| Tool Name | Potential Incoming Solar Radiation |
| Tool ID | 2 |
| Library ID | ta_lighting |
| Version | 1.0 |
| Author(s) | O.Conrad (c) 2010 |
Böhner, J., Antonić, O. (2009): Land Surface Parameters Specific to Topo-Climatology. In: Hengl, T. & Reuter, H.I. [Eds.]: Geomorphometry - Concepts, Software, Applications.
Hofierka, J., Šúri, M. (2002): The solar radiation model for Open source GIS: implementation and applications. International GRASS users conference in Trento, Italy, September 2002. ResearchGate
Oke, T.R. (1988): Boundary Layer Climates. London, Taylor & Francis.
Wilson, J.P., Gallant, J.C. (2000): Secondary topographic attributes. In: Wilson, J.P., Gallant, J.C. [Eds.]: Terrain analysis: Principles and applications. New York, John Wiley & Sons, Inc., 87-131. ResearchGate
| Name | Type | Identifier | Description | Constraints |
|---|---|---|---|---|
| Input | ||||
| Elevation | grid, input | GRD_DEM | ||
| Sky View Factor | grid, input, optional | GRD_SVF | ||
| Water Vapour Pressure [mbar] | grid, input, optional | GRD_VAPOUR | ||
| Linke Turbidity Coefficient | grid, input, optional | GRD_LINKE | ||
| Output | ||||
| Direct Insolation | grid, output | GRD_DIRECT | ||
| Diffuse Insolation | grid, output | GRD_DIFFUS | ||
| Total Insolation | grid, output, optional | GRD_TOTAL | ||
| Direct to Diffuse Ratio | grid, output, optional | GRD_RATIO | ||
| Compare to Flat Terrain | grid, output, optional | GRD_FLAT | ||
| Duration of Insolation | grid, output, optional | GRD_DURATION | ||
| Sunrise | grid, output, optional | GRD_SUNRISE | ||
| Sunset | grid, output, optional | GRD_SUNSET | ||
| Options | ||||
| Default | floating point number | GRD_VAPOUR_DEFAULT | default value if no grid has been selected | Minimum: 0.000000 Default: 10.000000 |
| Default | floating point number | GRD_LINKE_DEFAULT | default value if no grid has been selected | Minimum: 0.000000 Default: 3.000000 |
| Solar Constant [W/m²] | floating point number | SOLARCONST | Minimum: 0.000000 Default: 1361.000000 | |
| Local Sky View Factor | boolean | LOCALSVF | Use sky view factor based on local slope (after Oke 1988), if no sky viev factor grid is given. | Default: 1 |
| Units | choice | UNITS | Units for output radiation values. | Available Choices: [0] kWh/m² [1] kJ/m² [2] J/cm² Default: 0 |
| Shadow | choice | SHADOW | Choose 'slim' to trace grid node's shadow, 'fat' to trace the whole cell's shadow, or ignore shadowing effects. The first is slightly faster but might show some artifacts. | Available Choices: [0] slim [1] fat [2] none Default: 1 |
| Location | choice | LOCATION | Available Choices: [0] constant latitude [1] calculate from grid system Default: 0 | |
| Latitude | degree | LATITUDE | Minimum: -90.000000 Maximum: 90.000000 Default: 53.000000 | |
| Time Period | choice | PERIOD | Momentum output will be in units of power [W/m²], time span will be in units of energy, either [kWh/m²], [kJ/m²], or [J/cm²]. | Available Choices: [0] moment [1] day [2] range of days Default: 1 |
| Day | date | DAY | Default: 2026-07-17 | |
| Last Day | date | DAY_STOP | Default: 2026-07-17 | |
| Resolution [d] | integer number | DAYS_STEP | Time step size for a range of days calculation given in days. | Minimum: 1 Default: 5 |
| Moment [h] | floating point number | MOMENT | Minimum: 0.000000 Maximum: 24.000000 Default: 12.000000 | |
| Time Span [h] | value range | HOUR_RANGE | Time span used for the calculation of daily radiation sums. | |
| Resolution [h] | floating point number | HOUR_STEP | Time step size for a day's calculation given in hours. | Minimum: 0.000000 Maximum: 24.000000 Default: 0.500000 |
| Atmospheric Effects | choice | METHOD | Available Choices: [0] Height of Atmosphere and Vapour Pressure [1] Air Pressure, Water and Dust Content [2] Lumped Atmospheric Transmittance [3] Hofierka and Šúri Default: 2 | |
| Height of Atmosphere [m] | floating point number | ATMOSPHERE | Minimum: 0.000000 Default: 12000.000000 | |
| Barometric Pressure [mbar] | floating point number | PRESSURE | Minimum: 0.000000 Default: 1013.000000 | |
| Water Content [cm] | floating point number | WATER | Water content of a vertical slice of atmosphere in cm: 1.5 to 1.7, average=1.68 | Minimum: 0.000000 Default: 1.680000 |
| Dust [ppm] | floating point number | DUST | Dust factor: 100 ppm (standard) | Minimum: 0.000000 Default: 100.000000 |
| Lumped Atmospheric Transmittance [Percent] | floating point number | LUMPED | The transmittance of the atmosphere, usually between 60 and 80 percent. | Minimum: 0.000000 Maximum: 100.000000 Default: 70.000000 |