Satellite Observations of Air Quality Along the Louisiana Coast During 2019 SCOAPE

Abstract

NASA/Goddard has an Interagency Agreement with the Bureau of Ocean Energy Management (BOEM, Dept. of Interior), to assess the usefulness of satellite data for monitoring Air Quality (AQ) along the US coast and the Outer Continental Shelf (OCS). BOEM’s objective is to ensure that OCS oil and natural gas (ONG) activity does not significantly affect onshore AQ of any state. The goals of the Satellite Coastal and Oceanic Atmospheric Pollution Experiment (SCOAPE) project were two-part: (1) a report to BOEM that reviews satellite products and their uses in coastal environments like the Gulf of Mexico (GOM); and (2) an experiment to collect trace gas measurements (O₃, NO₂, CH₄, CO₂, VOCs, CO) along the Louisiana coast for baseline AQ observations and to evaluate satellite column NO₂. We present highlights from the report on the satellite observations over the GOM including the application of the SNPP VIIRS flaring product to track ONG activity during SCOAPE. Comparisons of column NO₂ from Aura OMI and S5P TROPOMI with Pandora instruments over Cocodrie, Louisiana (coastal site) and the Research Vessel Point Sur (open water) indicate generally larger column NO₂ values over the continent than the GOM. TROPOMI and Pandora show good correlations (0.7 or better) in our comparisons with sensitivity to changes in onshore (cleaner air) and offshore (more-polluted air) flows. Once-daily satellite views of ONG operations in the GOM are difficult to capture pollution plumes from individual platforms, but the more-frequent Pandora observations during SCOAPE suggest potential for hourly monitoring with upcoming geostationary missions (ie. TEMPO).