A model for the separation of cloud and aerosol in SAGE II occultation data

The Stratospheric Aerosol and Gas Experiment (SAGE) II satellite experiment measures the extinction due to aerosols and thin cloud, at wavelengths of 0.525 and 1.02 μm, down to an altitude of 6 km. The wavelength dependence of the extinction due to aerosols differs from that of the extinction due to cloud and is used as the basis of a model for separating these two components. The model is presented and its validation using airborne lidar data, obtained coincident with SAGE II observations, is described. This comparison shows that smaller SAGE II cloud extinction values correspond to the presence of subvisible cirrus cloud in the lidar record. Examples of aerosol and cloud data products obtained using this model to interpret SAGE II upper tropospheric and lower stratospheric data are also shown.

[1]  Pi-Huan Wang,et al.  Inference of stratospheric aerosol composition and size distribution from SAGE II satellite measurements , 1989 .

[2]  William P. Chu,et al.  Stratospheric aerosol and gas experiment III (SAGE III) , 1993, Defense, Security, and Sensing.

[3]  Michael K. Griffin,et al.  Optical scattering and microphysical properties of subvisual cirrus clouds, and climatic implications , 1989 .

[4]  M. McCormick,et al.  SAGE II aerosol correlative observations: Profile measurements , 1989 .

[5]  William P. Chu,et al.  SAGE II inversion algorithm , 1989 .

[6]  M. McCormick,et al.  SAGE II aerosol data validation based on retrieved aerosol model size distribution from SAGE II aerosol measurements. , 1989, Journal of geophysical research.

[7]  Andrew J. Heymsfield,et al.  A parameterization of the particle size spectrum of ice clouds in terms of the ambient temperature and the ice water content , 1984 .

[8]  M. McCormick,et al.  Global optical climatology of the free tropospheric aerosol from 1.0-μm satellite occultation measurements , 1991 .

[9]  J. Gras.  Southern hemisphere tropospheric aerosol microphysics , 1991 .

[10]  William P. Chu,et al.  Stratospheric aerosol and gas experiment III: aerosol and trace gas measurements for the Earth Observing System , 1991, Defense, Security, and Sensing.

[11]  K. Snetsinger,et al.  SAGE II aerosol validation: selected altitude measurements, including particle micromeasurements. , 1989, Journal of geophysical research.

[12]  E. M. Patterson,et al.  Global measurements of aerosols in remote continental and marine regions: Concentrations, size distributions, and optical properties , 1980 .

[13]  L. E. Mauldin,et al.  Stratospheric Aerosol And Gas Experiment II Instrument: A Functional Description , 1985 .

[14]  M. P. McCormick,et al.  Zonal and geographical distributions of cirrus clouds determined from SAGE data , 1986 .

[15]  G. S. Kent,et al.  Separation of cloud and aerosol in two-wavelength satellite occultation data , 1991 .

[16]  M. McCormick,et al.  Inversion of stratospheric aerosol and gaseous constituents from spacecraft solar extinction data in the 0.38-1.0-microm wavelength region. , 1979, Applied optics.