Quantifying Point‐Source Methane Enhancements From MethaneSAT: Detection Performance and Plume Estimation

Abstract Methane is a potent greenhouse gas with large emissions often arising from localized point sources in industrial facilities. MethaneSAT, launched in 2024, observes the 1,598–1,683 nm band with sub–nanometer resolution and 100 m × 400 m footprints, thereby bridging the gap between regional mapping and facility–scale monitoring and improving the detection of methane point sources from the energy and waste sectors. We introduce a Bias–Corrected Matched Filter (BCMF) with covariance exclusion and a statistical correction for linearization bias, mitigating the low bias observed in conventional matched–filter retrievals. Simulations and retrievals under MethaneSAT observing conditions show that BCMF mitigates the low bias observed in conventional matched–filter retrievals with algorithmic noise constrained to ≤40 ppb (1σ). Across multiple emission scenarios, 17 plumes were detected and cross–section emission flux estimates agree with MethaneSAT proxy products ( r = 0.965, MAPE = 20.3%). These results demonstrate BCMF as a fast robust approach for quantifying methane emissions with next–generation high–resolution satellite sensors.