RAMI website

Turbid

RAMI3 phase

This set of experiments was suggested to simulate the radiative transfer regime under conservative scattering conditions for heterogeneous environments.
These scenes - which are structurally identical to those used for the turbid floating spheres test cases in the solar domain - are composed of a large number of non overlapping spherical objects representing the individual plant crowns, located over and only partially covering a horizontal plane standing for the underlying soil surface.

These objects, in turn, contained a 'gas' (to be treated as a turbid medium) of dimension-less particles representing the leaves. These scattering particles were characterized by conservative radiative properties (reflectance=0.5, transmittance=0.5), and the orientation of the normals to the scatterers followed exclusively a uniform distribution function. The radiative properties of the underlying soil were also specified (in this case a simple Lambertian scattering law) with the surface albedo being unity.

The following figures exhibit a graphical representation that approximates the impression that such a scene gives when viewed from the side:

Side scene representation
The figure exhibits a graphical representation that approximates the impression that such a scene gives when viewed from the side.
Top scene representation
The figure exhibits a graphical representation that approximates the impression that such a scene gives when viewed from the top.
zero azimuth line
The zero azimuth line.

The architecture of this scene (HET02) is precisely characterized as follows:

Scene dimensions:

( X × Y × Z)100.0 × 100.0 × 30.0 [m × m × m]
(Xmin, Ymin, Zmin)−50.0, −50.0, 0.0 [m, m, m]
(Xmin, Ymax, Zmin)−50.0, +50.0, 0.0 [m, m, m]
(Xmax, Ymin, Zmin)+50.0, −50.0, 0.0 [m, m, m]
(Xmax, Ymax, Zmin)+50.0, +50.0, 0.0 [m, m, m]
(Xmin, Ymin, Zmax)−50.0, −50.0, 30.0 [m, m, m]
(Xmin, Ymax, Zmax)−50.0, +50.0, 30.0 [m, m, m]
(Xmax, Ymin, Zmax)+50.0, −50.0, 30.0 [m, m, m]
(Xmax, Ymax, Zmax)+50.0, +50.0, 30.0 [m, m, m]
Scatterer shapeDisc of negligible thickness
Scatterer radius0 or close to 0 [m]
LAI of individual sphere5.0
Scatterer normal distributionUniform
Number of spheres15
Fractional scene area coverage of spheres0.471
Sphere radius10.0 [m]
Minimum sphere center height11.0 [m]
Maximum sphere center height19.0 [m]

where the Leaf Area Index (LAI) is the total foliage area within a sphere divided by the cross sectional area of that sphere.

The coordinates (X, Y, Z) of the sphere centers are as follows:

−24.8302; 11.6110; 15.6210−38.3380; −9.06342; 17.6094−31.3562; 32.5297; 14.3051
11.9126; 8.32062; 12.122039.4855; 37.1247; 16.3647−8.30999; −4.39422; 14.4241
12.2769; −25.1402; 12.449232.4756; −26.9023; 16.3684−7.46991; −32.2138; 12.6678
−27.4794; −32.0266; 15.914633.5709; −6.31039; 14.5332−5.24326; 39.8405; 16.8247
18.1699; 35.8223; 11.5683−5.26569; 18.9618; 17.253537.8226; 14.6769; 11.5936

The underlying soil is occupying the entire lower surface of the scene, i.e., the area enclosed between the following coordinates: (−50.0, −50.0, 0.0), (−50.0, +50.0, 0.0), (+50.0, −50.0, 0.0), and (+50.0, +50.0, 0.0), where all values are in meters.

The tables below provide the details required to execute each of the experiments in this category.

The tables below provide the details required to execute each of the experiments in this category. Every table is preceeded by the corresponding experiment identifier that is needed in the naming of the various measurement results files (see file naming and formatting conventions).

brfop

Results for BRF in the cross plane (perpendicular to the principal plane)

brfop_co_sgl

Results for BRF in the cross plane for single-scattered radiation

brfop_mlt

Results for BRF in the cross plane for multiple-scattered (two or more scattering events) radiation

brfop_uc_sgl

Results for BRF in the cross plane for single-scattered radiation collided by the soil

brfpp

Results for BRF in the principal plane (total)

brfpp_co_sgl

Results for BRF in the principal plane for single-scattered radiation

brfpp_mlt

Results for BRF in the principal plane for multiple-scattered (two or more scattering events) radiation

brfpp_uc_sgl

Results for BRF in the principal plane for single-scattered radiation collided by the soil

fabs

Results for Absorption by the canopy (turbid or discrete)

ftran

Results for Total transmission through the medium at the lower boundary level