From Site-Level Detections to Monthly and Annual National Totals: Multiyear VIIRS Nightfire Estimates of Global Gas Flaring

This study advances global gas-flaring monitoring from a sequence of annual inventories to a monthly, source-resolved, multi-satellite record of upstream gas flaring from March 2012 through December 2025, using VIIRS Nightfire observations from SNPP, NOAA-20, and NOAA-21. The analysis integrates a persistent multiyear flare catalog, a calibration derived from controlled flare tests relating radiant heat to gas flow rate, and an aggregation framework that separates clear non-detections from cloud-affected, sunlit, or otherwise invalid observations. The framework yields consistent monthly and annual estimates from individual flare sites to country and global scales. Global upstream flaring reached 164.5 BCM in 2025, the third consecutive annual increase, and was highly concentrated: 4.3% of active sites accounted for 80% of the global volume. Summed monthly estimates are internally consistent with direct annual estimates (median ratio 98.1%) while revealing seasonal patterns and short-term changes hidden in annual inventories. Global estimates from the three VIIRS instruments agree within 1–4%, and comparisons with regulatory records for Texas (Permian and Eagle Ford) and New Mexico, regions with reliable reporting but atypically small and intermittent flares, show strong temporal agreement (monthly r = 0.85–0.91) and recovery of 69–96% of reported volumes. Comparisons with legacy estimates further show that differences among flaring products reflect combined changes in source coverage, calibration, satellite sampling, and aggregation rather than a uniform rescaling of annual totals. Cloud-covered overpasses must be excluded rather than counted as non-detections, which would lower global volumes by 27–30%, and the catalog must be refreshed every 6–12 months to remain representative.