def func_solv(albedo):
return toa_cor_o3 - sl.alb2rtoa(albedo, t1, t2, r0, ak1, ak2, ratm,
r)
def func_solv(albedo):
return toa_cor_o3 - sl.alb2rtoa(albedo, tau, g, p, amf, am1, am2, r0,
ak1, ak2)
area[D < D_thresh] = np.nan
al[D < D_thresh] = np.nan
r0[D < D_thresh] = np.nan
bal[D < D_thresh] = np.nan
cos_sza[D < D_thresh] = np.nan
cos_vza[D < D_thresh] = np.nan
#D[D<D_thresh] = np.nan
# =========== clean snow ====================================
# for that we calculate the theoretical reflectance at band 1 of a surface with:
# r0 = 1, a (albedo) = 1, ak1 = 1, ak2 = 1
# t1 and t2 are the backscattering fraction
t1, t2, ratm, r, astra, rms = sl.prepare_coef(tau, g, p, cos_sza, cos_vza,
inv_cos_za, gaer, taumol, tauaer)
rs_1 = sl.alb2rtoa(1, t1[0, :, :], t2[0, :, :], np.ones_like(r0),
np.ones_like(ak1), np.ones_like(ak2), ratm[0, :, :],
r[0, :, :])
# we then compare it to the observed toa[0] value
ind_clean = toa_cor_o3[0, :, :] >= rs_1
isnow[ind_clean] = 0
# STEP 4a: clean snow retrieval
# the spherical albedo derivation: alb_sph
def mult_channel(c, A):
tmp = A.T * c
return tmp.T
alb_sph = np.exp(-np.sqrt(1000. * 4. * np.pi *
isnow[D < D_thresh] = 104
for i in range(21):
toa_cor_o3[i, D < D_thresh] = np.nan
area[D < D_thresh] = np.nan
al[D < D_thresh] = np.nan
r0[D < D_thresh] = np.nan
bal[D < D_thresh] = np.nan
am1[D < D_thresh] = np.nan
am2[D < D_thresh] = np.nan
D[D < D_thresh] = np.nan
# =========== clean snow ====================================
# for that we calculate the theoretical reflectance at band 1 of a surface with:
# r0 = 1, a (albedo) = 1, ak1 = 1, ak2 = 1
rs_1 = sl.alb2rtoa(1, tau[0, :, :], g[0, :, :], p[0, :, :], amf, am1, am2, 1,
1, 1)
# we then compare it to the observed toa[0] value
ind_clean = toa_cor_o3[0, :, :] >= rs_1
isnow[ind_clean] = 0
# STEP 4a: clean snow retrieval
alpha = 4. * np.pi * bai / w
absor = g * np.nan
# the spherical albedo derivation: alb_sph
al_clean = al
al_clean[isnow != 0] = np.nan
for i_channel in range(21):
absor[i_channel, :, :] = 1000. * alpha[i_channel] * al_clean
alb_sph[i_channel, :, :] = np.exp(-np.sqrt(absor[i_channel, :, :]))
