Deep cuts in methane emissions, including from the fossil fuel industry, are urgently needed to slow the rate of global warming and keep it beneath a threshold agreed by world leaders, according to a UN report due to be released next week.
Governments are increasingly looking at methane emissions as they seek solutions to cap warming at 1.5 degrees Celsius above pre-industrial levels, the target nearly 200 countries agreed to under the 2015 Paris Agreement on climate change.
Methane has a much higher heat-trapping potential compared to carbon dioxide and it breaks down in the atmosphere much more quickly than CO2, meaning cutting methane emissions can have a climate impact sooner.
“Urgent steps must be taken to reduce methane emissions this decade,” according to a summary of the Global Methane Assessment, seen by Reuters ahead of its publication by the United Nations Environment Programme and the Climate & Clean Air Coalition next week.
The report summary, whose findings were first published by The New York Times, includes contributions from more than 20 scientists and experts.
It said currently available measures could reduce human-caused methane emissions by up to 45%, or 180 million tonnes a year by 2030. That would avoid nearly 0.3 degree Celsius of global warming by the 2040s, it said.
“There’s no chance whatsoever to meet our climate targets if we don’t deal with the methane emissions that this report highlights,” said Jonathan Banks, international director for methane at the non-profit Clean Air Task Force, which is part of the organisation that released the report but did not author it.
“Methane provides an opportunity for a win on climate change in the very near term,” he said.
Cheapest emission cuts are in oil and gas
The report said the fossil fuel sector has the biggest potential to slash methane emissions this decade. Fossil fuels account for 35% of human-caused methane emissions, while agriculture contributes 40% and waste such as landfills accounts for 20%, it said.
Climate scientists say the cheapest emission cuts are in the oil and gas industry, where methane is vented after oil extraction or can leak from gas pipelines.
“Around 80% of no-cost actions come from the oil and gas industry. In each of the scenarios analysed; nearly a third of that would come from top oil and gas producers meeting their agreed upon targets to reduce upstream leakage,” says the Environmental Defense Fund, a US-based campaign group.
The study comes as the European Union and United States are both drafting their own regulations to tackle methane emissions, due to be unveiled later this year as they strive to meet new domestic targets to reduce greenhouse gas emissions by 2030. The US Senate will this week vote on legislation to reverse Trump-era rollbacks of methane rules.
“We have calculated that if we manage to reduce by 50% the global emission of man-made methane, then we could reduce the temperature rise by 0.18°C. So this is going to be important when we are going to get to 1.5°C maximum,” said an EU official as the European Commission presented its methane strategy last year.
Earlier this month, the US National Oceanic and Atmospheric Administration reported that current methane levels in the atmosphere are the highest on record.
In a paper published this week in the journal Environmental Research Letters said a rapid, full-scale effort to reduce methane emissions from the oil and gas industry, large-scale agriculture and other human sources could slow the worldwide rate of warming by as much as 30%.
[Edited by Frédéric Simon]