Methane is a powerful greenhouse gas — 84 times stronger than carbon dioxide over 20 years. Because it traps heat more intensely in the short-term than other GHGs, cutting methane emissions now can have a fast and significant impact on slowing climate change.
A good place to start is farms. Nearly half of global methane emissions come from agricultural activities such as livestock production, rice cultivation and burning crop waste. And with global food demand rising, these emissions are projected to grow.
The good news is that promising approaches are emerging to rein in agriculture’s climate impact. A new WRI report provides the latest scientific updates, as well as economic considerations for over 25 methane mitigation solutions.
But First, Where Do Agricultural Methane Emissions Come From?
Livestock are far and away the biggest source of agricultural methane, producing about two-thirds of the total. Most of it comes from “ruminant” animals’ digestion and manure.
Ruminants like cattle, sheep and goats naturally produce methane as a byproduct of digestion, known as “enteric fermentation.” Microorganisms in their stomachs break down food, generating methane that is mainly released through burping. Ruminant livestock account for over 55-60% of agriculture’s methane emissions — non-ruminants like pigs and horses contribute far less.
Manure produces 6-8% of agricultural methane emissions (though some research suggests these emissions could be significantly higher). In large dairy and pork production facilities, or “factory farms,” manure is often flushed outside using a water jet and put into tanks or lagoons, where it is stored as liquid or slurry. These wet systems create ideal conditions for methane-producing microorganisms. In contrast, small- to medium-sized farms — where manure is typically stored in its solid form or dried in the sun — emit less methane.
Rice farming is another major methane source, producing 18-20% of agricultural methane emissions. Flooded rice fields deplete oxygen and fuel methane production. The gas then escapes mainly through rice plants or as bubbles that rise from the soil — though emissions vary depending on irrigation methods, soil types and fertilizer use.
Burning crop “residues”— waste leftover once crops are harvested, such as rice and wheat stalks and other biomass — is a common practice in some countries, contributing 3-4% of agricultural methane emissions while also spewing air pollution and endangering human health.
Dozens of strategies have emerged in recent years to reduce these emissions, ranging from low-tech to high-tech. But costs, feasibility and stage of development vary considerably. Here are a handful of solutions that, with refinement and supportive R&D, could be promising:
1) Making Livestock More Efficient
In many developing countries, livestock produce far less milk and meat per animal than farms in places like the U.S. There’s a big opportunity to make animal production more efficient by improving the quality of animal diets, breeding higher-quality livestock, and ensuring better animal health. These improvements can help farmers increase productivity without increasing total methane emissions — as long as the methane produced per unit of milk or meat decreases enough to offset the increase in production.
One proven way to do this is by feeding animals more digestible feed, which helps them both burp less and absorb more nutrients for growth and milk production. In the U.S., for example, milk production grew by 53% between 1990 and 2021, while enteric methane emissions per unit of milk decreased by about 25% (though there were also significant increases in manure management emissions during this period). While many farms in developed countries already use highly digestible feeds, farmers in Africa and South Asia often feed their animals low-quality crop residues such as rice straw and wheat straw, which can make up to 70% of a cow’s diet. While feeding animals crop residues prevents emissions that would otherwise result from burning them, farmers could also enrich crop residues with nutrients and biochemical methods to boost animal productivity. These benefits are especially significant for low-producing cows, helping them grow bigger and produce more milk while reducing methane emissions.
In an upcoming project, WRI will work with the International Livestock Research Institute (ILRI) in Ethiopia and Nepal to develop sustainable ways of turning crop residues into high-quality animal feed, which can in turn reduce methane emissions, boost production and create local jobs.
2) Stopping Methane Before it Escapes: Methane Inhibitors
One way farms can further cut emissions is by using methane-inhibiting feed additives, which can help reduce the amount of methane cows produce during digestion. These inhibitors are particularly suitable for commercial and large-scale farms, as cost can be a barrier for small-scale farms and methane inhibitors do not always result in productivity gains.
For example, a synthetic molecule called 3-nitroxypropanol (3-NOP) has gathered interest in the last few years, undergoing extensive R&D trials and securing regulatory approval for use in beef or dairy cows in over 60 countries. Given in small doses through cow feed, it can reduce methane production by around 30%. Currently it is applicable for cows in feedlots, and systems that can deliver 3-NOP to grazing cows are under development. However, it doesn’t boost productivity, so acceptance will depend on costs. Some food and supply chain companies, like Arla Foods UK, are trialing the commercially approved 3-NOP (Bovaer™) on dairy farms with major retailers. Despite extensive safety studies, consumer misinformation has caused some backlash. Further, one recent long-term study indicated that the effects of 3-NOP could largely depend on diet type and may decrease as the cow progresses in her lactation cycle. This suggests that having a second, complementary inhibitor that can be alternated with 3-NOP would be very valuable.
Another methane-inhibiting feed additive that has secured considerable market interest in recent years is red seaweed, or Asparagopsis. Red seaweed is native to Australia and approved for use in beef feedlots in the country. While research shows that its methane mitigation potential can reach up to 90%, long-term trials have shown about 30% effectiveness in reducing methane.
One option that could reduce costs is to use only its active ingredient, bromoform, in some form. A challenge is that bromoform has been identified as a “probable human carcinogen” although there is a good chance that when small quantities are added to feed, they are broken down in the cow’s digestive system. While some large-scale production has begun, more R&D is needed to address the potentially high production costs and human health impacts.
3) Breeding Low-Methane Cows
Methane production from cows is linked to their genetics, with some cows inherently producing more methane than others. Selecting superior-quality breeds that are healthier and feed-efficient is a long-standing farm practice. Similarly, breeding and selecting low-methane cows that naturally emit less methane is possible. On average, low-methane cows can produce 22% less methane emissions than high-emitting ones. As opposed to methane inhibitors, methane mitigation lasts the entire lifespan of a cow and may even be passed down to offspring.
While there have been some pilots around the world, such as in Canada and New Zealand, this approach still needs significant R&D and farmer education for widescale impact. However, if adopted widely, the benefits of methane reduction could be profound, as this solution can be applied across all production systems and geographies.
4) Anti-Methane Vaccines
Another emerging solution in its early research phase focuses on vaccines that prevent methane formation in cows’ stomachs. These methane vaccines can be administered just like any other vaccine to calves, and the effect lasts through a cow’s life. Some promising R&D efforts on vaccines are currently targeting a 30% methane reduction. If successful, methane vaccines hold great potential for broader adoption, as vaccination infrastructure is well-developed in most parts of the world.
5) Alternatives to Manure Digesters
When it comes to reducing methane from manure management, digesters receive the most attention.
Biogas digesters use manure to produce biogas, which is a mixture of methane and carbon dioxide. Digester projects capture this methane to produce electricity or compress it to make “renewable natural gas.” While digesters are capable of reducing methane emissions, our report notes that reductions have often been overestimated by failure to account for methane leaks from the digester and emissions from the “digestate,” the wet material that emerges from the digester at the end and produces methane.
One big problem with digesters is their cost. In the U.S., a farm usually needs at least 500 cows for a digester to make financial sense. That leaves small- and medium-sized farms out of the picture. At the same time, digesters get heavy subsidies and policy support as renewable energy solutions. They also produce wastewater that emits more ammonia than raw manure and negatively affects water quality. Another potential problem is that in many countries, crops are added to digesters. The land use requirements and associated emissions from growing crops, along with methane leaks, tend to undermine any methane-reduction benefits from the digester.
Meanwhile, in countries like India and China, millions of small-scale, household-level digesters have been in use for decades. While they provide cooking fuel and enhance energy security, poor monitoring and methane leakage may have led to higher overall emissions.
For these reasons, alternatives to digesters are needed. One promising alternative involves various forms of solid-liquid separation. In this approach, farmers use mechanical equipment to separate the solid part of manure from the liquid. The solid part is then typically composted, dried or used as bedding for cows, and the liquid portion is stored in tanks or lagoons. This method can reduce methane by up to 60%, depending on the type of technology used, and we estimate the costs to be much less than digesters. California’s Alternative Manure Management Program has supported installing several solid separators in the state, but their global adoption overall is still limited mostly due to a lack of grants, subsidies or other financial instruments for farmers.
Another promising technology is acidification, or mixing manure with acid. Acidic manure creates unfavorable conditions for methane-forming microorganisms and hence reduces methane emissions. This approach is most commonly used in Denmark as part of the country’s ammonia control regulation. Literature highly supports acidification to achieve reductions in methane, nitrous oxide and ammonia emissions, though the extent of these benefits depend on the frequency, type and dosage of acid used. Researchers report up to a 89% reduction in methane using higher acid doses and a 46% reduction with lower doses.
These alternative technologies are in their early stages of adoption and deserve more on-farm trials to test their efficacy, trade-offs and potential co-benefits.
6) Curbing Methane from Rice
Many approaches can help reduce methane emissions from rice farming, beginning with adopting high-yielding rice varieties that can significantly lower methane emissions per kilogram of rice produced. Also, among thousands of rice breeds worldwide, some naturally emit less methane than others. Identifying and cultivating these low-methane varieties could reduce emissions by 22-51%.
One such promising variety is SUSIBA 2, which has been adopted in some parts of the world. A 2025 study appears to have uncovered the biochemical mechanisms behind SUSIBA 2’s ability to release less methane: methane-suppressing chemicals in their root systems. Such innovation could pave the way for breeding superior rice varieties that emit up to 70% less methane.
A simple and inexpensive way to reduce methane from rice production is Alternative Wetting and Drying (AWD). Rice grows in “flooded” fields; AWD involves letting the water completely dry before flooding again. Several variations of this practice exist and can reduce methane emissions by 40-45%. This approach also saves water, benefitting water-scarce regions. However, the ability to use AWD depends on the reliability of drainage and water supplies. Since most rice farmers have small plots of land, adopting AWD works best when multiple farms coordinate their water management. This requires community-level projects to manage water levels effectively and provide farmers with the right support and incentives.
Moving from Research to Action
In reality, governments have devoted extremely limited resources toward addressing methane mitigation on farms, but the exciting news is the emergence of promising solutions even with limited funds. Even modest increases in finance would likely fuel greater progress. Governments need to approach these solutions the way they have approached solutions in the energy sector, with support and investment directed at innovation. While some strategies seem ready to expand rapidly, others require reasonable funding for R&D and support for large-scale pilot projects.
Governments could accelerate the adoption of methane mitigation technologies by providing targeted subsidies for farmers and integrating methane reduction into broader agricultural policies. To reduce emissions from livestock and rice production, countries should lay out strategies that capture their unique production systems and focus on capacity-building to adopt long-term sustainable solutions that could also improve food security.
Meanwhile, the private sector must invest in trials and R&D to continuously improve emerging mitigation technologies and make their learnings available to the public. More pilot projects can help secure consumer acceptance before large-scale trials are rolled out. Multi-million dollar R&D Initiatives can have a profound impact on advancing science and making research accessible to everyone. One example is the Enteric Fermentation R&D Accelerator, which funds breakthrough research in technologies that reduce livestock methane emissions, making them attractive for farmers and adaptable to diverse production systems globally. More open data-sharing can also accelerate field trials.
Ultimately, governments and the private sector must work together to support livestock and rice farmers. With the right practices and technologies, farms around the world can both enhance food security while slowing climate change.