Quantifying Methane Point Sources in High-Resolution Satellite Imagery

Abstract:

Obtaining accurate rates of emissions from point sources is challenging because the stochastic eddy-scale features captured by a satellite snapshot often dominate the morphology of plumes that emerge from point sources. To explore a new procedure of quantifying methane emissions from point sources using satellite remote sensing, we ran simulations of emissions from point sources in exemplary oil and gas extraction areas, using the Weather Research and Forecasting Model coupled with Chemistry (WRF-Chem) on a large-eddy simulation (LES) mode with Realistic Topography and driving Meteorology (RTM). We estimated plume sizes and emission fluxes at the sources using integrated mass enhancement and cross-sectional flux techniques. To measure the constraints of the proposed framework, we assessed the minimum resampling times for targeted confidence intervals of methane emission estimates and examined the smallest distance between two different point sources that can be resolved and quantified. Using the proposed framework, we repeated the investigations with complex sources such as line and area sources. We determined the information that LES with RTM provides in addition to idealized LES, which ignore real topography and meteorological data but were used in multiple studies in the past. We can learn if knowledge of emissions is improved using these high-resolution models, whether simple empirical plume models can be parameterized to capture the results of high-resolution approaches, and how to adapt LES with RTM applications to an operational scale of satellite-based emission estimations.