Oil and gas wells in Lea County, New Mexico. Photographer: Mark Felix/Bloomberg

The Cheap and Easy Climate Fix That Can Cool the Planet Fast

October 6, 2021, 12:00 AM EDT

Let a molecule of carbon dioxide escape into the atmosphere, and it stays for centuries. There’s more than enough up there to smother the planet like a too-warm quilt, trapping heat within and weirding the weather. The damage will be felt for generations.

But CO₂ is only part of the patchwork of warming. Methane locks in far more heat in the short term and has been leaking just as relentlessly.

Note: Direct measurements began in 1984

Sources: U.S. Environmental Protection Agency; National Oceanic & Atmospheric Administration

The difference is that methane’s power fades faster, within just decades. If we stopped emissions today, almost all the methane in the atmospheric blanket would degrade within a lifetime.

Methane vs. Carbon Dioxide

Scientists use a metric called the Global Warming Potential to judge the potency of greenhouse gases.

The measure shows that over the first two decades methane traps 84 times as much heat as the same amount of CO₂.

Over a century, its warming power is 28 times that of CO₂. That’s why cutting methane has such a big pay off: the faster emissions fall, the more warming we avoid.

Year 0

0.1

0.2 pW

Note: Absolute Global Warming Potential (AGWP) is a model that describes heat trapped by a kilogram of gas over time. This radiative forcing is measured in watts per square meter per kilogram per year, and is represented here in picowatts. Global Warming Potential (GWP) is the ratio of the AGWP of methane and of CO₂.
Sources: Environmental Defense Fund; Intergovernmental Panel on Climate Change

That’s why the U.S. and the European Union have been pressing countries to make a methane-cutting pledge. If enough nations sign up and meet the target—reaching a 30% reduction from last year’s levels by the end of the decade—the global movement against methane could prove to be one of the crucial achievements of the COP26 climate talks taking place in November in Glasgow, Scotland.

From Bloomberg Green Issue Five. Read more

Methane vs. Carbon Dioxide

An atmospheric census would find 200 molecules of CO₂ for every one of methane. Yet methane has caused nearly a quarter of the world’s observed heating over the past two and a half centuries, while CO₂ accounts for only about half.

The difference comes down to atmospheric physics and molecular mechanics. Every day the sun pumps vast amounts of energy into the planet. Some of it is absorbed by the land and oceans at the Earth’s surface, but most is reflected back into the sky in the form of infrared radiation. It’s on that journey back into space that most of the heat gets trapped under the quilt of greenhouse gases. The CO₂ molecules number an astonishing 30 trillion trillion trillion trillion—that’s 30 followed by 36 zeros—all jiggling constantly while absorbing and reflecting infrared light.

Methane does the same, except that its molecular structure, consisting of a carbon atom surrounded by four hydrogen atoms, traps heat more effectively. But that molecular structure and elemental makeup also allows methane to break down faster. This process happens through its easy interaction with other gases, such as oxygen, through which it forms new compounds, including CO₂.

Major Sources

Historically speaking, most of the methane released by direct human action has come from rice production and raising cows, which belch the greenhouse gas in significant quantities. But over the past 50 years, leaky fossil fuel infrastructure, much of it tied to the rise of natural gas, has also grown to become a supersized contributor.

Note: Map shows IPCC sector emissions in 2018 fitted to a database of emissions sites. Areas are shaded by total emissions from all sources; where multiple sources exist, the source with highest emissions is indicated.

Sources: European Commission; Joint Research Centre; World Resources Institute

The good news is that we have the tools we need right now to stop a large chunk of those emissions. Research by the United Nations found that as much as 80% of measures to curb leaks from oil and gas operations can be implemented at no cost, and many may even result in savings. Virtually all methane leaks from the coal sector could be painlessly eliminated.

“A huge amount of methane leakage is happening in the oil and gas industry,” says Cat Abreu, founder and executive director of Destination Zero, which seeks to eliminate fugitive methane. “It’s very cheap to cut, and, in many cases, it’s a job creator.”

Note: Oil and gas companies’ existing plans to cut methane have been counted as economically feasible. Analysis uses baseline emissions scenario for 2030 by Höglund-Isaksson et al and assumes no further climate action.

Source: Ilissa B Ocko et al 2021 Environ. Res. Lett. 16 054042

The Quick Fixes

Tackling methane starts with the oil and gas industry, where up to 85% of methane emissions could be mitigated by 2030 using existing technology, according to a paper published in Environmental Research Letters last year. The gas has been leaking freely into the air for years from fossil fuel infrastructure, especially in major producing and consuming nations such as China, Russia and the U.S.

Sources: European Commission; Joint Research Centre; World Resources Institute

Even though lost methane is a product that companies can sell to heat homes and spin power-plant turbines, most put little effort into tracking down fugitive plumes. Efforts by the U.S. government to monitor leaks since 2014 haven’t nearly reflected the full scope of the climate damage.

Using satellite data, researchers from Harvard found that emissions from the Permian Basin in Texas and New Mexico over an 11-month period were twice government figures. Emissions in the state of Pennsylvania are at least 15% higher than previously thought, according to a study by scientists at Cornell.

Note: Map shows IPCC sector emissions in 2018 fitted to a database of emissions sites. Areas are shaded by total emissions from all sources, and where multiple sources exist the source with highest emissions is indicated.

Sources: European Commission; Joint Research Centre; World Resources Institute

The French satellite-analytics company Kayrros SAS estimates that the Permian basin has emitted more than 2 million tons of methane this year through September, equivalent to the annual emissions from at least 40 million passenger cars.

Until recently methane detection was more of a craft project than a science. Producers and regulators relied on crude techniques such as throwing a tarp over a pipe to see if it bubbled or sending workers out to inspect equipment. There are now a host of technologies to detect fugitive methane, from parsing satellite data to deploying drones and handheld infrared cameras. Once a leak is detected, plugging it isn’t that different from high-tech plumbing.

Regulations in many countries also require coal-mining companies to build infrastructure that recovers methane before it’s released. The gas is collected and burned to help power the plant’s operations, so the costs work out favorably in the end.

Waste

The trash piled up in the landfills doesn’t just release CO₂ when it decomposes. In the absence of oxygen, methane forms instead. The gas builds up inside the mountains of waste, eventually escaping to the surface. Large clouds of methane in cities from Buenos Aires to Lahore have been attributed to landfills.

“Landfills are pretty complicated facilities,” says Bram Maasakkers, a researcher at the Netherlands Institute for Space Research. Scientists estimate that about 10% of human-caused methane comes from landfills, he says, “but how good the data is varies across the world.”

A growing number of landfill operators are starting to capture methane at their sites, which can be used to fuel the plants and garbage trucks. The Environmental Research Letters study estimates that 80% of emissions from landfills could be mitigated by 2030 using existing technology. The other solution is to cut down on waste and recycle more trash instead of discarding it.

Agriculture

The largest source of methane comes from growing the crops and meat that feed the world. And those emissions are set to grow as the global population increases and developing countries get richer.

More than two-thirds of the world’s rice is grown by flooding fields that cover an area twice as large as France. Microbes in the waterlogged soil produce large quantities of methane.

Research in China, one of the biggest producers of rice, has found it’s possible to cut methane in half by draining water from rice paddies in the middle of the growing season. The process also increases rice yields and saves water. Other researchers, in India and the Philippines, have found new varieties of rice that can thrive in dry fields—though their yields don’t yet match those of widely grown varieties.

For the world’s 1.4 billion cows, the problem starts in the gut. The ruminants get help from bacteria to break down the hard-to-digest grasses they eat. The cost, however, is the production of methane as a byproduct.

Cutting these methane emissions is more challenging, but researchers are working on several potential solutions. One is to use special feed additives that help cows produce less methane. Cargill, the world’s largest agriculture company, is also urging suppliers to put special masks on cattle that would trap methane and convert it into CO₂.

A dairy cow in Hertfordshire, England, wears a methane-reducing mask developed by Zelp Ltd. Photographer: Hollie Adams/Bloomberg

In the fight against global warming, methane has flown under the radar for too long. But there’s increasing recognition that tackling the invisible, odorless gas is one of the easiest, cheapest, and most feasible ways to make a real difference in slowing climate change. It’s the rare climate problem with a fix that can be felt by those alive right now, not their great-grandchildren.

“The world will continue to warm as long as CO₂ is being pumped into the atmosphere,” concluded an August editorial in the scientific journal Nature. But curbing methane will help buy “humanity a bit more time to do what needs to be done.”

Editors: Sharon Chen and Aaron Rutkoff

Sources: Emission Locations: Emissions Database for Global Atmospheric Research (Edgar) v6.0, Crippa et al. and Joint Research Centre. Maps show IPCC sector emissions in 2018 fitted to a database of emissions sites. Areas are shaded by total emissions from all sources; where multiple sources exist the source with highest emissions is indicated. Data for waste includes emissions from landfills, solid waste incineration, and wastewater. Data for agriculture includes emissions from livestock, rice cultivation, and soil management. Shares of Global Emissions from Climate Watch. 2020. Washington, DC: World Resources Institute

The Cheap and Easy Climate Fix That Can Cool the Planet Fast

Methane Surge

Read more methane leak stories:

Methane vs. Carbon Dioxide

Major Sources

Where Methane Comes From

Start Cutting Here

The Quick Fixes

China, Russia and the U.S. Are Super-Emitters

U.S. Emissions

Leak Detection

Waste

China, Indonesia, and the U.S. Are Super-Emitters

Agriculture

India, China and Brazil Are Super-Emitters

60% of Emissions From Rice Could Be Mitigated by 2030

31% of Emissions From Livestock Could Be Cut by 2030