Tomographic Retrievals of Stratospheric Ozone with the Ozone Mapping and Profiler Suite Limb Profiler

Abstract

Measurements of limb scattered sunlight have been successfully used to obtain vertically resolved profiles of trace species in the stratosphere and upper troposphere for decades. A common simplifying assumption made in inverting limb scatter measurements is that the atmosphere is horizontally homogenous, which may not be valid in regions of large horizontal gradients such as on the edge of the polar vortex. Here we introduce a new radiative transfer model, SASKTRAN-HR, which can solve the radiative transfer equation in two- and three-dimensional atmospheres. A newly developed technique to approximate the Jacobian matrix for two-dimensional atmospheres is also presented.

SASKTRAN-HR is then used to perform the first tomographic retrieval of ozone from limb scattered sunlight using measurements from the Ozone Mapping and Profiler Suite (OMPS-LP). The tomographic retrieval is shown to remove biases which are present in traditional one-dimensional retrievals that assume horizontal homogeneity. The two-dimensional retrieval agrees favorably with measurements from the Microwave Limb Sounder to within approximately 5%. The retrieval was applied to the full six years of measurements from OMPS-LP to create a publicly available dataset. The dataset has been included in several merged stratospheric ozone composites which are used in the World Meteorogical Association's 2018 ozone assessment.