SAGE III on Метеор-3М (SAGE III/M3M) was a third generation, satellite-borne instrument and a crucial element in NASA’s Earth Observing System (EOS). The instrument was launched on the Russian Метеор-3М spacecraft in December 2001.

The SAGE III mission enhanced our understanding of natural and human-derived atmospheric processes by providing accurate measurements of the vertical structure of aerosols, ozone, water vapor, and other important trace gasses in the upper troposphere and stratosphere. Human-derived changes in climate and ozone threaten the health of our planet. They also threaten global economic development and the use of new technologies like high-speed aircraft. By understanding the effect of human activities on the atmosphere, national and international leaders can make informed policy that mitigates or prepares for future climate change.

SAGE III Instrument on Метеор-3М satellite.

The SAGE III instrument is designed similar to the SAGE I and SAGE II instruments with the exception of using an advanced detector package consisting of a two dimensional CCD array detector plus a near-IR photodiode. The new detector design enhances the measurement capability to provide atmospheric spectral coverage from 280 nm to 1040 nm, with a spectral resolution of about 1.2 nm, plus a channel at 1550 nm for separating aerosols and clouds, and for measuring larger aerosols.

The SAGE III instrument consists of three subsystems. The first subsystem is the scan head that consists of the scan mirror mounted on an azimuth drive that can rotate over 360o. The scan mirror scans in elevation so that it can point to the Earth’s limb when the instrument is in orbit. The second subsystem is the imaging optics consisting of a telescope and azimuth target acquisition detectors. The telescope is an f/4 Dall-Kirkham configuration with a one-half arc minute vertical by five arc-minute horizontal slit in the focal plane that serves as the science aperture and as the entrance slit to the grating spectrometer. The whole telescope assembly including the scan mirror can rotate together in azimuth to eliminate the problem of image rotation during azimuth rotation. The third subsystem of the SAGE III sensor is the spectrometer detector package. The spectrometer consists of a holographic grating in a Rowland configuration operating in both zeroth and first orders. The first order dispersion is imaged on the 800 x 10 element CCD, which is back-side thinned to enhance UV response. The zeroth order reflection from the grating is used with a photodiode together with a spectral bandpass filter centered at 1550 nm.

Spatial / Temporal Coverage

  • Spatial Coverage: 50-80N to 30-50S
  • Spatial Resolution: .5km
  • Temporal Coverage: 05/07/2002 – 12/31/2005
  • Temporal Resolution: Solar and Lunar Events

Data Products

  • Ozone (solar and lunar)
  • Aerosol Extinction Profiles
  • Nitrogen Dioxide (solar and lunar)
  • Water Vapor
  • Nitrogen Trioxide


SAGE III 1022-nm aerosol extinction from 1 June 2002 to 8 February 2003.


1.Chiou, E.W., W.P. Chu, and L.W. Thomason, Optimization of SAGE III Spectral Channels for Water Vapor Retrieval, Presented at 9th Conference on Satellite Meteorology and Oceanography, Paris, France, May 25-29, 1998

2.Chiou, E.W., W.P. Chu, and L.W. Thomason, Simulation Studies for the Retrieval of Water Vapor Profiles from the SAGE III Experiment, Presented at 10th Symposium on Meteorological Observations and Instrumentation, Phoenix, Arizona, January 11-16, 1998

3.Cunnold, D., M. McCormick , SAGE III: Algorithm Theoretical Basis Documents for Transmission Level 1B Products, Revised March 26, 2002, EOS Project Science Office, GSFC, 2002

4. IPCC, 1996: Climate Change 1995: The IPCC Second Assessment Report, Cambridge University Press, in press, 1996

5. Pitts, M.C., W.P. Chu, and L.W.Thomason, Remote sensing of temperature by the Stratospheric Aerosol and Gas Experiment III, presented at the International Radiation Symposium, Fairbanks, Alaska, August 1996

6. Pitts, M.C., L.W. Thomason, and W.P. Chu, Satellite remote sensing of temperature and pressure by the Stratospheric Aerosol and Gas Experiment III, Presented at the 9th Conference on Satellite Meteorology and Oceanography, Paris, France, May 1998

7. Thomason, L. W., W. P. Chu, C. R. Trepte, The Stratospheric Aerosol and Gas Experiment, Presented at 9th Conference on Satellite Meteorology and Oceanography, Paris, France, May 25-29, 1998

8.Thomason, L. W. and G. Taha, SAGE III Aerosol Extinction Measurements: Initial Results, Geophysical Research Letters, accepted April 2003

9. Wang, P.-H., and A.D. Risley, SAGE III Mesospheric Ozone Retrieval, Presented at AGU 1998 Fall Meeting, San Francisco, California, December 6-10, 1998

10.Wofsy, S., H. Michelsen, M. McCormick, SAGE III: Algorithm Theoretical Basis Documents for Cloud Data Products, Revised March 26, 2002, EOS Project Science Office, GSFC, 2002 

SAGE III Метеор-3М Science Team Members:

M. Patrick McCormick, Hampton University (Previously NASA Langley Research Center)

Charlotte Brogniez, Laboratoire d’Optique Atmosphérique, Université des Sciences et de Technologies de Lille

Andre A. Chernikov, Space Research Institute of Russia’s Academy of Science

William P. Chu, NASA Langley Research Center

Derek M. Cunnold, Massachusetts Institute of Technology

John DeLuisi, NOAA

Patrick A. Durkee

N.P. Elansky

Benjamin M. Herman, University of Arizona

P.V. Hobbs

Geoff S. Kent

Jennifer le Noble, Universite de Lille, France

A.J. Miller

V.A. Mohnen

V. Ramaswamy

David H. Rind, Goddard Institute for Space Studies

Phillip B. Russell, SRI International Science

V.K. Saxena

Eric P. Shettle

Larry W. Thomason, NASA Langley Research Center

Charles Trepte, NASA Langley Research Center

G. Vali

Steven C. Wofky

Joseph M. Zawodny, NASA Langley Research Center

SAGE III Метеор-3М mission was terminated on March 6, 2006, because of a power supply system failure resulting in loss of communication with the satellite. The Метеор-3М satellite is still in orbit today.


Richard Rawls with SAGE III Метеор-3М.