Specifying thermal flux settings

Thermal fluxes are computed based on reference conditions. Some default values are used as reference conditions; for example, air temperature defaults to 20 degrees Celsius at the average elevation. When a constant elevation is used throughout the scene and no DEM is provided, only the air temperature value is used to generate the energy balance components. When a DEM is provided, the air temperature, water vapor partial pressure, and temperature gradients at a reference elevation level must be specified. When a DEM is not provided, the air temperature must be defined at the average elevation value defined in the Illumination Conditions panel.

To specify the thermal flux settings:

  1. Specify the Reference Conditions:
    • In the Elevation Reference field, enter the elevation at which the air temperature applies, in meters.
    • In the Air Temperature field, enter the reference temperature, in degrees Celsius.
    • In the Water Vapor Partial Pressure field, enter the water vapor pressure, at the same elevation, in mbar.
  2. Specify the Air Temperature Gradient, in degrees Celsius for each 100 m of elevation.
  3. Click OK to close the Thermal Flux window and return to the Surface Temperature workflow.
Parent topic: Specifying surface temperature parameters

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