Using OMPS-LP color ratio to extract stratospheric aerosol particle radius and estimate its uncertainty

The Ozone Mapping Profiler Suite Limb Profiler (OMPS-LP) uses limb scattering to measure the aerosol extinction coefficient at multiple wavelengths. We use the color ratio from the OMPS-LP extinction coefficient to derive the median radius of stratospheric aerosols and provide an estimate of its total uncertainty. The total uncertainty combines three primary sources: extinction measurement errors, uncertainty related to assumptions about aerosol size distribution width, and uncertainty due to the scattering phase function used by the OMPS-LP retrieval algorithm. Comparisons with in situ balloon measurements suggest that log-normal aerosol size distribution width values of 1.6 and 1.5 are appropriate for background conditions and the post-Raikoke (2019) eruption, respectively. Our results show favorable agreement with other satellite instruments on retrieved particle size. We show how aerosol particle radii evolve following the 2019 Raikoke and 2022 Hunga eruptions and quantify the uncertainty in particle sizes.