Aerosol Optical Depth as interpolated from GEOS5 for the aer_opt2ang case
4-km domain, forecast hour 24
aer_opt2ang Case uses:
GEOS 3-hourly aerosol optical depth
GEOS 3-hourly aerosol angstrom exponent
fixed single scattering albedo = 0.85
fixed aerosol asymmetry parameter = 0.9