The nascent U.S. campaign to monitor emissions of carbon dioxide, methane and other potent greenhouse gases will require important contributions from NASA, the National Oceanic and Atmospheric Administration and dozens of other public and private organizations.
In recent years, the United States has lagged behind Europe, Japan and China in developing space-based infrastructure for measuring and monitoring greenhouse gas emissions. The Biden administration, which set a goal of slashing emissions by 50 percent by 2030, based on 2005 levels, is taking steps to remedy that.
In January 2022, the Biden administration established the Greenhouse Gas Monitoring and Measurement Interagency Working Group, led by the White House Office of Science and Technology Policy, Office of Management and Budget and the White House Climate Policy Office. The working group coordinates efforts by federal agencies to identify and employ tools and data systems to measure and monitor atmospheric greenhouse gas emissions and the removal of atmospheric greenhouse gases.
Forging common understanding
Establishing a robust measuring system won’t be easy. Current estimates of greenhouse gas levels rely heavily on observations made by ground-based and airborne sensors coupled with industry estimates. How many tons of coal and barrels of oil, for example, were consumed in a month?
In recent years, satellite sensors have proven their ability to contribute global observations of greenhouse gas emissions and reveal fluctuations in greenhouse gases stemming from human and natural sources. For instance, satellites showed striking changes in atmospheric pollutants prompted by COVID-19 lockdowns.
Combining the ground, air and space measurements is “important to seeing the holistic picture,” said Karen St. Germain, NASA Earth Science Division director.
In addition, a comprehensive tally of greenhouse gases emissions requires “a coordinated mechanism to bring together federal, state, local, philanthropic, commercial and academic capabilities to provide high-quality transparent data and information at spatial and temporal scales that meet user and decision-maker needs,” St. Germain said.
Still, figuring out how agencies can work together to forge a common understanding of greenhouse gas levels based on these varied datasets is “an area of scientific and technical inquiry and work right now,” St. Germain said.
The working group has drafted a strategy for creating an integrated U.S. greenhouse gas monitoring and information system. The strategy includes near-term steps and demonstration projects by federal agencies.
Now, the working group is preparing to seek public comment on its draft strategy and public help in identifying “significant gaps or omissions as well as opportunities for federal agencies to partner with external entities on the framework,” St. Germain said.
NASA has a long history of publicly sharing observations of atmospheric concentrations of greenhouse gases obtained with airborne instruments and field campaigns. Space agency researchers also have developed innovative instruments and techniques to measure carbon dioxide in Earth’s atmosphere.
With the second Orbiting Carbon Observatory launched in 2014, NASA observes the geographical distribution of carbon dioxide sources and the sinks, like oceans and forests, that absorb and store the chemical compound.
A third Orbiting Carbon Observatory remains mounted to the exterior of the International Space Station. Later this year, instead of being released to burn up in Earth’s atmosphere as expected when OCO-3 launched in 2019, the 500-kilogram instrument will be moved to an ISS storage module while a technology demonstration takes its place on the space station platform. When that six-month technology demonstration is completed, NASA will move OCO-3 outside to continue gathering data.
“We’re working with the team right now to make sure that we can bring OCO-3 back and keep it operating,” said David Crisp, principal investigator for the NASA Orbiting Carbon Observatory missions.
NASA’s decision to extend the OCO-3 mission was due, in part, to the cancellation last year of the Geostationary Carbon Cycle Observatory. When that decision was announced in November, NASA officials also pledged to prioritize a greenhouse gas mission for the Earth System Explorers line of competed Earth science missions.
With GeoCarb, NASA planned to observe atmospheric carbon dioxide, carbon monoxide and methane concentrations over most of North and South America. The GeoCarb mission ran into a series of cost and technical obstacles after NASA could not find a commercial communications satellite to accommodate the hosted payload.
As part of its work to monitor greenhouse gases, NASA also is evaluating data provided by GHGSat, a Canadian company that tracks methane emissions with six satellites, as part of the agency’s Commercial Smallsat Data Acquisition program. And another NASA instrument, the Earth Surface Mineral Dust Source Investigation on the space station, an instrument designed to identify minerals in desert dust, has shown it can also detect significant methane plumes.
NASA is focused on making its own observations “more accessible and just as importantly combining the observations with other sources of data to make the user experience easier and more efficient,” St. Germain said. “We are enhancing existing greenhouse gas data products and working in the interagency, intergovernmental and also with private sector partners to co-develop and increase the adoption of these kinds of applications.”
Trusted Data Source
Similarly, multiple NOAA programs contribute to global understanding of greenhouse gas concentrations.
NOAA instruments, like the Crosstrack Infrared Sounder on the Joint Polar Satellite System, reveal greenhouse gas concentrations in the troposphere. NOAA’s Office of Oceanic and Atmospheric Research shares information on carbon dioxide, methane, nitrous oxide and dozens of trace gases detected in air samples collected by NOAA’s global greenhouse gas network. And NOAA sensors track ocean acidification caused by absorbed carbon dioxide.
In addition, NOAA’s Center for Satellite Applications and Research is developing a system to validate greenhouse gas observations made by NOAA partners.
“Our role is to provide that data source and make sure that regardless of where it comes from, it’s actually a trusted source of data,” Mitch Goldberg, chief scientist for NOAA’s National Environmental Satellite Data and Information Service, said at the American Meteorological Society meeting in January. “A trusted source of data means that you understand the underpinning science and also provide the stewardship and the validation of those products.”
For example, NOAA is offering to help validate and characterize greenhouse gas measurements obtained by GHGSat and similar ventures, “so we have a common understanding of the database for greenhouse gas observations,” Stephen Volz, NOAA Satellite and Information Service assistant administrator, said at the AMS meeting. “We do not yet have in our portfolio a NOAA greenhouse gas monitoring mission for atmospheric composition.”
It’s too soon to say whether a federal agency will eventually be tasked with overseeing atmospheric greenhouse gas monitoring.
Crisp, who retired from NASA in 2022 and works with international agencies coordinating global campaigns to track greenhouse gas, thinks NOAA is the most likely candidate.
“NOAA is an operational agency set up to deliver operational products to support U.S. policy,” Crisp said. “NOAA would need the resources to put together the operational systems to carry on the operation of the satellites and deliver their [data] products to users.”
The European Commission is spending approximately 2 billion euros on the three-satellite Copernicus Carbon Dioxide Monitoring mission, known as CO2M.
Likewise, NOAA or another U.S. government agency would need a budget of about $2 billion over 10 years to establish an operational greenhouse gas monitoring system, Crisp said.
While that cost is high, “wouldn’t it be nice to have a measurement system as we get deeper and deeper into climate change,” Crisp asked.
Even if the money were promised today, it would take the United States approximately five years to develop and deploy a constellation to monitor atmospheric carbon dioxide and methane, Crisp said.
This article originally appeared in the February 2023 issue of SpaceNews magazine.