California Air Resources Board

Methane is an important greenhouse gas (GHG) that is responsible for more than 25 percent of current global warming. Methane has a relatively short lifetime in the atmosphere (about a decade), meaning that emission reductions in the near term will slow the pace of global temperature rise. 

Previous research studies supported by the California Air Resources Board (CARB) have used a novel class of instruments referred to as ‘methane plume mappers’ onboard planes to identify individual plumes of methane in California. Images of the plumes identified during these flight campaigns can be seen in CARB’s Methane Source Finder tool. However, airplanes equipped with these technologies cannot cover large spatial areas with the frequency needed to support programs for large-scale methane mitigation. 

 
Methane plumes mapped aboard aircraft during the California Methane Survey 

Commercial satellite companies are in the early stages of developing and deploying satellites equipped with similarly-capable methane plume mapping instruments. These satellite systems may enable frequent observation of large portions of California, thus supporting regulatory mitigation programs and helping California reach its climate targets. To that end, the California State Budget Act of 2022 allocated $100 million for the purchase of methane plume data from a commercial satellite company. The California State Budget Act of 2022 also recognized that commercial satellites may collect valuable measurements of other important environmental indicators. This money will be awarded through a competitive request for proposal (RFP) process, which is currently ongoing. In addition, $5 million was allocated to develop capacity in communities to use this data.  

CARB is committed to reducing greenhouse gas emissions, with successful regulatory programs targeting methane and other greenhouse gases and will continue to explore how best to use this new information to reduce emissions even further. CARB will continue to work with other jurisdictions to successfully reduce methane emissions through policy and new data sources such as satellite-based observations.