Human-induced methane emissions are one of the most significant drivers of climate change. Human activity has caused 2/3 of methane currently present in the atmosphere. Humans have been spewing methane into the atmosphere at a rate not seen in 800,000 years. People have largely been focused on carbon dioxide as the main culprit for global warming. Methane received hardly, if any, attention. But that is changing thanks to science. We no longer have the luxury of overlooking methane.
Glasgow’s 26th international climate conference launched a new initiative to tackle methane emissions. At the meeting, more than a hundred countries responsible for more than half of global methane emissions committed to reducing levels by 30% by 2100.
Methane forms ground-level ozone. Ground-level ozone is a hazardous air pollutant and greenhouse gas. Exposure to it causes 1 million premature deaths every year.
Although it is a short-lived pollutant (12 years), methane is a much more powerful greenhouse gas than carbon dioxide. Methane is 80 times more potent at warming than carbon dioxide over a 20-year period. Over a 100-year period, methane traps 28 times more heat than carbon dioxide. Methane has been responsible for 40% of global warming since the pre-industrial period. Methane emissions in the 21st century have risen faster than at any other time since the world began keeping records in the 1980s. According to the National Oceanic and Atmospheric Administration of the United States, even while carbon emissions decreased during the lockdown due to the 2020 pandemic, methane emissions rose.
Sources of Methane Emissions
Methane emissions from livestock production went up by 17.5% between 1990 and 2019. Enteric fermentation in animals is the primary source of methane emissions. Burps from ruminant animals, especially dairy and beef cattle, release methane.
The other primary source of methane emissions from livestock production comes from concentrated animal feeding operations (CAFOs). Over the past few decades, the dairy and pork industries have grown immensely. With them, concentrated production systems containing liquid waste lagoons have also expanded, driving up methane emissions.
Even crop agriculture emits methane, especially rice cultivation. Farmers around the world mainly grow rice in fields flooded with water. The water does not allow oxygen to penetrate the soil. This creates ideal living conditions for methane-emitting bacteria. Rice is responsible for 11% of all human-made methane emissions.
3. Oil and Gas Operations
Fossil fuel operations are responsible for one-third of all methane emissions.
We usually encounter natural gas while exploring for oil. Oil and natural gas occur together and under the same conditions. While drilling for oil, when producers find an amount of natural gas that is too small to sell economically, they burn (or flare) it. Methane is even released intentionally while cleaning oil wells. Sometimes, producers intentionally release natural gas to reduce pressure in the well. This is called venting. Both the processes of venting and flaring lead to releases of methane. Methane can also escape in small leaks from valves and other equipment used when drilling for and producing oil.
Landfills release methane due to the decomposition of organic matter like food, wood, and paper. It provides methane-emitting bacteria with plenty of organic waste and anaerobic conditions to thrive.
5. Coal Mining
Coal mining is responsible for 10-15% of anthropogenic methane emissions. Coal-mine-methane (CMM) emissions can escape from either working or abandoned deep mines. When coal forms, methane forms, too, as a byproduct. Therefore, when we explore coal, we intentionally or unintentionally release methane into the atmosphere.
Five industries are responsible for 98% of the world’s methane emissions. We’ll take a look at each of them and explore ways they can reduce Methane emissions.
Several companies have started commercializing feed additives for cattle. These feed additives help cattle better digest their food, leading to fewer methane emissions when they belch.
Governments need to educate and incentivize farmers to adopt sustainable practices for cultivating rice. We need more research and alternative approaches to water, soil, and land management in farming.
3. Oil and Gas Operations
We can avoid almost 45% of methane emissions from oil and gas operations with measures that have no net cost. Policymakers can introduce a ban on non-emergency venting and flaring. They can even make it mandatory for oil wells to reduce emissions using tools like Leak Detection and Repair requirements (LDAR).
When a landfill reaches its full capacity and cannot be used any longer, landfill operators can cover it with biosolids instead of just leaving it open. Biosolids create unique topsoil. This topsoil contains microorganisms that convert methane into carbon dioxide. Carbon dioxide is less potent than methane at trapping heat. Biosolids can reduce methane emissions from landfills by as much as 95%. Alternatively, landfill managers can even deploy available technology that captures the methane emissions and turns them into electricity.
Another important method of reducing methane emissions from landfills is composting. Local bodies should make it mandatory for people to segregate their waste. They can use the wet waste to make compost and sell it to farmers, while the dry waste can be sent to recycling facilities. This eliminates waste altogether and creates a circular, sustainable economy.
5. Coal Mining
We can develop ventilation and drainage systems that capture CMM before it escapes into the atmosphere. We can use the captured methane to generate heat, electricity, and fuel as compressed or liquefied natural gas.
Three No-Regret Actions for Methane Reductions
To begin reducing methane emissions, we need sound groundwork. The three no-regret actions ensure we are within reach of meeting the goals of the Paris Agreement, which include limiting warming to 1.5oC.
We must develop a collective and concerted effort to expand monitoring, reporting, and verification. Industries and governments need to improve on data collection and measuring methane emissions. With better measurements, we can create better incentives for rapid reduction in methane emissions across industries.
2. Support Sustainable Consumption
Producers must work on selling their products with a methane footprint so that consumers can make informed, responsible decisions. If every kilogram of rice, a ton of coal, a barrel of oil, and a pound of meat came with a methane footprint label, we’d already have fewer methane emissions.
3. Increase Innovation
We can develop all the practical solutions we want. But high costs and lack of awareness of available technology will allow those solutions to be adopted on a large scale. For example, methane monitoring innovations in the oil and gas industry can help businesses pinpoint leaks. The livestock industry is in the early stages of feed additives and methane capture. Support could help these technologies move speedily from lab to field.
Dr. Emily Greenfield is a highly accomplished environmentalist with over 30 years of experience in writing, reviewing, and publishing content on various environmental topics. Hailing from the United States, she has dedicated her career to raising awareness about environmental issues and promoting sustainable practices.