Record Rise in Global Methane Levels Threatens ‘Habitable Climate’

While 155 countries have committed to reducing methane emissions by 30 percent by 2030 under the Global Methane Pledge, new research reveals that the world’s methane emissions have been rising at a record pace over the last five years.

At least two-thirds of methane emissions produced each year come from human activities like agriculture, fossil fuels, landfills and other waste, the Stanford Report said.

In a new perspective article published in Environmental Research Letters, the researchers warn this dire pattern “cannot continue if we are to maintain a habitable climate.” The article was published with corresponding figures in Earth System Science Data.

Both papers were produced by the Global Carbon Project, an initiative that tracks global greenhouse gas emissions and is chaired by Rob Jackson, a Stanford University scientist.

Concentrations of methane in the atmosphere have grown to more than 2.6 times what they were during pre-industrial times and the highest the planet has seen in 800,000-plus years.

“Right now, the goals of the Global Methane Pledge seem as distant as a desert oasis,” said Jackson, lead author of the paper published in Environmental Research Letters. “We all hope they aren’t a mirage.”

If humans continue on the current emissions path, the planet will experience global heating from three to five degrees Celsius by 2100, according to the Stanford Report.

Methane is produced by both human sources and natural sources such as wetlands. It is a short-lived and highly potent gas that heats the atmosphere almost 90 times more quickly than carbon during the first two decades after it is released. This means it is important to target it in the short-term to reduce the pace of global heating.

The new estimates show that total yearly methane emissions have risen by 20 percent — 61 million tons — in the last two decades.

These increases are mostly driven by rising emissions from oil and gas, coal mining, sheep and cattle ranching and food and other organic waste decomposing in landfills.

“Only the European Union and possibly Australia appear to have decreased methane emissions from human activities over the past two decades,” said Marielle Saunois of France’s Université Paris-Saclay, lead author of the paper published in Earth System Science Data. “The largest regional increases have come from China and southeast Asia.”

Nearly 400 million tons — 65 percent — of methane emissions worldwide were from human activities in 2020, with waste and agriculture contributing twice as many emissions as the fossil fuel industry.

The researchers said anthropogenic emissions continued to climb through at least 2023.

Scientists with the Global Carbon Project made a key change in their latest calculations of methane sources and sinks across the globe, including soils and forests that remove and sequester methane from Earth’s atmosphere.

Previously, the scientists had categorized the methane produced by lakes, ponds, rivers and wetlands as “natural,” but this methane budget is the first to try and estimate the increasing emissions from these sources that are caused by human activities and influences.

“Emissions from reservoirs behind dams are as much a direct human source as methane emissions from a cow or an oil and gas field,” Jackson said in the Stanford Report. Jackson’s new book, Into the Clear Blue Sky: The Path to Restoring Our Atmosphere, was published by Scribner in July.

The researchers estimate that roughly a third of recent freshwater and wetland methane emissions were influenced by anthropogenic factors like reservoirs, wastewater, fertilizer runoff, rising temperatures and land use.

“The world has reached the threshold of a 1.5 °C increase in global average surface temperature and is only beginning to experience the full consequences,” the researchers wrote in Environmental Research Letters.