Maintaining American Leadership through Early-Stage Research in Methane Removal
Methane is a potent gas with increasingly alarming effects on the climate, human health, agriculture, and the economy. Rapidly rising concentrations of atmospheric methane have contributed about a third of the global warming we’re experiencing today. Methane emissions also contribute to the formation of ground-level ozone, which causes an estimated 1 million premature deaths around the world annually and poses a significant threat to staple crops like wheat, soybeans, and rice. Overall, methane emissions cost the United States billions of dollars each year.
Most methane mitigation efforts to date have rightly focused on reducing methane emissions. However, the increasingly urgent impacts of methane create an increasingly urgent need to also explore options for methane removal. Methane removal is a new field exploring how methane, once in the atmosphere, could be broken down faster than with existing natural systems alone to help lower peak temperatures, and counteract some of the impact of increasing natural methane emissions. This field is currently in the “earliest stages of knowledge discovery”, meaning that there is a tremendous opportunity for the United States to establish its position as the unrivaled world leader in an emerging critical technology – a top goal of the second Trump Administration. Global interest in methane means that there is a largely untapped market for innovative methane-removal solutions. And investment in this field will also generate spillover knowledge discovery for associated fields, including atmospheric, materials, and biological sciences.
Congress and the Administration must move quickly to capitalize on this opportunity. Following the recommendations of the National Academies of Sciences, Engineering, and Medicine (NASEM)’s October 2024 report, the federal government should incorporate early-stage methane removal research into its energy and earth systems research programs. This can be achieved through a relatively small investment of $50–80 million annually, over an initial 3–5 year phase. This first phase would focus on building foundational knowledge that lays the groundwork for potential future movement into more targeted, tangible applications.
Challenge and Opportunity
Methane represents an important stability, security, and scientific frontier for the United States. We know that this gas is increasing the risk of severe weather, worsening air quality, harming American health, and reducing crop yields. Yet too much about methane remains poorly understood, including the cause(s) of its recent accelerating rise. A deeper understanding of methane could help scientists better address these impacts – including potentially through methane removal.
Methane removal is an early-stage research field primed for new American-led breakthroughs and discoveries. To date, four potential methane-removal technologies and one enabling technology have been identified. They are:
- Ecosystem uptake enhancement: Increasing microbes’ consumption of methane in soils and trees or getting plants to do so.
- Surface treatments: Applying special coatings that “eat” methane on panels, rooftops, or other surfaces.
- Atmospheric oxidation enhancement: Increasing atmospheric reactions conducive to methane breakdown.
- Methane reactors: Breaking down methane in closed reactors using catalysts, reactive gases, or microbes.
- Methane concentrators: A potentially enabling technology that would separate or enrich methane from other atmospheric components.
Figure 1. Atmospheric Methane Removal Technologies. (Source: National Academies Research Agenda)
Many of these proposed technologies have analogous traits to existing carbon dioxide removal methods and other interventions. However, much more research is needed to determine the net climate benefit, cost plausibility and social acceptability of all proposed methane removal approaches. The United States has positioned itself to lead on assessing and developing these technologies, such as through NASEM’s 2024 report and language included in the final FY24 appropriations package directing the Department of Energy to produce its own assessment of the field. The United States also has shown leadership with its civil society funding some of the earliest targeted research on methane removal.
But we risk ceding our leadership position – and a valuable opportunity to reap the benefits of being a first-mover on an emergent technology – without continued investment and momentum. Indeed, investing in methane removal research could help to improve our understanding of atmospheric chemistry and thus unlock novel discoveries in air quality improvement and new breakthrough materials for pollution management. Investing in methane removal, in short, would simultaneously improve environmental quality, unlock opportunities for entrepreneurship, and maintain America’s leadership in basic science and innovation. New research would also help the United States avoid possible technological surprises by competitors and other foreign governments, who otherwise could outpace the United States in their understanding of new systems and approaches and leave the country unprepared to assess and respond to deployment of methane removal elsewhere.
Plan of Action
The federal government should launch a five-year Methane Removal Initiative pursuant to the recommendations of the National Academies. A new five-year research initiative will allow the United States to evaluate and potentially develop important new tools and technologies to mitigate security risks arising from the dangerous accumulation of methane in the atmosphere while also helping to maintain U.S. global leadership in innovation. A well-coordinated, broad, cross-cutting federal government effort that fosters collaborations among agencies, research universities, national laboratories, industry, and philanthropy will enable the United States to lead science and technology improvements to meet these goals. To develop any new technologies on timescales most relevant for managing earth system risk, this foundational research should begin this year at an annual level of $50–$80 million per year. Research should last ideally five years and inform a more applied second-phase assessment recommended by the National Academies.
Consistent with the recommendations from the National Academies’ Atmospheric Methane Removal Research Agenda and early philanthropic seed funding for methane removal research, the Methane Removal Initiative would:
- Establish a national methane removal research and development program involving key science agencies, primarily the National Science Foundation, Department of Energy, and National Oceanic and Atmospheric Administration, with contributions from other agencies including the US Department of Agriculture, National Institute of Standards and Technology, National Aeronautics and Space Administration, Department of Interior, and Environmental Protection Agency.
- Focus early investments in foundational research to advance U.S. interests and close knowledge gaps, specifically in the following areas:
- The “sinks” and sources of methane, including both ground-level and atmospheric sinks as well as human-driven and natural sources (40% of research budget),
- Methane removal technologies, as described below (30% of research budget); and
- Potential applications of methane removal, such as demonstration and deployment systems and their interaction with other climate response strategies (30% of research budget).
The goal of this research program is ultimately to assess the need for and viability of new methods that could break down methane already in the atmosphere faster than natural processes already do alone. This program would be funded through several appropriations subcommittees in Congress, most notably Energy & Water Development and Commerce, Justice, Science and Related Agencies. Agriculture, Rural Development, Food and Drug Administration, and Interior and Environment also have funding recommendations relevant to their subcommittees. As scrutiny grows on the federal government’s fiscal balance, it should be noted that the scale of proposed research funding for methane removal is relatively modest and that no funding has been allocated to this potentially critical area of research to date. Forgoing these investments could result in neglecting this area of innovation at a critical time where there is an opportunity for the United States to demonstrate leadership.
Conclusion
Emissions reductions remain the most cost-effective means of arresting the rise in atmospheric methane, and improvements in methane detection and leak mitigation will also help America increase its production efficiency by reducing losses, lowering costs, and improving global competitiveness. The National Academies confirms that methane removal will not replace mitigation on timescales relevant to limiting peak warming this century, but the world will still likely face “a substantial methane emissions gap between the trajectory of increasing methane emissions (including from anthropogenically amplified natural emissions) and technically available mitigation measures.” This creates a substantial security risk for the United States in the coming decades, especially given large uncertainties around the exact magnitude of heat-trapping emissions from natural systems. A modest annual investment of $50–80 million can pay much larger dividends in future years through new innovative advanced materials, improved atmospheric models, new pollution control methods, and by potentially enhancing security against these natural systems risks. The methane removal field is currently at a bottleneck: ideas for innovative research abound, but they remain resource-limited. The government has the opportunity to eliminate these bottlenecks to unleash prosperity and innovation as it has done for many other fields in the past. The intensifying rise of atmospheric methane presents the United States with a new grand challenge that has a clear path for action.
Methane is a powerful greenhouse gas that plays an outsized role in near-term warming. Natural systems are an important source of this gas, and evidence indicates that these sources may be amplified in a warming world and emit even more. Even if we succeed in reducing anthropogenic emissions of methane, we “cannot ignore the possibility of accelerated methane release from natural systems, such as widespread permafrost thaw or release of methane hydrates from coastal systems in the Arctic.” Methane removal could potentially serve as a partial response to such methane-emitting natural feedback loops and tipping elements to reduce how much these systems further accelerate warming.
No. Aggressive emissions reductions—for all greenhouse gases, including methane—are the highest priority. Methane removal cannot be used in place of methane emissions reduction. It’s incredibly urgent and important that methane emissions be reduced to the greatest extent possible, and that further innovation to develop additional methane abatement approaches is accelerated. These have the important added benefit of improving American energy security and preventing waste.
More research is needed to determine the viability and safety of large-scale methane removal. The current state of knowledge indicates several approaches may have the potential to remove >10 Mt of methane per year (~0.8 Gt CO₂ equivalent over a 20 year period), but the research is too early to verify feasibility, safety, and effectiveness. Methane has certain characteristics that suggest that large-scale and cost-effective removal could be possible, including favorable energy dynamics in turning it into CO2 and the lack of a need for storage.
The volume of methane removal “needed” will depend on our overall emissions trajectory, atmospheric methane levels as influenced by anthropogenic emissions and anthropogenically amplified natural systems feedbacks, and target global temperatures. Some evidence indicates we may have already passed warming thresholds that trigger natural system feedbacks with increasing methane emissions. Depending on the ultimate extent of warming, permafrost methane release and enhanced methane emissions from wetland systems are estimated to potentially lead to ~40-200 Mt/yr of additional methane emissions and a further rise in global average temperatures (Zhang 2023, Kleinen 2021, Walter 2018, Turetsky 2020). Methane removal may prove to be the primary strategy to address these emissions.
Methane is a potent greenhouse gas, 43 times stronger than carbon dioxide molecule for molecule, with an atmospheric lifetime of roughly a decade (IPCC, calculation from Table 7.15). Methane removal permanently removes methane from the atmosphere by oxidizing or breaking down methane into carbon dioxide, water, and other byproducts, or if biological processes are used, into new biomass. These products and byproducts will remain cycling through their respective systems, but without the more potent warming impact of methane. The carbon dioxide that remains following oxidation will still cause warming, but this is no different than what happens to the carbon in methane through natural removal processes. Methane removal approaches accelerate this process of turning the more potent greenhouse gas methane into the less potent greenhouse gas carbon dioxide, permanently removing the methane to reduce warming.
The cost of methane removal will depend on the specific potential approach and further innovation, specific costs are not yet known at this stage. Some approaches have easier paths to cost plausibility, while others will require significant increases in catalytic, thermal or air processing efficiency to achieve cost plausibility. More research is needed to determine credible estimates, and innovation has the potential to significantly lower costs.
Greenhouse gases are not interchangeable. Methane removal cannot be used in place of carbon dioxide removal because it cannot address historical carbon dioxide emissions, manage long-term warming or counteract other effects (e.g., ocean acidification) that are results of humanity’s carbon dioxide emissions. Some methane removal approaches have characteristics that suggest that they may be able to get to scale quickly once developed and validated, should deployment be deemed appropriate, which could augment our near-term warming mitigation capacity on top of what carbon dioxide removal and emissions reductions offer.
Methane has a short atmospheric lifetime due to substantial methane sinks. The primary methane sink is atmospheric oxidation, from hydroxyl radicals (~90% of the total sink) and chlorine radicals (0-5% of the total sink). The rest is consumed by methane-oxidizing bacteria and archaea in soils (~5%). While understood at a high level, there is substantial uncertainty in the strength of the sinks and their dynamics.
Up until about 2000, the growth of methane was clearly driven by growing human-caused emissions from fossil fuels, agriculture, and waste. But starting in the mid-2000s, after a brief pause where global emissions were balanced by sinks, the level of methane in the atmosphere started growing again. At the same time, atmospheric measurements detected an isotopic signal that the new growth in methane may be from recent biological—as opposed to older fossil—origin. Multiple hypotheses exist for what the drivers might be, though the answer is almost certainly some combination of these. Hypotheses include changes in global food systems, growth of wetlands emissions as a result of the changing climate, a reduction in the rate of methane breakdown and/or the growth of fracking. Learn more in Spark’s blog post.
Methane has a significant warming effect for the 9-12 years that it remains in the atmosphere. Given how potent methane is, and how much is currently being emitted, even with a short atmospheric lifetime, methane is accumulating in the atmosphere and the overall warming impact of current and recent methane emissions is 0.5°C. Methane removal approaches may someday be able to bring methane-driven warming down faster than with natural sinks alone. The significant risk of ongoing substantial methane sources, such as natural methane emissions from permafrost and wetlands, would lead to further accumulation. Exploring options to remove atmospheric methane is one strategy to better manage this risk.
Research into all methane removal approaches is just beginning, and there is no known timeline for their development or guarantee that they will prove to be viable and safe.
Some methane removal and carbon dioxide removal approaches overlap. Some soil amendments may have an impact on both methane and carbon dioxide removal, and are currently being researched. Catalytic methane-oxidizing processes could be added to direct air capture (DAC) systems for carbon dioxide, but more innovation will be needed to make these systems sufficiently efficient to be feasible. If all planned DAC capacity also removed methane, it would make a meaningful difference, but still fall very short of the scale of methane removal that could be needed to address rising natural methane emissions, and additional approaches should be researched in parallel.
Methane emissions destruction refers to the oxidation of methane from higher-methane-concentration air streams from sources, for example air in dairy barns. There is technical overlap between some methane emissions destruction and methane removal approaches, but each area has its own set of constraints that will also lead to non-overlapping approaches, given different methane concentrations to treat, and different form-factor constraints.
A deeper understanding of methane could help scientists better address these impacts – including potentially through methane removal.
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