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06:27
Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer
Published on: May 29, 2019
Stratospheric Aerosol and Gas Experiment III cloud data product
G S Kent1, K H Sage, C R Trepte
1Science and Technology Corporation, Hampton, Virginia, USA. g.s.kent@larc.nasa.gov
Applied Optics
|February 24, 2007
Summary
The Stratospheric Aerosol and Gas Experiment (SAGE) III instrument provides new data to separate cloud and aerosol effects. This advanced algorithm enhances atmospheric profiling for climate studies.
Area of Science:
- Atmospheric Science
- Remote Sensing
- Aerosol and Cloud Physics
Background:
- The Stratospheric Aerosol and Gas Experiment (SAGE) III is a satellite instrument measuring atmospheric extinction.
- Previous SAGE II data analysis demonstrated wavelength-dependent extinction can differentiate cloud and aerosol effects.
- Global studies of tropospheric cloud and aerosol have extensively utilized SAGE II data.
Purpose of the Study:
- To describe the aerosol-cloud separation algorithm developed for SAGE III data.
- To ensure continuity with existing SAGE II cloud data by examining algorithm performance.
- To present an example application of the algorithm to SAGE III tropospheric data.
Main Methods:
- Utilized extinction data from SAGE III at 525, 1020, and 1550 nm.
- Developed an algorithm to separate cloud and aerosol effects based on multi-wavelength extinction.
- Compared the performance of the SAGE III algorithm with the established SAGE II algorithm.
Main Results:
- The SAGE III algorithm successfully separates cloud and aerosol effects using multi-wavelength extinction.
- Vertical profiles of cloud presence are generated as a standard SAGE III data product.
- Data are available from March 2002 onward, covering altitudes from 6.0 to 30.0 km with 0.5 km resolution.
Conclusions:
- The new SAGE III algorithm provides a reliable method for aerosol-cloud separation.
- This advancement maintains continuity with SAGE II data, enabling long-term climate trend analysis.
- The algorithm's application to tropospheric data demonstrates its utility in atmospheric research.
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