sail_BDRF {ccrtm}

The SAIL BDRF function

Description

The SAIL BDRF function

Usage

sail_BDRF(w, lai, sumint, tsstoo, rsoil, rdd, tdd, tsd, rsd, tdo, rdo, tss,
  too, rsod)

Arguments

w

goemeric reflectance parameter

lai

leaf area index

sumint

exp int

tsstoo

Bi-directional gap fraction

rsoil

background reflectance

rdd

Bi-hemispherical reflectance over all in & outgoing directions (white-sky albedo).

tdd

Bi-hemispherical transmittance (diffuse transmittance in all directions)

tsd

Directional hemispherical transmittance for solar flux

rsd

Directional hemispherical reflectance for solar flux (diffuse solar angle)

tdo

Directional hemispherical transmittance (diffuse in viewing direction)

rdo

Directional hemispherical reflectance in viewing direction

tss

Direct transmittance of solar flux

too

Direct transmittance in viewing direction

rsod

Multi scattering contribution

Value

spectra matrixwith 4 reflectance factors and canopy transmission for wavelengths 400 to 2500nm:

• [1] = bi-hemispherical reflectance (rddt). White-sky albedo: the reflectance of the canopy under diffuse illumination. The BRDF integrated over all viewing and illumination directions.

• [2] = hemispherical directional reflectance (rsdt). Black-sky albedo: reflectance of a surface under direct light without a diffuse component. It is the integral of the BRDF over all viewing directions.

• [3] = directional hemispherical reflectance (rdot). Diffuse reflectance in the vieweing direction.

• [4] = bi-directional reflectance (rsot). The ratio of reflected radiance in the viewing direction to the incoming radiant flux in the solar direction.

• [5] = Canopy transmission of diffuse light through the canopy (taud).

• [6] = transmission of direct light through the canopy (taus).