Module Sky View Factor
Calculation of visible sky, sky view factor (SVF) and related parameters.
References:
Boehner, J., Antonic, O. (2009): 'Land-surface parameters specific to topo-climatology'. in: Hengl, T., Reuter, H. (Eds.): 'Geomorphometry - Concepts, Software, Applications'. Developments in Soil Science, Volume 33, p.195-226, Elsevier
Hantzschel, J., Goldberg, V., Bernhofer, C. (2005): 'GIS-based regionalisation of radiation, temperature and coupling measures in complex terrain for low mountain ranges'. Meteorological Applications, V.12:01, p.33-42, doi:10.1017/S1350482705001489
Oke, T.R. (2000): 'Boundary Layer Climates'. Taylor & Francis, New York. 435pp.
- Author: O.Conrad (c) 2008
- Specification: grid
- Menu: Terrain Analysis|Lighting
Parameters
| Name | Type | Identifier | Description | Constraints |
Input | Elevation | Grid (input) | DEM | - | - |
Output | Visible Sky | Grid (output) | VISIBLE | The unobstructed hemisphere given as percentage. | - |
Sky View Factor | Grid (output) | SVF | - | - |
Sky View Factor (Simplified) (*) | Grid (optional output) | SIMPLE | - | - |
Terrain View Factor (*) | Grid (optional output) | TERRAIN | - | - |
View Distance (*) | Grid (optional output) | DISTANCE | - | - |
Options | Maximum Search Radius | Floating point | RADIUS | This value is ignored if set to zero. | Minimum: 0.000000 Default: 10000.000000 |
Method | Choice | METHOD | - | Available Choices: [0] multi scale [1] sectors Default: 1 |
Multi Scale Factor | Floating point | DLEVEL | - | Minimum: 1.250000 Default: 3.000000 |
Number of Sectors | Integer | NDIRS | - | Minimum: 3 Default: 8 |
(*) optional |
Command-line
Usage: saga_cmd ta_lighting 3 -DEM <str> [-VISIBLE <str>] [-SVF <str>] [-SIMPLE <str>] [-TERRAIN <str>] [-DISTANCE <str>] [-RADIUS <str>] [-METHOD <str>] [-DLEVEL <str>] [-NDIRS <num>]
-DEM:<str> Elevation
Grid (input)
-VISIBLE:<str> Visible Sky
Grid (output)
-SVF:<str> Sky View Factor
Grid (output)
-SIMPLE:<str> Sky View Factor (Simplified)
Grid (optional output)
-TERRAIN:<str> Terrain View Factor
Grid (optional output)
-DISTANCE:<str> View Distance
Grid (optional output)
-RADIUS:<str> Maximum Search Radius
Floating point
Minimum: 0.000000
Default: 10000.000000
-METHOD:<str> Method
Choice
Available Choices:
[0] multi scale
[1] sectors
Default: 1
-DLEVEL:<str> Multi Scale Factor
Floating point
Minimum: 1.250000
Default: 3.000000
-NDIRS:<num> Number of Sectors
Integer
Minimum: 3
Default: 8