Airborne Remote Sensing of Methane

Next-generation imaging spectrometers known as methane “plume mappers” have the capability to survey large areas and identify large, localized sources of methane. The California Air Resources Board, has been involved in four research airborne studies in which plume mapping sensors were placed onboard planes. These planes overflew pieces of infrastructure from different methane source sectors, including oil and gas, agriculture, and waste. These studies have shown the following overall results:

Methane plumes can be found across the State and across all methane source sectors
These plumes may make up an important part of the State’s total methane emissions
Mitigation can occur quickly, often times within one week of a plume being observed

While these intermittent studies have yielded important results, they have also demonstrated the need for persistent observations of individual sources of methane throughout the State. These research studies have laid the foundation for the development of the California Satellite Partnership and the Satellite Data Purchase Program that will enable the identification of large methane plumes across the State and the world on a continuous basis, and will aid in the control of these emissions.

First Research Study: The California Methane Survey

The California Methane Survey was a ground-breaking research project conducted from 2016-2018 that aimed to identify and quantify the occurrence of large emission sources of methane using advanced research-grade technologies. Conducted by NASA JPL through funding from CARB, NASA, and the California Energy Commission, this first-of-its-kind statewide survey used a plume mapping imaging camera called Airborne Visible InfraRed Imaging Spectrometer - Next Generation (AVIRIS-NG). The result of this research effort highlighted the need for consistent observations of methane emissions from individual sources. 

A map of areas surveyed during the California Methane Survey
Figure: Areas surveyed during the California Methane Survey

Resources for the California Methane Survey

Second, Third, and Fourth Research Studies: Mitigation Research Studies

During three follow-up studies to the California Methane Survey, CARB partnered with NASA JPL and the University of Arizona (November 2020), and Carbon Mapper (November 2021 and June 2023) to conduct additional airborne campaigns. These campaigns served as a 'dry-run' to prepare data systems and test mitigation strategies for future satellite observations. CARB worked with industry partners (oil and gas, utilities, and landfill operators) to share information on large methane leaks with the operators in near-real-time. The industry partners voluntarily acted to investigate the identified methane plumes, mitigate observed leaks, and report back to CARB on their findings. Results from the 2020-2021 fall campaigns suggest that nearly half of the identified methane can be mitigated. The June 2023 campaign results are still being compiled, but preliminary results further cement these findings.

Areas surveyed during the Mitigation Research Studies. Map includes flights funded by CARB and Carbon Mapper.

California Air Resources Board