def run(N,
chloro,
caroten,
brown,
EWT,
LMA,
Ant,
LAI,
hot_spot,
solar_zenith,
solar_azimuth,
view_zenith,
view_azimuth,
LIDF,
skyl=0.2,
soilType=DEFAULT_SOIL):
''' Runs Prospect5 4SAIL model to estimate canopy directional reflectance factor.
Parameters
----------
N : float
Leaf structural parameter.
chloro : float
chlorophyll a+b content (mug cm-2).
caroten : float
carotenoids content (mug cm-2).
brown : float
brown pigments concentration (unitless).
EWT : float
equivalent water thickness (g cm-2 or cm).
LMA : float
dry matter content (g cm-2).
LAI : float
Leaf Area Index.
hot_spot : float
Hotspot parameter.
solar_zenith : float
Sun Zenith Angle (degrees).
solar_azimuth : float
Sun Azimuth Angle (degrees).
view_zenith : float
View(sensor) Zenith Angle (degrees).
view_azimuth : float
View(sensor) Zenith Angle (degrees).
LIDF : float or tuple(float,float)
Leaf Inclination Distribution Function parameter.
* if float, mean leaf angle for the Cambpell Spherical LIDF.
* if tuple, (a,b) parameters of the Verhoef's bimodal LIDF |LIDF[0]| + |LIDF[1]|<=1.
skyl : float, optional
Fraction of diffuse shortwave radiation, default=0.2.
soilType : str, optional
filename of the soil type, defautl use inceptisol soil type,
see SoilSpectralLibrary folder.
Returns
-------
wl : array_like
wavelenghts.
rho_canopy : array_like
canopy reflectance factors.
References
----------
.. [Feret08] Feret et al. (2008), PROSPECT-4 and 5: Advances in the Leaf Optical
Properties Model Separating Photosynthetic Pigments, Remote Sensing of
Environment.
.. [Verhoef2007] Verhoef, W.; Jia, Li; Qing Xiao; Su, Z., (2007) Unified Optical-Thermal
Four-Stream Radiative Transfer Theory for Homogeneous Vegetation Canopies,
IEEE Transactions on Geoscience and Remote Sensing, vol.45, no.6, pp.1808-1822,
http://dx.doi.org/10.1109/TGRS.2007.895844.
'''
# Read the soil reflectance
rsoil = np.genfromtxt(os.path.join(SOIL_FOLDER, soilType))
#wl_soil=rsoil[:,0]
rsoil = np.array(rsoil[:, 1])
# Calculate the lidf
if type(LIDF) == tuple or type(LIDF) == list:
if len(LIDF) != 2:
print(
"ERROR, Verhoef's bimodal LIDF distribution must have two elements (LIDFa, LIDFb)"
)
return None, None
elif LIDF[0] + LIDF[1] > 1:
print(
"ERROR, |LIDFa| + |LIDFb| > 1 in Verhoef's bimodal LIDF distribution"
)
else:
lidf = FourSAIL.CalcLIDF_Verhoef(LIDF[0], LIDF[1])
else:
lidf = FourSAIL.CalcLIDF_Campbell(LIDF)
# PROSPECT5 for leaf bihemispherical reflectance and transmittance
wl, rho_leaf, tau_leaf = ProspectD.ProspectD(N, chloro, caroten, brown,
EWT, LMA, Ant)
# Get the relative sun-view azimth angle
psi = abs(solar_azimuth - view_azimuth)
# 4SAIL for canopy reflectance and transmittance factors
[
tss, too, tsstoo, rdd, tdd, rsd, tsd, rdo, tdo, rso, rsos, rsod, rddt,
rsdt, rdot, rsodt, rsost, rsot, gammasdf, gammasdb, gammaso
] = FourSAIL.FourSAIL(LAI, hot_spot, lidf, solar_zenith, view_zenith, psi,
rho_leaf, tau_leaf, rsoil)
rho_canopy = rdot * skyl + rsot * (1 - skyl)
return wl, rho_canopy
def run_TIR(emisVeg,
emisSoil,
T_Veg,
T_Soil,
LAI,
hot_spot,
solar_zenith,
solar_azimuth,
view_zenith,
view_azimuth,
LIDF,
T_VegSunlit=None,
T_SoilSunlit=None,
T_atm=0):
''' Estimates the broadband at-sensor thermal radiance using 4SAIL model.
Parameters
----------
emisVeg : float
Leaf hemispherical emissivity.
emisSoil : float
Soil hemispherical emissivity.
T_Veg : float
Leaf temperature (Kelvin).
T_Soil : float
Soil temperature (Kelvin).
LAI : float
Leaf Area Index.
hot_spot : float
Hotspot parameter.
solar_zenith : float
Sun Zenith Angle (degrees).
solar_azimuth : float
Sun Azimuth Angle (degrees).
view_zenith : float
View(sensor) Zenith Angle (degrees).
view_azimuth : float
View(sensor) Zenith Angle (degrees).
LIDF : float or tuple(float,float)
Leaf Inclination Distribution Function parameter.
* if float, mean leaf angle for the Cambpell Spherical LIDF.
* if tuple, (a,b) parameters of the Verhoef's bimodal LIDF |LIDF[0]| + |LIDF[1]|<=1.
T_VegSunlit : float, optional
Sunlit leaf temperature accounting for the thermal hotspot effect,
default T_VegSunlit=T_Veg.
T_SoilSunlit : float, optional
Sunlit soil temperature accounting for the thermal hotspot effect
default T_SoilSunlit=T_Soil.
T_atm : float, optional
Apparent sky brightness temperature (Kelvin),
default T_atm =0K (no downwellig radiance).
Returns
-------
Lw : float
At sensor broadband radiance (W m-2).
TB_obs : float
At sensor brightness temperature (Kelvin).
emiss : float
Surface directional emissivity.
References
----------
.. [Verhoef2007] Verhoef, W.; Jia, Li; Qing Xiao; Su, Z., (2007) Unified Optical-Thermal
Four-Stream Radiative Transfer Theory for Homogeneous Vegetation Canopies,
IEEE Transactions on Geoscience and Remote Sensing, vol.45, no.6, pp.1808-1822,
http://dx.doi.org/10.1109/TGRS.2007.895844.
'''
# Apply Kirchoff's law to get the soil and leaf bihemispherical reflectances
rsoil = 1 - emisSoil
rho_leaf = 1 - emisVeg
tau_leaf = 0
# Calculate the lidf,
if type(LIDF) == tuple or type(LIDF) == list:
if len(LIDF) != 2:
print(
"ERROR, Verhoef's bimodal LIDF distribution must have two elements (LIDFa, LIDFb)"
)
return None, None
elif LIDF[0] + LIDF[1] > 1:
print(
"ERROR, |LIDFa| + |LIDFb| > 1 in Verhoef's bimodal LIDF distribution"
)
else:
lidf = FourSAIL.CalcLIDF_Verhoef(LIDF[0], LIDF[1])
else:
lidf = FourSAIL.CalcLIDF_Campbell(LIDF)
# Get the relative sun-view azimth angle
psi = abs(solar_azimuth - view_azimuth)
# 4SAIL for canopy reflectance and transmittance factors
[
tss, too, tsstoo, rdd, tdd, rsd, tsd, rdo, tdo, rso, rsos, rsod, rddt,
rsdt, rdot, rsodt, rsost, rsot, gammasdf, gammasdb, gammaso
] = FourSAIL.FourSAIL(LAI, hot_spot, lidf, solar_zenith, view_zenith, psi,
rho_leaf, tau_leaf, rsoil)
tso = tss * too + tss * (tdo + rsoil * rdd * too) / (1. - rsoil * rdd)
gammad = 1 - rdd - tdd
gammao = 1 - rdo - tdo - too
ttot = (too + tdo) / (1. - rsoil * rdd)
gammaot = gammao + ttot * rsoil * gammad
gammasot = gammaso + ttot * rsoil * gammasdf
aeev = gammaot
aees = ttot * emisSoil
# Get the different canopy broadband emssion components
Hvc = CalcStephanBoltzmann(T_Veg)
Hgc = CalcStephanBoltzmann(T_Soil)
Hsky = CalcStephanBoltzmann(T_atm)
if T_VegSunlit: # Accout for different suntlit shaded temperatures
Hvh = CalcStephanBoltzmann(T_VegSunlit)
else:
Hvh = Hvc
if T_SoilSunlit: # Accout for different suntlit shaded temperatures
Hgh = CalcStephanBoltzmann(T_SoilSunlit)
else:
Hgh = Hgc
# Calculate the blackbody emission temperature
Lw = (rdot * Hsky +
(aeev * Hvc + gammasot * emisVeg *
(Hvh - Hvc) + aees * Hgc + tso * emisSoil * (Hgh - Hgc))) / np.pi
TB_obs = (np.pi * Lw / SB)**(0.25)
# Estimate the apparent surface directional emissivity
emiss = 1 - rdot
return Lw, TB_obs, emiss