How Methane Emissions Contribute to Climate Change
The United States and the European Union announced a new pledge to reduce global methane emissions by at least 30% by 2030 relative to 2020 levels, with the intention that many more major emitters will join on in the lead up to the annual climate conference in Glasgow later this year. For the first time, the pledge sets the floor for what’s necessary to curb this dangerous climate pollutant over the next decade.
This announcement couldn’t come soon enough, because cutting methane emissions is essential to keep global temperature rise from breaching the critical 1.5 degrees C threshold, in addition to steep cuts in carbon dioxide. Despite the urgency to address these pollutants, however, methane emissions continue to rise globally, with 2020 seeing the highest atmospheric concentration of methane ever. Recent reports, such as the Global Methane Assessment and the Intergovernmental Panel on Climate Change’s Sixth Assessment Report, also underscore the need for fast action to reduce methane.
The good news is that acting on methane comes with tremendous benefits, helping to limit near-term temperature rise and improve air quality, leading to better public health outcomes and improved food security. These actions can often be implemented at zero or low cost, providing significant economic benefits for governments and companies. In fact, in several cases, the actions reap cost savings after the initial investments are paid off. Many of the mitigation measures are also readily-available across all major methane emitting sectors — energy, agriculture and waste — providing an excellent solution for governments to meet climate and development goals.
Why is Reducing Methane Emissions Important?
Methane is the second most abundant human-caused greenhouse gas (GHG), and is 86 times more powerful than carbon dioxide over 20 years in the atmosphere (34 times more powerful over 100 years). Because it exists for a relatively short time in the atmosphere, cutting methane provides a quick benefit in terms of limiting near-term temperature rise. Studies estimate that ambitious actions to reduce methane can avoid 0.3 degrees C of warming by 2050.
Reducing methane also helps to improve air quality, as it is a pre-cursor to ground-level ozone, a damaging air pollutant that harms human health and crop yields. Readily-available methane mitigation measures can also prevent more than 250,000 premature deaths and 26 million tons of crop losses annually.
How Can Methane Emissions be Reduced?
Twelve countries are responsible for around two-thirds of global methane emissions: China, Russia, India, the United States, Brazil, the European Union, Indonesia, Pakistan, Iran, Mexico, Australia and Nigeria.
Most human-caused methane emissions stem from three sectors — energy (35%), agriculture (40%) and waste (20%) — so a focus on action in these sectors can help to stave off immediate warming impacts.
The energy sector is responsible for more than a third of global methane emissions, with oil and gas contributing the lion’s share (around 14%). Methane emissions occur along the entire oil and gas supply chain, but especially from fugitive emissions from leaking equipment, system upsets, and deliberate flaring and venting.
Existing cost-effective solutions can help reduce emissions, including initiating leak detection and repair programs, implementing better technologies and operating practices, and capturing and utilizing methane that would otherwise be wasted.
The International Energy Agency estimates around 75% of total oil and gas methane emissions can be avoided using currently available technologies, with more than half of these reductions at zero net cost. But despite the clear economic case for sealing leaks, utilities often recoup the costs of leaked gas by passing them on to consumers. Voluntary coalitions are, however, coming together to work toward lowering methane emissions in the sector, such as the Oil and Gas Methane Partnership and the Oil and Gas Climate Initiative.
Agriculture is the largest contributor to global methane emissions, producing about 40% of these emissions, primarily from enteric fermentation (cow burps), rice cultivation and manure management.
Improved agricultural production practices — specifically focused on improving efficiency — can enhance livestock and crop yields, provide more income for farmers, while at the same time reduce methane emissions per unit output. In areas where emission reductions are more difficult to achieve, like enteric fermentation, groups such as the Agriculture Innovation Mission for Climate and the Global Research Alliance on Agricultural Greenhouse Gases are helping spur greater innovation and technology deployment.
Reducing food loss and waste is another important area. Roughly one third of all food produced is lost or wasted throughout the food supply chain, with agricultural production responsible for the greatest amount, exacerbating food insecurity in vulnerable nations. These losses are due to many factors, including spillage or degradation during production.
If counted as a country, food loss and waste would be the third largest source of GHG emissions after China and the United States. But food producers and consumers can take immediate steps to reduce food waste immediately — from improving inventory systems, changing food date labelling practices and better facilitating the sale or donation of perishable products.
Small shifts in diet choices, particularly away from beef, can also make an impact globally, both in terms of freeing up agricultural land and reducing methane emissions. However, meeting today’s announced pledge does not necessarily depend on these diet shifts, according to data in the Global Methane Assessment.
Municipal Solid Waste
The waste sector accounts for around 20% of global human-caused methane emissions. Luckily, cost-effective mitigation solutions do exist, with the greatest potential related to separating organics and recycling which can also create new jobs. Upstream avoidance of food loss and waste is also key.
Additionally, capturing landfill gas and generating energy will reduce methane emissions, displace other forms of fuels and create new streams of revenue. The EPA projects that landfill gas utilization will remain the cheapest solution to mitigate emissions in the waste sector, often implemented at zero net cost. However, projects require high upfront capital costs which can sometimes be a deterrent in poorer jurisdictions.
Which Countries are Already Committed to Reduce Methane?
Outside of the newly announced global pledge, several countries have taken on individual commitments to tackle methane. In the last two years, for example, Nigeria and Cote D’Ivoire have committed to reducing methane emissions from the oil and gas sector by 45% by 2025 and 60-75% by 2030. The European Union has adopted an economy-wide methane strategy, with its accompanying models indicating that the region will need to limit methane emissions by 35-37% by 2030 relative to 2005 to meet its overall climate commitment. New Zealand aims to reduce biogenic methane emissions by 10% by 2030, and 24-47% by 2050, both relative to 2017 levels.
What to Look Out for Next?
The announcement of a global pledge to reduce methane emissions represents an important step forward — the first time that countries will collectively commit to acting to address methane across all sectors of their economies. At the same time, several countries are also finalizing their updated national climate action plans (the nationally determined contributions), where ambitious commitments to address methane should also be included — helping to keep the Paris Agreement’s goals within reach and ensure a safer future for all.