Solar Radiation
Function Overview
The Solar Radiation tool is used to calculate solar radiation for a specific time period, outputting direct, diffuse, and total solar radiation values.
Usage
Click on Terrain > Incident Solar Radiation.
Parameter Settings
- Input DEM File: The input DEM file. For information on generating a DEM, see DEM Generation.
- Water Vapour Pressure: Describes the extent of absorption of solar radiation.
- Link Turbidity Coefficient: The atmospheric turbidity coefficient, describing the extent to which colloidal particles obstruct light transmission. Higher values generally indicate more severe air pollution.
- Solar Constant: The amount of solar radiation received per unit area per second at the top of the atmosphere, perpendicular to the solar rays, at an average distance (D=1.496e8km) from the sun.
- Use Local SVF: Whether to use the sky view factor for the local slope.
- Unit: The unit of radiation values in the output file.
- Shadow: Options for shadow tracking:
- slim: Tracks shadows at grid nodes (faster but may produce artifacts).
- fat: Tracks shadows for the entire grid.
- none: Ignores shadow effects.
- Location: Describes the latitude of the area.
- Latitude: Used when the location is set to a fixed latitude.
- Time Period: Sets the time period for the calculation; options include moment, day, range of days.
- Start Day: The start time of the time period, valid when the time period option is set to range of days.
- End Day: The end time of the time period, valid when the time period option is set to range of days.
- Day: The specific date to be calculated, valid when the time period option is set to day.
- Moment: The specific moment to be calculated, valid when the time period option is set to moment.
- Hour Interval (Hours): The hourly interval used for calculating solar radiation on a daily scale, valid when the time period options are day and range of days.
- Day Interval (Days): The daily interval used for calculating solar radiation over a period of time, valid when the time period option is range of days.
- Atmospheric Effects: Describes the atmospheric influence model, including atmospheric height, water content, dust, and atmospheric transmittance:
- Height of Atmosphere and Vapour Pressure
- Air Pressure, Water and Dust Content
- Lumped Atmospheric Transmittance
- Hofierka and Suri
- Height of Atmosphere: The height of the atmosphere, default value is 12000 meters.
- Barometric Pressure: The atmospheric pressure, default value is 1013 mbar.
- Water Content: Describes the impact of atmospheric water content; the vertical atmospheric water content (cm) ranges from 1.5 to 1.7.
- Dust: Describes the impact of dust.
- Lumped Atmospheric Transmittance: Describes the impact of atmospheric transmittance.
- Output Path: The path for the output files, including direct, diffuse, and total solar radiation TIF files.