It describes a present and near future characterized by compounding of extreme climate events, including wildfires, droughts, and heat waves. Although striking, the key messages in this report are not new; they build on years of similar research and findings from the IPCC and other reputable international bodies.
However, this report – the IPCC’s sixth assessment report on the physical science basis of climate change – draws special attention to the issue of methane, a greenhouse gas that is a more powerful contributor to climate change than carbon dioxide on a ton-for-ton basis. According to the new IPCC report, methane emissions in 2019 were the highest of any year in the past 800,000 years.
Methane has a relatively brief duration in the atmosphere. In theory, if you were to cease all emissions of methane today, within two decades there would be no more methane in the atmosphere to trap radiation. This is different from carbon dioxide, which exists for thousands of years in the atmosphere. Reducing carbon dioxide emissions today is important, but even so we will still experience the climatic effects associated with carbon dioxide emitted thousands of years ago. Compared with carbon dioxide, reducing methane offers quick returns for climate change mitigation.
Reducing methane emissions is not only a critical step in slowing global temperature increases, it offers numerous other benefits.
Methane, a combustible gas, provides energy. If you capture methane at the source (e.g., a landfill or oil production facility), you can use it to generate electricity or provide heat for industrial uses. For the parts of the world that are energy insecure, methane capture and utilization projects can be key to achieving consistent and reliable power. For example, a network of underground pipes can collect the gas at landfills, and pumps move the gas to a collection station for processing. For livestock, another major methane source, one technique isto gather manure and put it into digester systems that decompose the material and create methane as a biproduct.
Methane is money. In addition to being an energy source, methane can be used as an industrial feedstock and for other commercial purposes. For example, methane gas collected from landfills can be combusted to generate electricity or heat, or purified and injected into natural gas pipelines. Allowing the gas to vent to the atmosphere is comparable to allowing an oil gusher to continue spewing the valuable resource after a blowout.
Emitted methane damages health. Methane itself is not an air pollutant, but in the atmosphere it reacts with other agents to form tropospheric ozone, a hazardous air pollutant and a component of smog.
Mitigating Methane Across Countries: A Complex Problem Requiring Coordination
As awareness of the importance of methane rises, we are seeing increased attention to the need for mitigation. Companies are voluntarily adopting practices to promote better management of methane in existing infrastructure, researchers are studying better methods to measure and prevent methane emissions from natural sources, and project developers are deploying innovative techniques to productively use recovered methane.
Nevertheless, these actions are often piecemeal, disassociated, and insufficient. Despite growing awareness about methane, many significant barriers remain. Methane recovery and utilization technologies remain expensive and are not globally accessible. Financial institutions are generally unfamiliar with the financial viability of methane capture projects and are not supportive. Governments interested in addressing methane at a national scale lack information and best practices to support the design and implementation of effective policies.
To reduce methane emissions at the pace needed to slow climate change in the near term, we need coordinated global efforts to institute methane mitigation policies. Coordination at the international level on policy best practices will send important signals to project developers and facility owners who seek to capitalize on methane recovery technology and financial institutions that struggle with perceptions that methane capture and use is unproven.
As the global community prepares for the coming UN Climate Change Conference of the Parties (COP26) meetings in Glasgow, there will be discussions about how countries can use their updated nationally determined contributions (NDCs) to advance national methane mitigation. The NDCs, essentially country-specific emissions reduction targets required under the Paris Agreement, are a key tool for coordinating action to address climate change. But patchwork country-specific commitments will not likely be sufficient. It will be interesting to see how prominently the issue of methane mitigation is featured in the main and side events at the COP. If the issue is not taken up with urgency in Glasgow, it is difficult to envision a scenario in which we are able to avoid exceeding critical temperature thresholds in the near future.