The need for rapid methane mitigation

While the link between carbon dioxide (CO₂) emissions and rising temperatures is widely known, the role of methane as a driver of climate change generally receives less public attention. Methane concentrations in the atmosphere are increasing rapidly, caused to an overwhelming degree by emissions from human activity. They are currently at 260% of pre-industrial levels, totaling between 350 and 390 million tonnes annually. To curb global warming in the next few decades, CO₂ reduction needs to be complemented by rapid and effective measures for mitigating methane and other climate pollutants.

Following on the 2021 report Global Methane Assessment: Benefits and Costs of Mitigating Methane Emissions by the Climate and Clean Air Coalition (CCAC), a platform under the umbrella of the United Nations Environment Programme (UNEP), the newly released 2030 Baseline Report takes stock of current efforts and projects anthropogenic methane emissions under various baseline scenarios. Baseline emissions scenarios assume the implementation of existing policies and commitments, but do not include additional mitigation action.

Agriculture, waste management, fossil fuel extraction, and open biomass burning are the primary sources of anthropogenic methane. The report highlights that global baseline methane emissions will continue to rise without serious efforts. By 2030, they are projected to increase by 5-13% compared with 2020 levels, with the largest increase expected in the agricultural sector. Least-cost scenarios for limiting warming to 1.5°C require methane emissions reductions of about 60% from fossil fuels, 30-35% from waste, and 20-25% from agriculture by 2030, relative to 2020 emissions.

Thus, making this a reality requires comprehensive, targeted, and, above all, socially equitable policies:

“For fossil fuel sectors, we need a regulatory framework to ensure existing technologies are implemented and used by the industry. For the waste and agricultural sectors, solutions must consider the socioeconomic implications of change to make sure poor people and people from disadvantaged groups are part of the solutions. This ensures that changes do not aggravate existing challenges for these groups,” says Lena Höglund-Isaksson, a coauthor of the report and a senior researcher in the IIASA Pollution Management Research Group.

At the 2021 Conference of Parties (COP26) in Glasgow, the Global Methane Pledge (GMP) was launched, complementing broader CO₂ efforts, which by themselves are not enough to align with 1.5°C scenarios. Through the GMP, participants agreed to take collective action to reduce anthropogenic methane emissions by at least 30% from 2020 levels by 2030. As of August 2022, over 120 countries have joined the pledge.

Achieving the GMP targets would reduce warming by at least 0.2°C between 2040 and 2070, in addition to preventing roughly 6 million premature deaths annually due to ozone exposure, avoiding the loss of nearly 580 million tons of yield losses, avoiding costs of 500 billion US$ due to non-mortality health impacts, forestry, and agriculture, as well as preventing the loss of 1,600 billion work hours due to heat exposure. In sum, nearly 85% of targeted measures have benefits that outweigh the costs.

However, the report makes clear that while current policies and measures represent a step in the right direction, more needs to be done. The GMP covers only half of the world’s anthropogenic methane emissions, and only a fraction of countries have proposed explicit measures to achieve their mitigation targets. More signatory countries need to be brought on board, and current commitments need to be expanded.

“We must achieve significant abatement across all sectors, and it must happen now. The rapid implementation of methane emission control is one of the very few options left to keep the world at manageable levels of global warming in the next few decades,” Höglund-Isaksson concludes.

Reference

United Nations Environment Programme/Climate and Clean Air Coalition (2022). Global Methane Assessment: 2030 Baseline Report. Nairobi. https://www.ccacoalition.org/en/resources/global-methane-assessment-2030-baseline-report