The variable IHAZE selects one of the predefined aerosol model or coupled with OPAC aerosol database, thus defining the aerosol optical properties (i.e., extinction, absorption and scattering) used for the boundary-layer (0-2 km). The available options are shown in the Table below:
Value(s) | Description |
---|---|
0 |
No aerosols/clouds |
1 |
Rural * Default value
|
4 |
Maritime * |
5 |
Urban * |
6 |
Tropospheric *
|
≥ 11 |
User-defined
|
≤ -1 |
Opac
|
* Parameters and refractive indices based on (Shettle et al., 1979).
The relative humidity dependence of the boundary-layer aerosol extinction coefficients is based on the water vapor content of the model atmosphere selected by MODEL and its only applied for Rural, Maritime, Urban, Tropospheric and OPAC aerosol models. The seasonal dependence of their vertical profiles for both the tropospheric (2-10 km) and stratospheric (10-30 km) aerosols is automatically selected through the model atmosphere selected by MODEL.
This variable, therefore, has an impact on the simulation of the absorption-scattering processes caused by suspended particles in the sun-target-sensor optical path.
The amount of suspended particles is specified separately from the Aerosol Optical Thickness (VIS) key input variable.
Shettle, E.P., & Fenn, R.W., (1979), "Models for the Aerosols of the Lower Atmosphere and the Effects of Humidity Variations on Their Optical Properties." Available from Air Force Geophysics Lab. Hanscom Field, Berdford, MA. 01731
Gathman, S.G., (1983), "Optical properties of the marine aerosol as predicted by the Navy Aerosol Model." Optical Engineering, 22(1), 220157.