Replication Data for: Active face emissions: An opportunity for reducing methane emissions in global waste management

Surveys were carried out using repeated on-site, fenceline, and off-site public-road transects and stationary downwind holds, under different wind conditions, to pass through or intercept plumes at varying distances. The measurement vehicle was equipped with a Gill WindSonicM ultrasonic anemometer (wind speed accuracy ~3% and direction ±3°), an RM Young 32500 electronic compass (±2°), a Garmin 18x 5 Hz GPS, and Los Gatos Research analyzers (UGGA or LGR-ICOS Microportable GLA131; CH₄ precision ~1.4 ppb for the Microportable).

Prior to each day’s measurements, analyzers were checked against certified reference gases, the compass was verified using the four cardinal directions, and the inlet-to-analyzer transit time was measured and applied to correct timestamps. Calibration gases were referenced to WMO mole-fraction scales (X2004a for CH₄; X2019 for CO₂). Data were logged on a common, synchronized timebase with standardized QC steps (timestamp sync, GPS correction, wind-vector correction for vehicle motion, instrument-lag correction, and basic completeness checks).