OMPS LP Observations of PSC and Ozone Variability During the NH 2019-2020 Winter Season

Abstract:

Seasonal depletion of the stratospheric ozone layer in polar regions during late winter and early spring is strongly influenced by chemical reactions involving chlorine and bromine species that are sequestered on polar stratospheric cloud (PSC) surfaces during polar night, then released through photodissociation of these species when sunlight returns in the spring. The Northern Hemisphere 2019-2020 winter/spring season was exceptional in terms of PSC formation and longevity in the Arctic, as well as subsequent ozone depletion. We present new observations of PSCs from the Ozone Mapping and Profiling Suite (OMPS) Limb Profiler (LP) instrument, flying on the Suomi NPP satellite since 2012. The hyperspectral capabilities of OMPS LP enable cloud detection to occur concurrent with stratospheric ozone measurements from the same instrument. PSCs are identified within the population of clouds normally observed by LP, and an estimate of total PSC area can be calculated. Since LP PSC observations are coincident with ozone profiles retrieved from the same instrument, these PSC results provide a direct indication of the local conditions that lead to ozone depletion. The lower stratospheric ozone changes observed by LP were unprecedented during its 8-year lifetime. Future LP instruments flying on JPSS satellites will continue PSC observations into the 2030s.