12.5 Practice 11
12.5.1 Objectives
• to calculate solar radiative characteristics for models of the clear and (or) cloudy
atmosphere;
• to study dependences of irradiances and radiative divergence on optical
parameters and solar zenith angle;
• to compare with values obtained for cloudy atmosphere with asymptotic method,
or clear atmosphere – by single scattering approximation and by Monte-Carlo
approach.
12.5.2 Sequential Steps of the Exercise Implementation
The following radiative characteristics are proposed to calculate for the set of
values of solar zenith angle, optical thickness, single scattering albedo, phase
function parameter, and surface albedo:
1. the reflected and transmitted irradiances. It is noted in the resulting file as “refl”
and “trans”
2. the radiative divergence (div),
3. the rate of diffuse radiation in the transmitted irradiance (dif/transm)
4. the ratio of reflected to transmitted irradiance (refl/transm)
5. the direct irradiance to vertical surface (vertDirect)
6. The overall irradiance (diffused þ direct) to vertical surface (vertSum)
Calculation is accomplished with the compute program “edding.exe” that is
compiled in Borland 4 Cþþ. After the program running the writing is output to
the screen: “Program calculates radiative characteristics and diffusive part with
D-Eddington”
The program “EDDING.exe” proposes the following dialog when questions are
output at the screen sequentially.
1. Input number of wavelength (group tau-lam-g-A)
– It is recommended to input the number of calculation variants;
2. Input number of solar incident angles
– It is recommended to input the number of solar angles;
3. Input wavelengths
– It is possible just numerating: 1,2,3. . . or input values of the wavelength. This
parameter does not participate in calculation;
12.5 Practice 11
125
12.5.1 Objectives
• to calculate solar radiative characteristics for models of the clear and (or) cloudy
atmosphere;
• to study dependences of irradiances and radiative divergence on optical
parameters and solar zenith angle;
• to compare with values obtained for cloudy atmosphere with asymptotic method,
or clear atmosphere – by single scattering approximation and by Monte-Carlo
approach.
12.5.2 Sequential Steps of the Exercise Implementation
The following radiative characteristics are proposed to calculate for the set of
values of solar zenith angle, optical thickness, single scattering albedo, phase
function parameter, and surface albedo:
1. the reflected and transmitted irradiances. It is noted in the resulting file as “refl”
and “trans”
2. the radiative divergence (div),
3. the rate of diffuse radiation in the transmitted irradiance (dif/transm)
4. the ratio of reflected to transmitted irradiance (refl/transm)
5. the direct irradiance to vertical surface (vertDirect)
6. The overall irradiance (diffused þ direct) to vertical surface (vertSum)
Calculation is accomplished with the compute program “edding.exe” that is
compiled in Borland 4 Cþþ. After the program running the writing is output to
the screen: “Program calculates radiative characteristics and diffusive part with
D-Eddington”
The program “EDDING.exe” proposes the following dialog when questions are
output at the screen sequentially.
1. Input number of wavelength (group tau-lam-g-A)
– It is recommended to input the number of calculation variants;
2. Input number of solar incident angles
– It is recommended to input the number of solar angles;
3. Input wavelengths
– It is possible just numerating: 1,2,3. . . or input values of the wavelength. This
parameter does not participate in calculation;
12.5 Practice 11
125