Validation of in situ and remote sensing-derived methane refinery emissions in a complex wind environment and chemical implications

Air pollution emissions from ports are major sources of contaminant exposures to downwind communities. Elevated pollutant concentrations relate port activities and nearby heavy industries including refining. Methane (CH4) in the 66 Refinery plume, located west Los Angeles Port, provided a real-world validation opportunity for situ-derived comparison with imaging spectroscopy-derived emissions. Airborne remote sensing data were acquired by airborne thermal infrared Mako spectrometer, while contemporaneous situ meteorology trace gas measurements air samples collected using ground based mobile system, SISTER™ (Standard Instrumentation Suite: Truck Enabled Response). SISTER measures 13 gases, meteorology, aerosol size distributions, vertical profiles at up highway speeds. Real-time visualization is used target sample collection. & 19 June 2020 additional 16 July 2020. In CH4 derived two series inversion plume models different numbers plumes reference The informed spatial data, whereas uninformed did not. survey also oil wells found significantly elevated alkanes through undecane aromatics refinery well compared air. Remote 69 g s−1 (2.18 Gg yr−1), within 20% 87 (2.73 yr−1) 10% four-plume 80 (2.51 yr−1). On an annualized basis, this estimated US refining Derived robust – agreeing 10–20% various models; however, partitioning between was very poor because neglecting wind veering caused mis-assignment. Monte Carlo simulation emission uncertainties 12–13% 24–25% when much lower, 0.25 yr−1. This study emphasized importance fine-scale structure winds respect characterizing sub-facility (kilometer) scale, showing estimation facility scale wide range models. Wind on kilometer smaller scales plays key role understanding fate