Methane Remote Sensing Results in Voluntary Reduction of over One Million Tons CO2e

A direct result of surveys detecting methane emissions using innovative remote-sensing technology

June 9, 2022

As a direct result of surveys detecting methane emissions from oil and gas, waste, and agricultural sites using innovative remote-sensing technology, 44 individual California facilities voluntarily took corrective actions between 2017 and 2021, preventing the equivalent of 1.2 million metric tons of CO2 from escaping into the atmosphere. The results, directly verified by follow-up observations, confirm the important role airborne surveys can play in making methane emissions visible and actionable in fighting climate change.

This unprecedented achievement was made possible by public and private sector partners that took part in California Methane Surveys conducted between 2016 and 2018 with additional flights in 2020 and 2021. Further analysis indicates that the ultimate reductions may increase more than 200% to 2.5 million metric tons CO2e when predicted (but not yet directly verified) emissions are included based on reported operator actions. This is roughly the equivalent of removing over 500,000 gas-powered passenger cars from the road for a year.

“Leaks and hardware malfunctions can generate very high methane emission rates but can be hard to detect and accurately quantify since many are intermittent or occur randomly over large areas. These examples highlight the need for—and impact of—sustained wide-area monitoring to alert operators, regulators, and communities to issues and show that when armed with timely information, many operators take corrective action on their own,” said Riley Duren, Chief Executive Officer of Carbon Mapper—a nonprofit organization focused on locating, quantifying, and mitigating methane and CO2 point-source emissions using observations from air and space. Duren initiated this research program in 2016 while at NASA’s Jet Propulsion Laboratory (JPL) and continued the effort at Carbon Mapper and the University of Arizona with colleagues at JPL and the California Air Resources Board (CARB).

“The simple truth about this super pollutant is that that you can’t stop methane leaks if you don’t know where they’re coming from. This research pilot provides a powerful example for how data generated from remote observations can find leaks and inform actions to quickly stop them,” said Richard W Corey, CARB Executive Officer. “This is an invaluable tool that supports California’s statutory target of reducing methane emissions 40% below 2013 levels by 2030, and the Global Methane Pledge to cut methane 30% compared to 2020 levels by 2030. We need to expand the use of this technology to ensure that we have timely information on leaks, and make sure that sources are fully accountable for quickly mitigating the emissions that adversely impact our climate and air quality.” 

The airborne methane surveys over California, starting in 2016 and initially funded by NASA, CARB, and the California Energy commission, were conducted using advanced imaging spectrometers operated by JPL and Arizona State University. The earliest surveys established a baseline assessment of high-emitting methane sources for the state (point-sources emitting 10 kilograms of methane per hour or more) and included landfills, oil and gas production sites, natural gas infrastructure, dairies, refineries, power plants, and wastewater treatment plants. In 2017, the team began alerting operators at facilities with persistently high emissions. In most cases, the operators confirmed and then repaired methane leaks.

Building on this success, CARB and Carbon Mapper (respectively) funded additional overflights in fall 2020 and 2021, while CARB expanded the notification and voluntary response process to more operators. This resulted in additional methane mitigation actions.

Almost half of the emission abated from these efforts were directly verified using follow up airborne observations that indicated methane emissions reductions were sustained for at least one year. The remaining predicted reductions are based on reported actions that require additional frequent observations over at least a year to confirm their magnitudes and permanence. The monitoring cost of this pilot program translated to approximately $2-4 per mitigated ton of CO2e.

SoCalGas, the country’s largest gas distribution utility headquartered in Los Angeles, is one example of a company that responded proactively to notifications of methane leaks. Airborne observations pinpointed about five low-pressure gas pipeline leaks and a leaking isolation valve at a compressor station that, once notified, the company was able to confirm and remediate these sources. In years since, SoCalGas has continued to build out its emissions intelligence to ensure optimal performance of their equipment and reduce emissions. Other examples include mitigation actions taken by operators of landfills, power plants, and oil fields.

“Collaborations with organizations like Carbon Mapper represent an important part of our emissions reduction efforts. The SoCalGas system has one of the lowest methane emissions rates in the country, and we constantly look for ways to reduce fugitive emissions even further,” said Jawaad Malik, Vice President of Strategy and Sustainability and Chief Sustainability Officer for SoCalGas. “Our investments in more advanced leak detection technologies, including aerial mapping, have allowed us to reduce methane emissions and repair leaks faster, putting us four years ahead of schedule on California’s methane reduction targets.” 

These pilot studies which involved a few weeks of flights each year only scratch the surface of what is possible in California. It also makes clear the benefits to other key jurisdictions globally when methane monitoring becomes more continuous, transparent, and able to pinpoint emissions at the scale necessary to support routine decision-making at individual facilities. This airborne work is the foundation on which the Carbon Mapper Satellite Program was built and demonstrates a fraction of the potential global impact that the coalition hopes to achieve. With a ground-breaking hyperspectral satellite constellation being built in partnership with Planet Labs PBC and NASA JPL, the coalition looks to pinpoint, quantify, and track point-source methane and CO2 emissions and share that data with industry, governments, and private citizens. The launch of the first two demonstration satellites is planned for late 2023.

“Later is too late to act on climate change. Addressing the effects of methane must be a top priority for every government as called for by the Global Methane Pledge, and California is well on its way to achieving a 40% reduction by 2030,” said Governor Newsom. “California is proposing an all-of-the-above approach to reduce pollution and transition away from fossil fuels—everything from launching satellites that will track methane emissions throughout the world, to fixing leaks from idle oil wells. We’re encouraged by these global partnerships to tackle this problem together, for the benefit of all nations.”

Visit the Carbon Mapper data portal for emissions data associated with these mitigation examples and publications for more information about methods and broader findings about California methane emissions.




About Carbon Mapper

Carbon Mapper is a non-profit organization focused on facilitating timely action to mitigate greenhouse gas emissions. Its mission is to fill gaps in the emerging global ecosystem of methane and CO2 monitoring systems by delivering data at facility scale that is precise, timely, and accessible to empower science-based decision making and action. The organization is leading the development of the Carbon Mapper constellation of satellites supported by a public-private partnership composed of Planet, NASA’s Jet Propulsion Lab, the California Air Resources Board, the University of Arizona, Arizona State University, and RMI, with funding from High Tide Foundation, Bloomberg Philanthropies, The Grantham Foundation, and other philanthropic donors. Learn more at and follow us on Twitter @carbonmapper.

About California Air Resources Board

CARB is the lead agency in California for cleaning up the air and fighting climate change to attain and maintain health-based air quality standards. Its mission is to promote and protect public health, welfare, and ecological resources through the effective reduction of air and climate pollutants while recognizing and considering effects on the economy. To learn more visit and follow us on Twitter at @AirResources.


JPL is a federally-funded research and development center managed by Caltech for NASA. Since the start of the Space Age, JPL has developed and launched robotic missions to explore the solar system and beyond. NASA-JPL missions also monitor Earth from land, air and space with a fleet of satellites and airborne and ground-based observation campaigns collecting long-term data records that contribute to understanding and protecting our home planet.

About University of Arizona

The University of Arizona, a land-grant university with two independently accredited medical schools, is one of the nation’s top 50 public universities, according to U.S. News & World Report. Established in 1885, the university is widely recognized as a student-centric university and has been designated as a Hispanic Serving Institution by the U.S. Department of Education. The university ranked in the top 20 in 2020 in research expenditures among all public universities, according to the National Science Foundation, and is a leading Research 1 institution with $761 million in annual research expenditures. The university advances the frontiers of interdisciplinary scholarship and entrepreneurial partnerships as a member of the Association of American Universities, the 66 leading public and private research universities in the U.S. It benefits the state with an estimated economic impact of $4.1 billion annually.

About Arizona State University

Arizona State University’s Global Airborne Observatory (GAO) is owned and operated by the Center for Global Discovery and Conservation Science at Arizona State University. The GAO is made possible by support from private foundations, visionary individuals, and Arizona State University. ASU, ranked No. 1 “Most Innovative School” in the nation by U.S. News & World Report for seven years in succession, has forged the model for a New American University. ASU is a comprehensive public research institution, measured not by whom it excludes, but by whom it includes and how they succeed; advancing research and discovery of public value; and assuming fundamental responsibility for the economic, social, cultural, and overall health of the communities it serves.

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