Methane Madness
Reducing methane emissions from natural gas, cow gas, and landfill gas offers the best chance of slowing the warming of the planet
For the next two decades, what the world does about methane emissions will have the greatest impact on climate change. Methane, the primary component of natural gas, is a potent greenhouse gas with an impact 84 times that of CO2 over a 20-year timescale. Unlike CO2, which remains in the atmosphere for centuries, methane largely dissipates after 10–12 years. Consequently, a substantial reduction in methane emissions could reduce warming by over 0.2C by 2040, a substantial contribution to meeting the Paris goals. In contrast, reducing burning of coal does not reduce warming for at least a decade due to the associated reduction of co-emitted sulfates, particles which reflect sunlight and cool the atmosphere. However, despite recent efforts to detect and capture methane leaks from pipelines and coal mines, emissions continue to increase and in the U.S. reached record levels.
A Global Methane Pledge initiated at COP26 in 2021 has been signed by 155 nations including the U.S. representing over 50% of global anthropogenic emissions. Signatories promise to reduce total methane emissions from all sources by 30 percent by 2030. Notably, the agreement is voluntary and not supported by Russia; China and India are not signatories but have made some commitments to action. At COP28, 50 of the world’s largest oil and gas companies agreed to voluntarily limit their methane emissions to near-zero by 2030 and to allow monitoring of their emissions by several independent organizations.
The Many Sources of Methane
Most discussion of methane emissions has focused on leakage from production and distribution of oil and gas, and secondarily on emissions from coal mines. However, agriculture, particularly enteric fermentation ( gases emitted from cows and other ruminants), and landfills are larger sources of methane worldwide and in the U.S than fossil fuel sources. Manure lagoons, too, are a surprisingly large source of emissions. Some landfills now capture and burn methane for power, but finding practical and economic solutions to emissions from cows and other ruminants has so far proven challenging. Among the barriers to addressing these emissions is the agriculture lobby, which has so far insulated farms from even reporting emissions.
Sources of U.S. Methane Emissions (1990–2021): U.S. EPA (2023)
In addition to the many human sources of methane, natural sources include the melting of permafrost due to global warming. A huge amount of carbon is stored in permafrost, twice as much as in the atmosphere, and with thawing organic material will break down releasing some combination of CO2 and methane. This could happen rapidly, in months or a few years, in a feedback loop that accelerates warming. How soon and how fast this occurs is the subject of increasing scientific investigation — and great concern.
Production of “Transition Fuels” (a/k/a Natural Gas) also Releases Methane.
A major challenge to efforts to reduce methane emissions has emerged in support for continued use of natural gas as a “transition fuel,” a designation included in the text agreed at COP28. Paragraph 28(g) “Recognizes that transitional fuels can play a role in facilitating the energy transition while ensuring energy security.” The language of “transitional fuels” is widely understood to allow for continued and even greater use natural gas. Immediately upon the COP conclusion, several announcements were made of large investments in gas production, pipelines, and power plants. This is evidence that the markets found that the text did not threaten such investments. Some African countries were particularly disappointed by the prospect of gas investments lasting decades; while renewables cost less than gas long term, the upfront cost with renewables is much greater, while gas is purchased over time.
The case for thinking of natural gas as a “transition” fuel rests on the fact that under certain circumstances it emits less pollution and can be burned to generate power much more efficiently than coal or oil, thus emitting less CO2. However, the production and distribution of natural gas has been, and continues to be, the source of enormous methane leakage. The technology to identify and capture leaking gas has improved with the economic benefits going to producers and distributors. (You may have seen the oil company advertisement featuring young boys gleefully following drones flying over a pipeline.) A recent assessment by the International Energy Agency concludes that, based on recent gas prices, about 80% of the measures needed to reduce methane emissions from oil and gas operations worldwide could be implemented at no net cost with an upfront investment of about $100 billion — less than 3% of the industry’s net income in 2022.
Several cities including New York, Seattle, and Washington, D.C have adopted restrictions on use of natural gas in new buildings in support of health and climate goals. In response, twenty states controlled by Republican legislatures have passed laws overriding and banning such restrictions and a court found the regulation preempted by federal appliance standards. In an attempt to circumvent the state and court prohibitions, cities are now promoting zero emission requirements.
So what to do?
Given the potential benefits of accelerating and expanding measures to reduce methane emissions, more ambitious international efforts are urgently needed. One immediate and modest step would be to increase public funding for reducing non-energy related emissions. While many long-term unproven climate mitigation technologies like direct air capture and green hydrogen are receiving tens of billions of dollars, this potentially high payoff solution only recently became the focus of a $200 million program, much of it from philanthropies. Several promising new initiatives focused on agriculture emissions were announced at COP28. Another significant new area of research is a focus on methane removal and destruction, also worthy of greater support.
While more challenging to accomplish, the most effective response would be an international agreement mandating methane emission reductions. In the book Cut Super Climate Pollutants Now!, Durwood Zaelke, Stephen O. Andersen and I make the case for such an agreement modeled after the successful Montreal Protocol, the treaty that protects the ozone layer — notably negotiated in only two years. The goal of the recently initiated negotiation on a treaty to reduce plastic pollution is also to conclude in two years. And as Zaelke and Paul Bledsoe argue in a recent Boston Globe op-ed, “The United States and the European Union have just announced tough new rules to reduce methane, giving them and their industries the incentive to support a global agreement that ensures the rest of the world follows the same rules.”
A focus on short-term reductions in methane emissions is not in conflict with the fundamental need for dramatic reduction in use of fossil fuels and CO2 emissions. Both are urgently needed, what we characterize as the climate “sprint and marathon” in Cut Super Climate Pollutants Now!
Negotiating international agreements usually requires years. The planet no longer has time to wait. Aggressive global efforts to reduce methane emissions should be an urgent priority for climate action at local, national, and international levels.
