Wofsy also participated in a nationwide study supported by EDF that had researchers across the country measuring methane concentrations near oil and gas facilities. The work, published in the journal Science in 2018, showed that when it came to methane, federal regulators didn’t really know what they were talking about. The amount of emissions found in the study was about 60 percent higher than EPA estimates. That’s enough that the warming caused by the excess methane, over 20 years, is roughly equal to that produced by burning natural gas for heating and cooking each year.

Wofsy became involved in MethaneSAT in 2015, when he got a call from a friend at EDF. The nonprofit wanted to expand its exploration of methane emissions to cover the globe and was considering using a satellite. It wanted Wofsy’s thoughts on the best way to do that and a cost estimate. Wofsy reached out to Kelly Chance, a senior physicist at the Center for Astrophysics | Harvard & Smithsonian, and together they produced a report that put the price tag at tens of millions of dollars.

“We brought that back to EDF, and we assumed that that was the end of it,” Wofsy said. “But they went ahead and raised enough in private philanthropy to fund this thing.”

Wofsy signed on to oversee the mission’s science aspects. He brought with him Chance and other scientists from the Smithsonian Astrophysical Observatory, the Smithsonian arm of the CfA’s Harvard & Smithsonian partnership. Among them was Xiong Liu, a CfA research scientist who became the SAO’s MethaneSAT lead. Liu and those working with him are seeking ways to determine methane abundances from the data, a crucial initial step before sources can be identified.

MethaneSAT’s main scientific instrument is a spectrometer, which breaks white light into a spectrum that bears the telltale fingerprints of molecules in the air through which the light passes. Harvard and SAO scientists provided specifications for the instrument, which was built by contractor Ball Aerospace. The instrument is currently being installed in the spacecraft that will carry it to orbit, Liu said. The satellite’s launch is planned for January 2024 from Cape Canaveral aboard a Falcon 9 rocket from SpaceX, whose founder and chief executive is billionaire Elon Musk.

The power of information

The MethaneSAT project has an ambitious policy goal: reduce global methane emissions from oil and gas facilities by 45 percent by 2025 and 70 percent by 2030. If achieved, it would have a similar impact on the climate over 20 years as closing one-third of the world’s coal plants, EDF said.

“What’s exciting about the MethaneSAT mission is it’s not simply collecting data, we’re putting data into action,” Liu said. “I think that’s the fastest way to slow down global warming. It’s exciting to be part of this project.”

While several satellites, both in orbit and in planning, are designed to detect methane, Wofsy said MethaneSAT will do so at a higher resolution than any other. It will allow researchers to determine methane concentrations, trace them to their sources, and track changes over time.

EDF plans to make the data publicly available — in near real time — to researchers, lobbyists, regulators, and others. In fact, Harvard’s Salata Institute for Climate and Sustainability recently awarded a grant to a multidisciplinary project, headed by the Harvard Kennedy School’s Robert Stavins, that involves 17 faculty members from six Harvard Schools and seeks to leverage publicly available data on methane — including from MethaneSAT — to affect policies and cut emissions.

“We used to think about climate change as something for the distant future — the year 2100 or 2050. But now, as a result of events that have been taking place with the climate, whether it’s floods in Pakistan or fires in California, people have begun to give attention to climate change now,” said Stavins, the A.J. Meyer Professor of Energy and Economic Development, director of the Harvard Environmental Economics Program, and founder of the Harvard Project on Climate Agreements. “And when you do that, the relative importance of methane increases tremendously.”

The satellite will cover about 80 percent of oil and gas companies’ global production, and Hamburg expects the data it gathers to drive action. Some companies, he said, will recognize that the public nature of the data makes them hard to ignore and will begin to focus on emissions. Others will need an additional nudge, whether by the public, stockholders, or regulators. Still others may need their hand forced.

Helping the cause, Hamburg said, is that momentum toward plugging methane leaks and reducing emissions has been growing. The 2021 climate summit in Glasgow saw adoption of a global pledge to reduce methane emissions 30 percent by 2030, with 150 nations signing on as of November. Last year, the U.S. approved its most sweeping climate change action to date in the Inflation Reduction Act, which includes provisions for a Methane Emissions Reduction Program.

Hamburg and Wofsy said they’re optimistic that corporations will respond relatively quickly because the fixes aren’t technically difficult, involving things such as tightening pipelines and improving wasteful processes. In addition, the methane saved can be sold as natural gas, so any remediation will at least partly pay for itself.

While oil and gas installations are MethaneSAT’s initial focus, reducing those emissions alone won’t solve the problem. They are something of a low-hanging fruit, Hamburg said. Beyond that the problem becomes more complex. That’s because methane is produced in many different ways — both natural and anthropogenic — and emissions stem not just from fossil-fuel production, but also from cities, landfills, and livestock feedlots, each of which will demand a different approach to reduction.

Back in the lab

In Wofsy’s lab and at the Center for Astrophysics, scientists, doctoral students, and postdoctoral fellows signed on due to interest in MethaneSAT’s scientific and technological challenges, but they also say they believe in the mission.

“What we’re trying to do is very attractive,” said Jonathan Franklin, a senior project scientist in Wofsy’s lab who has been with MethaneSAT since its 2015 start. “This is, obviously, the key issue of our time, and this is a way that we can make meaningful change. You need data to have success.”

MethaneSAT’s instrument works by gathering sunlight that bounces off the Earth and reflects back to the satellite’s sensors. As the light moves through the atmosphere, different molecules absorb different wavelengths. By examining the light’s spectrum, scientists can tell how much methane is present. Much of the work at Harvard and the CfA involves devising and testing an algorithm that takes that raw data, accounts for variables that might affect the readings, comes up with a value for the amount of methane present, and then uses that value to determine the methane’s source location and emission rate.

Jonas Wilzewski, a postdoctoral fellow in the Wofsy lab, said the work involves adjusting for things like different reflectivity of the ground in different places, the presence of clouds, or of aerosols in the atmosphere that might scatter the light, and dealing with local meteorological conditions.

“There are many things going on in the atmosphere, and our job is to figure out what was the actual concentration of methane in the entire column of air below the satellite,” Wilzewski said. “This algorithm starts from the signal of photons that get collected, and then goes through how much methane was in the air. Then it goes to where we see an enhancement and then calculates how much methane per time was emitted from that location, so you can say, ‘Oh, look there’s a pipeline that has a defect.’”

Wofsy said interest in MethaneSAT endures even when he tells applicants that it is not a typical scientific endeavor and likely will not result in many scientific publications. Ju Chulakadabba, a Ph.D. student, is working on methods to determine point sources of emissions from the data, and said she was drawn to it for the chance to make a difference.

Last fall, Chulakadabba flew aboard a Gulfstream V research plane from the National Science Foundation equipped with instruments similar to those that will be aboard MethaneSAT, part of a sister project called MethaneAIR. Chulakadabba and others are using MethaneAIR data to develop and test the MethaneSAT algorithm. The jet has been taking test flights out of Colorado. Soon a Lear 35A, leased and modified by EDF, will start crisscrossing the U.S. looking for methane emissions in work that will complement that of MethaneSAT.

If methane emissions fall rapidly enough to buy time for renewables to grow, it will be time that is almost certainly needed, Wofsy said. Renewables are growing faster than many projected even a few years ago, but they’re still just a fraction of global energy capacity, while signs that the globe is warming around us mount.

“We cannot electrify the entire country, transportation-wise, and go all wind and solar, in the next 10 years,” Wofsy said. “We might aspire to that, but that’s not something you can do in such a short time.”