SCOAPE 2019: Evaluation and Application of S5P and SNPP Observations for Air Quality Monitoring in the Gulf of Mexico

NASA/Goddard has an Interagency Agreement with the Bureau of Ocean Energy Management (BOEM, Dept. of Interior), to assess the feasibility of using satellite data to measure Air Quality (AQ) over the US continental shelf and adjacent coast. BOEM's objective is to determine whether an anticipated rapid increase in offshore oil and natural gas (ONG) activity over the next several years will lead to increased pollution that significantly affects onshore AQ. There are two deliverables for BOEM: (1) a report that reviews a series of satellite products, e.g., column NO₂ from Aura OMI and S5P TROPOMI; S5P VIIRS for detection of flares. (2) an experiment to collect trace gas measurements (O₃, NO₂, CH₄, CO₂, VOC, CO) and to validate satellite column NO2 over the Gulf of Mexico (GOM). The experiment, designated SCOAPE (Satellite Coastal and Oceanic Atmospheric Pollution Experiment), was conducted in mid-May 2019 with NO₂ instrumentation (Pandora, Ecotech analyzer) at Cocodrie, Louisiana, and with a suite of AQ sensors on the Research Vessel Point Sur sailing off the Louisiana and Mississippi coasts. SCOAPE sampling targets included deepwater oil platforms and regions of highly concentrated smaller operations closer to shore where there is an absence of AQ measurements. We present sampling details of SCOAPE and a summary of NO₂ measurements with emphasis on: (1) evaluations of TROPOMI NO₂ data with ground- and ship-based Pandora columns and (2) relationships between column and in situ NO₂ on land and at sea. TROPOMI and Pandora column NO₂ show good correlations (0.7 or better) in our comparisons. Additional analyses include the application of the SNPP VIIRS flaring product to track ONG activity during SCOAPE.