Improving the Spectral Fit of NASA's OMI Formaldehyde Operational Product

Abstract:

Formaldehyde (H₂CO) concentrates in the Earth’s troposphere and is produced from both anthropogenic activities and natural sources. It is a hazardous air pollutant with adverse effects on human health. H₂CO reacts quickly in the atmosphere and is a proxy for non-methane volatile organic compounds (NMVOCs) emissions in satellite measurements. This study presents the Ozone Monitoring Instrument (OMI) formaldehyde retrieval developed with the Smithsonian Astrophysical Observatory’s Making Earth System Data Records for Use in Research Environments (MEaSUREs) program’s retrieval algorithm. It aims to improve the current OMI NASA’s operational H₂CO retrieval from a scientific point of view and adapting the retrieval pipeline to work with OMI Collection 4 level 1 radiances. Retrievals will be improved by adopting new cross sections for ozone, water vapor and sulfur dioxide, testing a new solar reference spectrum in the retrieval algorithm, and re-doing windows analysis considering fitting parameter correlations, fitting uncertainties, residuals, expected values and latitudinal biases. Updated Air Mass Factor (AMF) will also be calculated and the result of this study will be compared to the result from the operational retrieval of NASA OMI H₂CO.