Comparisons of Stratospheric Ozone Measurements from SAGE III-ISS and OMPS-LP

Ozone is an integral part of Earth’s atmosphere, especially in the stratosphere where it protects human life from the sun’s harmful ultraviolet radiation. However, ozone found in the lower troposphere is harmful to human health and the environment. Measuring and monitoring ozone is an important part in understanding its impact on climate and its interactions with other atmospheric constituents. Two instruments that measure ozone are the Stratospheric Aerosol and Gas Experiment III on the International Space Station (SAGE III-ISS), and the Ozone Mapping and Profiler Suite Limb Profiler (OMPS-LP), which is onboard the Suomi-NPP satellite. SAGE III-ISS is an occultation instrument that was launched in February of 2017 and has been taking measurements of ozone since June 2017. OMPS-LP measures limb scattered radiances over visible and ultraviolet wavelengths, and has been taking global measurements of ozone profiles since January 2012. OMPS-LP is planned to be a part of the JPSS series of satellites starting with JPSS-02, and continuing with every new JPSS satellite launched afterwards. With SAGE III-ISS being recently launched, and with OMPS scheduled to be on several satellites in the future, it is important to compare the results of the two instruments to examine how well they agree with one another. This study examined each SAGE III-ISS ozone profile for solar occultation measurements up to 55.5 km, finding the closest OMPS-LP profile to it, by distance, within the same calendar day. Percent differences were calculated and plotted for the comparison profiles. Seasonal comparisons have also been made, along with seasonal zonal averages in varying latitude bin sizes. Initial results have shown the instruments tend to compare well. Some profiles show less than 10% difference from below 20km to above 50km, while many other profiles stay within 20% difference for that range. The seasonal comparisons for layers up to 55.5 km had correlation values of 93% or higher for each of the 4 seasons studied to date.