MISR UAE2 Aerosol Versioning

MISR-retrieved aerosol optical depths are "Stage-2 Validated," whereas the MISR aerosol microphysical properties are "Beta." Uncertainty envelopes for the aerosol optical depths are given in Kahn et al., 2005a, in press.

The "Beta" designation means particle microphysical property validation is in progress, uncertainty envelopes on particle size distribution, shape, and single-scattering albedo are currently being determined, and further algorithm upgrades significantly affecting the retrieved values of particle microphysical properties are expected. MISR-related UAE-2 campaign activities are part of the validation process, so two versions of the MISR aerosol products are included in this collection to aid in the validation effort.

• Aerosol File Version F07_0015 has better overall particle properties. The aerosol climatology used in this version of the algorithm contains 24 mixtures of nine components, described in detail in Kahn et al., 2005a.

• Aerosol File Version F08_0016 has improved cloud screening procedure resulting in better aerosol optical depth. The aerosol climatology used in this version of the algorithm contains 74 mixtures of eight components. Component microphyscial properties for this version are given in the file MISR_AM1_ACP_APOP_F05_0014.hdf; mixtures are defined in MISR_AM1_ACP_MIXTURE_F05_0019.hdf [see MISR Aerosol Climatology Product].

The F08_0016 climatology aims at addressing some F07_0015 issues raised in Kahn et al., 2005a, and references therein. The changes include:

1. additional spherical pollution and biomass burning analogs having lower single-scattering albedo than Version 15,
2. improved mineral dust optical models (Kalashnikova et al., 2005, JGR, in press),
3. refined calibration, affecting low optical depth retrievals over ocean (Kahn et al., JAS 2005b, in press; Diner et al., SPIE, 2004), and
4. a richer selection of multi-modal particle mixtures.

Further details are provided in the MISR Aerosol Product Quality Statement.

Kahn, R., B. Gaitley, J. Martonchik, D. Diner, K. Crean, and B. Holben, 2005a, MISR global aerosol optical depth validation based on two years of coincident AERONET observations, J. Geophys. Res., doi:jd004706R, in press.