How We Mitigate the Harms of Methane
A closer look at the potent greenhouse gas methane, and some current solutions and policies for reducing it.
On March 20, 2023, the Intergovernmental Panel on Climate Change (IPCC) released its sixth annual report detailing the current status of climate change, progress on reducing global warming, and future risks and changes to our world that may occur if we exceed 1.5°C+ warming.
Below are some of the main findings:
We’re currently at around 1.1°C of warming, with climate projections forecasting a likely increase in global warming of 3.2°C by 2100.
Greenhouse gas (GHG) emissions will lead to continued global warming in the near term, and it's likely we’ll reach 1.5°C between 2030 and 2035.
To keep with the 1.5°C limit, we need to reduce emissions at least 43% by 2030 compared to 2019 baseline levels, and at least 60% by 2035. We must make drastic changes before 2030 to achieve this goal.
The world needs to move away from burning fossil fuels, one of the largest contributors to climate change. While that obviously includes carbon, it’s equally relevant to activities that release methane - the GHG currently responsible for close to a third of all global warming.
Rate of Temperature Change in the US 1901-2021
Source: EPA
While there’s been a lot of discussions from companies, governments, and the media around reducing carbon emissions, which make up the majority of GHG emissions from a volume standpoint. By comparison, awareness of methane’s potency, harms, and importance is still emerging in our cultural consciousness, despite its prevalence in everything from natural gas fracking to food waste.
Reducing GHG emissions is vital to slowing down the effects of climate change, an effort that will continue to take time, (sustainable) energy, commitment, and in many cases, financial investment. Which makes it all the more important to pay close attention to methane.
What Is Methane?
Methane (CH₄) is the second most emitted GHG in our environment after carbon dioxide (CO2), at around 16% globally. According to the International Energy Agency (IEA), Methane is responsible for around 30% of the rise in global temperatures since the industrial revolution. It has a shorter lifespan in the atmosphere than CO2 (about 12 years), but roughly 80 times the potency. And, after 12 years in the atmosphere, methane can combine with oxygen to create more CO2. It also absorbs more energy, trapping additional heat in the atmosphere.
The comparative impact of methane is 28 times greater than CO2 over a 100-year period. Over a 20-year period, methane is 80 times more powerful than CO2.
Even though there’s less methane in the atmosphere than CO2, it’s an incredibly powerful and dangerous GHG from a global warming perspective. The Global Methane Assessment estimates that if we cut methane emissions by 45% by 2030, we can avoid warming by 0.3°C by the 2040s. While 0.3°C seems like a small number, reducing emissions by any amount will help reduce countless extreme and catastrophic climate events in our future. These emissions reductions could play a huge role in decelerating warming in the next 10 to 20 years.
But right now, we’re not trending in the right direction with reducing methane emissions. In 2022, global methane emissions didn’t slow down at all, and remain 2.5x higher than pre-industrial levels.
However, it’s not all bad news (yet). What’s promising is we currently have the technology and strategies to reduce human-generated methane emissions. We just need more commitment and action from companies, supported by smart government policymaking.
How Is Methane Emitted through Human Activities and What Are the Solutions?
Methane is emitted from both natural sources and human activities. The three largest sources of human-emitted methane are agriculture, energy, and landfill waste.
Sources of methane emissions:
Source: IEA
1. Agriculture
Causes
The raising of livestock such as cattle, sheep, and goats contributes to human-caused methane emissions. As the world’s population continues to grow and the global poverty rate declines, the demand for animal protein continues to increase. These animals produce methane as a by-product through enteric fermentation which is a natural part of their digestive process. Because these animals are domesticated for human use and consumption, methane from enteric fermentation is considered a part of human-caused emissions. As a result, there are a variety of different tactics — from regenerative land management methods to feedstock changes — aimed at reducing methan emissions from livestock
Rice paddy cultivation is another area of agriculture that contributes to methane emissions. Paddies are often flooded to promote rice growth, triggering methane-emitting bacteria to grow. These bacteria account for approximately 8% of human-caused methane emissions.
Solutions
One of the simplest, most effective solutions is for humans to reduce meat consumption, but data show that despite the increased availability of plant-based substitutes, this is unlikely to happen (at least near-term). There’s been progress cultivating lower-emission meat in labs, but we’re still a ways to go before it’s commercially available. The most realistic, short-term solution is improving animal feed to be more nutritious so livestock are healthier and emit less methane.
Solutions to reduce emissions from rice paddies are still under development. A lot of the current solutions can’t be implemented at scale. One example of reducing methane-emitting bacteria from flooding rice paddies is using the System of Rice Intensification (SRI) methodology. It’s been around for decades and it uses less water, thereby reducing methane emissions and increasing crop yield. Unfortunately, this methodology is quite labor intensive and only feasible on smaller paddies. Scientists and engineers are looking at ways to reduce the workload and increase the scale of SRI methods.
2. Energy
A second major source of methane is the value chain across the production, transportation, and distribution of oil and natural gas. One particularly covert source of methane emissions are leaks during storage and transportation that can also be detected using sensors, scanners, or infrared imaging.
Causes
One of the critical problems with methane leaks by oil and gas companies is we don’t event know the full extent of it. Analysis from the IEA states that global methane emissions may be underreported by about 70%. It’s a colorless, odorless gas, so without proper tracking and controls, it can leak into the atmosphere without detection. There are no laws, at least in the US, that require oil and gas companies to track methane leaks, and there’s currently no penalty for leaking methane.
Solutions
For starters, we should work as a society to speed the energy transition toward using less oil and gas, full stop. From there, technology to monitor and prevent methane emissions from the oil and gas are readily available and is easily accessible. These solutions include leak detection and emissions control devices and replacing parts of machinery that emit methane regularly.
It’s also cost-effective for oil and gas companies to reduce or capture methane leaks. Many of the solutions could be implemented without any additional costs.
Another way to track methane emissions is through technologies such as sensor-equipped aircrafts, satellites, and drones. These aren’t the most simple solutions to deploy, but they can be help determine abnormally high levels of methane - which could be caused by unknown leaks. According to Bloomberg Green, over 24 satellites that’ll track methane emissions will be in orbit by the end of 2023. The images captured by the satellites will help to determine which companies are responsible for these massive leaks.
A February 5th, 2023 methane observation from a NASA/JPC-Caltech EMIT instrument
Source: Bloomberg Green
Ultimately, what matters most is holding companies in the fossil fuel value chain accountable for leaks and negligence. We have the tools to catch and stop methane leaks — now we need laws and standards to enforce them (and penalize non-compliance).
3. Landfill Waste
Causes
When waste enters landfills it decomposes with the help of oxygen. Within a year of trash entering a landfill, methane-producing bacteria begin to grow. This bacteria serves an important biological function in helping waste decompose, but the negative consequence (i.e., byproduct) is the methane gas it releases into the environment.
Solutions
Again, we can get the most leverage shrinking the inputs: less waste, less methane emissions. Beyond that, instead of letting methane escape into the atmosphere, there are ways methane can be captured through extraction wells and piping. As methane rises to the top of landfills, it can be collected through pipes. The gas that’s captured can then be used for various energy projects including producing heat or generating electricity. It’s not zero emissions circularity, but it’s better to burn methane recovered from a landfill than frack that same amount of energy from natural gas. It’s estimated energy generated via methane recovery reduces GHG emissions 16-20% vs. fracking, possibly more, given the risk of methane leaks and other environmental harms.
Source: EPA
Are There Any Policies in Place to Curb Methane Emissions?
The Global Methane Pledge (GMP) was introduced in 2021 at COP26 for participants to take action to voluntarily reduce methane emissions globally by 30% by 2030 from 2020 levels. Currently, 150 countries have signed on to the pledge which accounts for almost 50% of global human-caused methane emissions, according to GMP.
Other voluntary pledges and initiatives include The Methane Guiding Principles and The Oil and Gas Methane Partnership, which both look to reduce emissions in the oil and gas industry, and The Climate and Clean Air Coalition, which looks to reduce short-lived climate pollutants like methane by working with governments, companies, and scientific institutions.
These pledges are a great start at targeting methane emissions but they’re still voluntary. To ensure methane emissions are reduced by at least 45% by 2030, we need more mandatory legislation. In the past two years, there’s been an increase in methane-related policies globally, and we hope to see this trend continued in 2023.
New Methane Policies and Measures
Source: IEA
One country that’s actively working to reduce its emissions in the near term is Canada, a country that’s also been busy implementing a lot of other sustainability laws and initiatives in recent years.
Canada’s Methane Reduction Strategy looks for ways to reduce methane emissions across all industries by 40-45% below 2005 levels by 2030 and net-zero by 2050. From 2015 to 2020, Canada increased its oil and gas consumption while its methane emissions decreased. It’s also proposed an amendment to an existing federal framework to reduce oil and gas methane emissions and achieve at least 75% emissions reduction by 2030 compared to its 2012 baseline. There are also requirements for provincial methane regulations to achieve the same or better reductions than federal reductions.
Last year, at COP27, the US announced stricter proposed guidelines to the EPA’s current Clean Air Act for reducing methane and other harmful gases in the atmosphere. The proposed guidelines include broader use of satellites and other devices capable of detecting large methane leaks, as well as a response program for stopping them. The final ruling from the EPA is expected to be released by the end of 2023.
Reducing methane emissions starting now and over the next two decades is a critical part of the global transition to a low-emissions economy. Because methane is such a powerful GHG, atmospheric reduction has a lot of leverage when it comes to slowing down global warming. It’s encouraging to see legislative progress towards reducing methane emissions, alongside other public and private-sector problem-solving, but it’s essential to step up the rigor, scale, and deployment of methane migitation strategies.
Key action items:
Reduce the uncertainty of global methane emissions levels in the oil and gas industry
Actively monitor methane leaks around the world with satellites and other technologies
Work on finding more accessible and cost-effective solutions for reducing methane emissions across the largest methane emitting industries
Address the pervasive consequences of methane in our food system, particularly industrial livestock farming and food waste
Implement more policies for countries and companies around tracking, measuring, and reducing methane emissions.
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