Towards Multi-Spectral, Multi-Sensor Satellite Retrievals of Air Quality Relevant Gases Using the Reusable Framework for Atmospheric Composition

Abstract:

New satellite constellations, such as TROPOMI onboard the Sentinel-5 Precursor Mission and the CrIS instrument onboard Suomi-NPP, are enabling advances in determining the spatio-temporal distribution of air quality relevant trace gas profiles. Maximizing the benefits from these new measurements requires radiative transfer models that can handle wide spectral ranges in the solar and/or thermal regions of the electromagnetic spectrum and a retrieval framework that allows integration of measurements from multiple sensors.

The Reusable Framework for Atmospheric Composition (ReFRACtor) is an extensible multi-instrument atmospheric composition retrieval framework that supports and facilitates data fusion of radiance measurements from different instruments in the ultraviolet, visible, near- and thermal-infrared. ReFRACtor is designed to retrieve trace gas vertical profile concentrations in a consistent manner across spectral regions, by combining a fast and accurate principal component analysis (PCA)-based radiative transfer model with a sophisticated non-linear optimal estimation solver. ReFRACtor enables application of the same code base to different sensors using a consistent retrieval methodology, thus facilitating comparison of retrievals of the same species across sensors. The ultimate goal is to extend current single-instrument retrieval capabilities to joint multi-spectral, multi-species retrievals such as from AIRS/OMI and CrIS/TROPOMI.

We present simulations showing the capability of ReFRACtor to simulate pan-spectral measurements at arbitrary spectral resolution and show first multi-spectral, multi-sensor results from AIRS/OMI and CrIS/TROPOMI.

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