]={ 0.0433461, 0.0, 0.0178299 ,0.0853012 , 0, 0, 0, 0.0813531, 0, 0, 0.0663, 0.0836, 0.0485, 0.0395, 0.0119, 0.00263};
/*const float taur0[Nbands] = { 0.0507, 0.0164, 0.1915, 0.0948, 0.0036, 0.0012, 0.0004, 0.3109, 0.2375, 0.1596, 0.1131, 0.0994, 0.0446, 0.0416, 0.0286, 0.0155};*/
const float taur0[Nbands] = { 0.04350, 0.01582, 0.16176, 0.09740,0.00369 ,0.00132 ,0.00033 ,0.05373 ,0.01561 ,0.00129, 0.1131, 0.0994, 0.0446, 0.0416, 0.0286, 0.0155};
float taur[Nbands], trup[Nbands], trdown[Nbands];
static float sphalb0[MAXNUMSPHALBVALUES];
static char first_time = TRUE;
if (first_time) {
sphalb0[0] = 0.0F;
for(j = 1; j < MAXNUMSPHALBVALUES; j++)
sphalb0[j] = csalbr(j * TAUSTEP4SPHALB);
first_time = FALSE;
}
m = 1.0 / mus + 1.0 / muv;
if (m > MAXAIRMASS) return -1;
psurfratio = expf(-height / (float) SCALEHEIGHT);
for (ib = 0; ib < Nbands; ib++)
if (process[ib]) taur[ib] = taur0[ib] * psurfratio;
chand(phi, muv, mus, taur, rhoray, trup, trdown, process);
for (ib = 0; ib < Nbands; ib++) {
if (!process[ib]) continue;
if (taur[ib] / TAUSTEP4SPHALB >= MAXNUMSPHALBVALUES) {
sphalb[ib] = -1.0F;
/* Use sphalb as flag to indicate atm variables are not computed successfully */
continue;
}
sphalb[ib] = sphalb0[(int)(taur[ib] / TAUSTEP4SPHALB + 0.5)];
Ttotrayu = ((2 / 3. + muv) + (2 / 3. - muv) * trup[ib]) / (4 / 3. + taur[ib]);
Ttotrayd = ((2 / 3. + mus) + (2 / 3. - mus) * trdown[ib]) / (4 / 3. + taur[ib]);
tO3 = tO2 = tH2O = 1.0;
if (aO3[ib] != 0) tO3 = exp(-m * UO3 * aO3[ib]);
if (bH2O[ib] != 0) tH2O = exp(-(aH2O[ib]*(pow((m * UH2O),bH2O[ib]))));
/*
t02 = exp(-m * aO2);
*/
TtotraytH2O[ib] = Ttotrayu * Ttotrayd * tH2O;
tOG[ib] = tO3 * tO2;
}
return 0;
}
int update_gridcell_atmos_coefs(int irow,int icol,atmos_t *atmos_coef,Ar_gridcell_t *ar_gridcell, sixs_tables_t *sixs_tables,int **line_ar,Lut_t *lut,int nband, int bkgd_aerosol) {
int ib,ipt,k;
float mus,muv,phi,ratio_spres,tau_ray,aot550;
double coef;
float actual_rho_ray,actual_T_ray_up,actual_T_ray_down,actual_S_r;
float rho_ray_P0,T_ray_up_P0,T_ray_down_P0,S_r_P0;
float lamda[7]={486.,570.,660.,835.,1669.,0.,2207.};
float tau_ray_sealevel[7]={0.16511,0.08614,0.04716,0.01835,0.00113,0.00037}; /* index=5 => band 7 */
ipt=irow*ar_gridcell->nbcols+icol;
mus=cos(ar_gridcell->sun_zen[ipt]*RAD);
muv=cos(ar_gridcell->view_zen[ipt]*RAD);
phi=ar_gridcell->rel_az[ipt];
ratio_spres=ar_gridcell->spres[ipt]/1013.;
/* eric is trying something */
/* if ((irow == 53 )&&(icol == 83))
{
printf("let's see what is going on\n");
}
*/
if (bkgd_aerosol) {
atmos_coef->computed[ipt]=1;
aot550=0.01;
} else {
if (line_ar[0][icol] != lut->aerosol_fill) {
atmos_coef->computed[ipt]=1;
aot550=((float)line_ar[0][icol]/1000.)*pow((550./lamda[0]),-1.);
} else {
/*
atmos_coef->computed[ipt]=0;
*/
atmos_coef->computed[ipt]=1;
aot550=0.01;
}
}
for (k=1;k<SIXS_NB_AOT;k++) {
if (aot550 < sixs_tables->aot[k])
break;
}
k--;
if (k>=(SIXS_NB_AOT-1))
k=SIXS_NB_AOT-2;
coef=(aot550-sixs_tables->aot[k])/(sixs_tables->aot[k+1]-sixs_tables->aot[k]);
/* printf("pressure ratio %d %d %f \n",irow,icol,ratio_spres);*/
for (ib=0;ib < nband; ib++) {
atmos_coef->tgOG[ib][ipt]=sixs_tables->T_g_og[ib];
atmos_coef->tgH2O[ib][ipt]=sixs_tables->T_g_wv[ib];
atmos_coef->td_ra[ib][ipt]=(1.-coef)*sixs_tables->T_ra_down[ib][k]+coef*sixs_tables->T_ra_down[ib][k+1];
atmos_coef->tu_ra[ib][ipt]=(1.-coef)*sixs_tables->T_ra_up[ib][k]+coef*sixs_tables->T_ra_up[ib][k+1];
atmos_coef->rho_mol[ib][ipt]=sixs_tables->rho_r[ib];
atmos_coef->rho_ra[ib][ipt]=(1.-coef)*sixs_tables->rho_ra[ib][k]+coef*sixs_tables->rho_ra[ib][k+1];
atmos_coef->td_da[ib][ipt]=(1.-coef)*sixs_tables->T_a_down[ib][k]+coef*sixs_tables->T_a_down[ib][k+1];
atmos_coef->tu_da[ib][ipt]=(1.-coef)*sixs_tables->T_a_up[ib][k]+coef*sixs_tables->T_a_up[ib][k+1];
atmos_coef->S_ra[ib][ipt]=(1.-coef)*sixs_tables->S_ra[ib][k]+coef*sixs_tables->S_ra[ib][k+1];
/**
compute DEM-based pressure correction for each grid point
**/
tau_ray=tau_ray_sealevel[ib]*ratio_spres;
chand(&phi,&muv,&mus,&tau_ray,&actual_rho_ray);
actual_T_ray_down=((2./3.+mus)+(2./3.-mus)*exp(-tau_ray/mus))/(4./3.+tau_ray); /* downward */
actual_T_ray_up = ((2./3.+muv)+(2./3.-muv)*exp(-tau_ray/muv))/(4./3.+tau_ray); /* upward */
csalbr(&tau_ray,&actual_S_r);
rho_ray_P0=sixs_tables->rho_r[ib];
T_ray_down_P0=sixs_tables->T_r_down[ib];
T_ray_up_P0=sixs_tables->T_r_up[ib];
S_r_P0=sixs_tables->S_r[ib];
atmos_coef->rho_ra[ib][ipt]=actual_rho_ray+(atmos_coef->rho_ra[ib][ipt]-rho_ray_P0); /* will need to correct for uwv/2 */
atmos_coef->td_ra[ib][ipt] *= (actual_T_ray_down/T_ray_down_P0);
atmos_coef->tu_ra[ib][ipt] *= (actual_T_ray_up/T_ray_up_P0);
atmos_coef->S_ra[ib][ipt] = atmos_coef->S_ra[ib][ipt]-S_r_P0+actual_S_r;
atmos_coef->td_r[ib][ipt] = actual_T_ray_down;
atmos_coef->tu_r[ib][ipt]=actual_T_ray_up;
atmos_coef->S_r[ib][ipt]=actual_S_r;
atmos_coef->rho_r[ib][ipt]=actual_rho_ray;
if ( is_ar_check_pixel(icol, irow) ) {
printf( " line_ar[0][%d]=%d, aot550=%.15g, k=%d, coef=%.15g\n",
icol, line_ar[0][icol], aot550, k, coef );
report_atmos_coef( atmos_coef, ib, ipt );
}
}
return 0;
}
