RAMI2 phase
This set of experiments was suggested to simulate the radiative transfer regime in the red and near infra-red spectral bands for heterogeneous environmental scenes 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 specified radiative properties (reflectance, transmittance), 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). The particular values selected for these input variables represented classical plant canopy conditions.
The following figures exhibit a graphical representation of such a scene, from the side
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 shape | Disc of negligible thickness |
Scatterer radius | 0 or close to 0 [m] |
LAI of individual sphere | 5.0 |
Scatterer normal distribution | Uniform |
Number of spheres | 15 |
Fractional scene area coverage of spheres | 0.471 |
Sphere radius | 10.0 [m] |
Minimum sphere center height | 11.0 [m] |
Maximum sphere center height | 19.0 [m] |
where the Leaf Area Index (LAI) is calculated as follows:
LAI = (# of leaves × one-sided area of single leaf) ⁄ ( π × square of the radius of 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; 12.1220 | 39.4855; 37.1247; 16.3647 | −8.30999; −4.39422; 14.4241 |
12.2769; −25.1402; 12.4492 | 32.4756; −26.9023; 16.3684 | −7.46991; −32.2138; 12.6678 |
−27.4794; −32.0266; 15.9146 | 33.5709; −6.31039; 14.5332 | −5.24326; 39.8405; 16.8247 |
18.1699; 35.8223; 11.5683 | −5.26569; 18.9618; 17.2535 | 37.8226; 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