Continuing Rise of Methane Emissions Worrying Top Scientists

One of the most troubling aspects of the fight against global warming is the failure to curb the continuing rise of methane emissions.

Methane is one of the most potent greenhouse gases and the second largest contributor to global warming after carbon dioxide. It has a much stronger warming effect than CO2, as it traps more heat in the atmosphere, but remains for a much shorter period of time.

Two thirds of methane emissions come from human activities, according to the latest research for the Global Methane Budget, an international collaboration that estimates sources and methane “sinks” around the world. But the lead author of the study has said methane levels have been accelerating annually and have shown no “hint of a decline”.

ALSO SEE: China’s Billion-Ton Coal Expansion Plan Sparks Methane Fears

Rob Jackson, a professor in Earth system science at Stanford University and lead author of the Environmental Research Letters paper, has been quoted as saying he was “surprised and disappointed” by the extent of the ongoing rise in methane concentration.

“Methane levels are not just increasing, they’re increasing faster than they were [in the past]… it’s incompatible with not just 1.5C, but 2C – and has us heading towards 3C if it continues,” he told Carbon Brief in a report published on Tuesday.

One third of methane emissions come from natural sources, notably wetlands, such as bogs and salt marshes. And the bulk of methane caused by human activity come from agriculture (40%), fossil fuels (34%) and waste or landfills (19%).

Methane emissions in 2020 in teragrams (equivalent to millions of tonnes) of methane per year. The findings are based on bottom-up and top-down methods for methane sources and sinks that are human-caused (orange), natural (green) and a mix of the two (hatched). Source: Jackson et al. (2024)

ESA blames China’s coal use, Middle East oil & gas

The European Space Agency (ESA), which plans to send up more satellites to monitor methane emissions, said in a report on Tuesday that the latest methane research findings were “worrying”.

It noted that the top five emitters of anthropogenic methane in 2022 were China (16%), India (9%), the USA (7%), Brazil (6%), and Russia (5%), and said that “emissions from coal exploitation in China and oil and gas extraction in the Middle East are major contributors” to the methane crisis.

The report said while there were currently no technologies capable of directly removing methane from the atmosphere, strategies for reducing methane emissions in the fossil fuel and waste sectors were imperative.

The Copernicus Sentinel-5P satellite was playing a key role, it said, in “providing daily global coverage at relatively high-resolution observations of atmospheric methane concentrations,” which were used in a study to determine emissions changes from 2018 till 2023.

“This satellite data can also help identify methane hotspots, especially as a component of tiered observing approaches to quantify ‘super-emitter’ point sources when combined with data from higher resolution sensors such as GHGSat.”

Tropical wetlands may be expanding

Last year, methane emissions were reported to have surged from wetlands in South America, South Asia, Southeast Asia and Africa during 2020-2021, which can range from tropical mangroves to salt marshes.

Global warming had caused shifts in rainfall patterns, which suggested that these areas were getting bigger, wetter and warmer. But permafrost peatlands in higher latitudes could also be a factor in the methane rise, scientists said.

Jackson, the Stanford professor, suggested that was possible. He told Carbon Brief: “There’s something happening in the tropics, and there’s a lot of concern that increased tropical emissions may be something of a tipping point for methane. If tropical emissions begin to increase from natural wetlands, we have no way to mitigate those emissions.

“I think there’s enough evidence to say that natural systems are contributing to the increase in recent years, but I don’t think we could attribute all that increase to natural systems,” he said.

Other factors behind the surge may be an increase in methane from both agricultural and fossil fuel sources. Indeed, climate change may be causing methane sinks to decline and methane to break down in the atmosphere more slowly, it said.

While scientists try to determine what is happening, Jackson was frank: “We are miles from where we should be,” he said.

Greater funding and mitigation work needed

A key concern is that while most countries have vowed to reduce emissions, only a small number have set quantitative targets or timelines for implementing mitigation measures.

And less than 2% of global climate finance – just over $10 billion – was targeted at methane mitigation in 2019-20, according to an analysis by the Climate Policy Initiative, a non-profit group. It said they needed 10 times that amount to get closer to 1.5C of warming.

A third of methane emissions come from the energy sector, from leaks at different stages of oil, natural gas and coal operations and the burning of gas during oil extraction, according to the International Energy Agency (IEA).

But currently only about 100 companies – a third of oil and gas producers – are part of the Oil and Gas Methane Partnership 2.0 organized by the UN Environment Programme.

An IEA report says “targeted actions” like repairing leaks to reduce methane emissions from fossil fuel production and use are crucial to keeping warming to no more than 1.5C.

However, policies aiming to reduce fossil methane emissions have been less stringent than those for waste, according to a 2023 study.

As our teachers often said: ‘Greater effort needed.’