SAGE I Aerosol O3 NO2 Binary version 1 (SAGE_I_AEROSOL_O3_NO2_BINARY_V1) is now available.
NASA’s ASDC has released a collection from Stratospheric Aerosol and Gas Experiment I (SAGE I) that includes measurements of aerosol extinction, as well as ozone and nitrogen dioxide concentration profiles, from February 21, 1979 to November 18, 1981.
NASA deployed the Stratospheric Aerosol and Gas Experiment I (SAGE I) instrument into space on the Applications Explorer Mission-B (AEM-B) satellite on February 18, 1979. SAGE I featured four spectral channels (wavelengths of 385, 450, 600, and 1000 nanometers), enabling near-global profiling of aerosol extinction, as well as ozone and nitrogen dioxide concentrations.
To maximize latitudinal coverage for solar occultation observations, NASA positioned the AEM-B satellite in orbit at roughly 600 kilometers altitude with a 56-degree inclination, allowing measurements from 79 degrees South latitude to 79 degrees North. Data collection continued for nearly three years until a power subsystem failure ended the AEM-B satellite's operations.
Operating as a sun photometer, SAGE I measured the attenuation of solar radiation as it passed through Earth's atmosphere during orbital sunrise and sunset events. The SAGE I team integrated these solar radiance measurements with spacecraft positioning data and meteorological information from NOAA, then processed them through numerical inversion techniques to generate vertical profiles of aerosol extinction at 450 and 1000 nanometers. The team also made vertical profiles of ozone and nitrogen dioxide concentrations.
The team validated SAGE I data through comparisons with various independent measurement sources: aerosol data were verified against lidar and dustsonde in situ observations; ozone profiles were validated using balloon-based ECC ozonesonde and rocket measurements; and nitrogen dioxide results were assessed against climatological data.