Speaker
Description
The Stratospheric Aerosol and Gas Experiment (SAGE) III instrument was deployed on the International Space Station (ISS) in early March 2017 and began routine measurements in June 2017. SAGE III retrieves profiles of temperature and pressure from multi-spectral measurements of the oxygen A-band absorption feature centered near 762 nm. The A-band is located in a favorable spectral region where molecular oxygen is the dominant absorber with only minor contributions from ozone absorption, Rayleigh scattering, and aerosol extinction. Since the vertical distribution of molecular oxygen is well known, variations in the measured A-band spectra reveal information about the temperature and pressure structure of the atmosphere. Temperature/pressure products from the predecessor SAGE III METEOR/3M mission were of limited science value due to instrument issues. The SAGE III/ISS oxygen A-band spectra are of higher fidelity than those from the METEOR/3M instrument and the initial temperature/pressure products are in reasonable agreement with MERRA-2 (Modern-Era Retrospective analyses for Research and Applications, Version 2) data. Additional refinements to wavelength registration and forward model parameters have improved the overall quality of the products. In this paper, we will present an overview of the temperature/pressure retrieval approach, results of the forward model studies, and an assessment of the quality of the temperature and pressure research products through comparisons with correlative measurements.
