Figure 1
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Atmospheric methane is a potent greenhouse gas and an important contributor to air quality. Future instruments on orbiting satellites can help improve our understanding of important methane emission sources. NASA is currently conducting a California Methane Survey to demonstrate such technologies on aircraft using NASA's next-generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) instrument. Funded jointly by the California Air Resources Board, California Energy Commission and NASA, the California Methane Survey is determining the locations and magnitudes of the largest methane emission sources in the state, including those associated with landfills, refineries, dairies, wastewater treatment plants, oil and gas fields, and natural gas infrastructure.

These three images show concentrations of methane in the gas plume relative to background air, overlaid on AVIRIS-NG true-color land surface images. The aircraft was flying at an altitude of about 6,500 feet (2,000 meters) above ground level and the AVIRIS-NG image pixels are about 6.5 feet (2 meters) across. The plume shape varies with changing wind speed and direction. The plumes are caused by a leaking low-pressure natural gas pipeline under a street. The JPL team immediately notified the gas company who confirmed and repaired the leak. The upper right image was acquired by AVIRIS-NG on Sept. 25, 2016, confirming that after the pipeline repair, no methane was detected at that location. Figure 1 shows a higher-resolution close-up (source: Google Earth) view indicating the likely plume origin, which JPL provided to the gas company.

For more information on AVIRIS-NG, visit https://avirisng.jpl.nasa.gov/.