|
3-
VERSIONS and REFERENCES |
|
5-SCALE was first built using a combination of 4-Scale 3.2 and LIBERTY 1.1a. |
|
|
|
|
|
The core of 4-Scale (version 1) is described in: |
|
[1]J. M. Chen and S.G. Leblanc. A Four-Scale Bidirectional Reflectance Model
Based on Canopy Architecture. (changes and typos) |
|
|
|
and was improved (version 2) in: |
|
[2]S. G. Leblanc, P. Bicheron , J. M. Chen, M. Leroy and J. Cihlar, Investigation of directional reflectance in
boreal forests using an improved 4-Scale model and airborne POLDER Data.(changes
and typos) |
|
|
|
5-scale (version 1) is described in: |
|
[15]S. G. Leblanc and J. M. Chen A Windows Graphic User Interface (GUI) for
the |
|
|
|
other papers featuring 4-Scale: |
|
|
|
[3] S. G. Leblanc, J. M. Chen and J. Cihlar, Directionality of NDVI in Boreal
Forest: A Model Simulation of Measurements (changes
and typos) |
|
[4] J.M Chen, S. G. Leblanc, J. Cihlar, P. Bicheron, M. Leroy, D. Deering, and T. Eck. Studies
of BRDF in conifer and deciduous boreal forests using the 4-Scale model and airborne
POLDER and ground-based PARABOLA measurements. |
|
|
|
Introduction of the multiple scattering scheme in: |
|
|
|
[5] S.G. Leblanc and J.M. Chen Applications of the
4-Scale Radiative-Transfer Model in Proceeding IGARSS '98, Seattle |
|
[6] J.M. Chen and S. G. Leblanc A Geometrical
multiple scattering scheme to be used in IEEE TGARS 2001 vol. 39, pp. 1061-1071.
|
|
|
|
4-Scale was used to understand and correct BRDF signature of boreal forest in |
|
[7] J.M. Chen, S.G. Leblanc, J. R. Miller, J. Freemantle, S. E. Loechel, C. L. Walthall, K. A. Innanen, and H. P. White Compact Airborne Spectrographic Imager
(CASI) used for Second BOREAS special issue of
the |
|
[13] L. Brown, J. M. Chen, S. G. Leblanc, and J. Cihlar |
|
|
|
4-Scale 1.0 was associated with paper [1] and 4-Scale 2.0 -2.5 include the improvements described in [2]. |
|
The double-canopy version from [2]. is not included in the code, but can be re-optained by using the one-canopy version twice. Contact us if you need to use 4-Scale in the double-canopy mode. |
|
The Figures in paper [4] were made with 4-Scale 2.6. |
|
The Figures in paper [5] were made with 4-Scale 3.0 |
|
The Figures in paper [6] were made with 5-Scale 1.2. |
Modifications:
|
5-SCALE 1.3.3 A few small changes since
1.2.5, the major change is related the foliage phase function. 5-SCALE 1.2.5 |
|
Solved a non-conservation of energy in the multiple scattering scheme. ->(R+T)/2 |
|
5-SCALE 1.2.4 |
|
Added protection for inputs of reflectivity and transmitance |
|
5-SCALE 1.2.3 |
|
Changed the hyperspectral mode. It nows computes a principal plane at different degree interval (VZA from 0 to 80°) and displays teh resukts in countour-like plots. Build 05W: Added Normalization factors to nadir for red and nir bands in PLANE mode. |
|
5-SCALE 1.2.2 |
|
Added Log plots to hyperspectral mode and LIBERTY. Later builds (June 2000) also have more HDS plots choices. |
|
5-SCALE 1.2.1 |
|
Mean distance between
crowns computed using: Er = Lt/Wt |
|
5-SCALE 1.2 |
|
The major differences between 5-Scale 1.0 and 1.2 are found in the multiple scattering scheme, especially the parts that include foliage transmittance. Plus a few improvements to the interface were also made. |
|
5-SCALE 1.0 |
|
Major improvement of the
interface, especially the plotting area. Introduction of LIBERTY as part of
the software. |
|
4-SCALE 3.3 |
|
This is the 4-Scale code of 5-Scale 1.2. Used mainly in the name file convention we use. |
|
4-SCALE 3.2 |
|
Improved interface and multiple-scattering scheme (note that the changes to the multiple scattering between version 3.0 and 3.2 and to 5-Scale 1.2 (4-Scale 3.3) are minimal, but important in some specific cases). |
|
4-SCALE 3.1 |
|
Q1tot and Q2tot have been re-coded to actually do what they were supposed to do (also in 2.5.1). |
|
A new repulsion function that gives a smoother response in some extreme cases (also in 2.5.1). |
|
Changes in the multiple scattering scheme. |
|
The nadir view has been improved to include special cases when the shadows and the crowns are not independent statistically. |
|
The mean distance between trees is now computed using the gap size distribution (also in 2.5.1). |
|
A correction to Ls and Hs has been made because the hotspot on the crown was not sensitive enough to LAI density changes inside crowns. |
|
4-SCALE 3.0 |
|
Introduction of a multiple scattering scheme |
|
Paper [5] had a short description of the method used to computed the scattering effect in the canopy. |
|
Paper [6] has all the new changes. |
|
4-SCALE 2.6 |
|
This version has a more realistic computation of the light going through a leave that takes into account the transmittance of the foliage. It does not have the changes made in 2.5.1. The changes made here have been overwritten in version 3.0 and more. |
|
4-SCALE 2.5.1 |
|
This version was produced while version 3.0 was developed and includes (1) the new repulsion function Fr; (2) the new Q1tot and Q2tot; and (3) the new mean distance between trees calculated with the gap size distribution. |
|
4-SCALE 2.5 |
|
Some code lines have been rewritten, C-structures have been incorporated to simplify the subroutine calls (as a preparation for adding the MS Windows interface with MS Visual C++). |
|
There are 2 main structures: in_p and out_p. in_p contains the input parameters, out_p contains the output calculations. |
|
|
|
NOTE 1: The parameters.c file structure, which is used to read the input file, has changed between v. 2.5 and 2.5.1 and up.The old input files do not work with the latest version of the model. 5-Scale input files are more or less compatible with that of previous versions. Contact us if you have a problem with this. |
|
NOTE 2: A version of the model (2.7) has never been officially distributed but it has a different way of dealing with the multiple scattering effect based on the distance between trees. |
|
NOTE 3: Some README files distributed with version 2.5 mentionned a version 3.1. This version was renamed 2.6 since the final changes were not worth a new version number. |
|
Other References |
|
|
|
[8] Chen J.M. and T.A.
Black, 1991. “Measuring Leaf Area Index of Plant Canopies with Branch
Architecture.” |
|
[9]Chen J.M. and T.A. Black, 1992. “Defining leaf area index for nonflat leaves” Plant Cell Environ., vol. 15, pp. 421-429. |
|
[10] Li, X. and A.H.
Strahler, 1992. “Geometric-Optical Bidirectional Reflectance
Modeling of the Discrete Crown Vegetation Canopy: Effect of Crown Shape and
Mutual Shadowing.”, IEEE Trans. Geosci. Rem. Sens., vol. 30, pp.
276-292. |
|
[11] Neyman, J., 1939. “On a New Class of ‘Contagious’ Distribution Applicable in Entomology and Bacteriology”, Annals of Mathematical Statistics, vol. 10, pp. 35-57. |
|
[12] Chen J.M. “Canopy Architecture and
Remote Sensing of the fraction of Photosynthetically Active radiation
Absorbed by Boreal Conifer Forests” IEEE Trans. Geosci. Rem.
Sens., vol. 34, pp. 1353-1368. |
|
[14] Dawson, T.P.,
Curran, P.J. and Plummer, S.E. (1998), "LIBERTY - Modelling the effects of
leaf biochemistry on reflectance spectra, Remote Sensing of
Environment," |
|
[16] Chen, J.M., R. Lacaze, S.G. Leblanc, J.-L., Roujean, and J. Liu (1999) “POLDER BRDF and photosynthesis: an angular signature useful for ecological applications," Abstract to 2nd international workshop on multiangular measurements and models (poster presentation in letter paper format available on request), Ispra, Italy, 15-17 September 1999. |
|
[17] Black, T.A., J.M. Chen, X. Lee, and R. Sagar (1991) “Characteristics of shortwave and longwave irradiance under a Douglas-fir forest stand" Canadian J. Forest Res, Vol. 21, pp. 1020-1028 |
|
[18] R. Lacaze, J. M. Chen, J. L. Roujean, and S. G. Leblanc (2001) |
|
S. G.
Leblanc and J. M. Chen |
|
S. G. Leblanc, J. M.
Chen, H. P. White, J. Cihlar, R. Lacaze, J.-L. Roujean, and R. Latifovic. (2001) |