AERTYPE

OPAC aerosol type

Attributes

integer | discrete | dynamic | unit-less | basic

Description

The variable AERTYPE selects one of the predefined or user-defined OPAC aerosol model, 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

-1

Continental (clean)

-2

Continental (average)

-3

Continental (polluted)

-4

Urban

-5

Desert

-6

Maritime (clean)

-7

Maritime (polluted)

-8

Maritime (tropical)

-9

Arctic

-10

Antartic

≤ -11

User-defined

Further information about these aerosol parameters and refractive indices can be found in (Hess et al., 1998) and (Koepke et al., 2015).

The relative humidity dependence of the boundary-layer aerosol extinction coefficients is based on the water vapor content of the model atmosphere (e.g., MODEL in MODTRAN5). 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 (e.g., MODEL in MODTRAN5).

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 in MODTRAN5 and AOT in 6SV) key input variable.

References