Methane: the ugly, bad, and the goodNovember 3, 2022
Many Americans begin the morning with breakfast, usually cooked over the stove. Possibly eggs, pancakes, or toast from bread baked in the oven. Our lives take energy, whether it is the morning cup of coffee or the natural gas we use to cook our meals, the energy has to come from somewhere. One energy source has found itself in the crosshairs of the climate crisis, from both the solution and problem aisles.
Though natural gas has become a popular energy source in recent years, scientists are beginning to examine the impact of methane emissions on global temperature rise.
“The lifetime half-life of methane in the atmosphere is about ten to twelve years and that could lead to a temperature rise of five to eight degrees centigrade for the whole planet,” explained Sir David King in a recent press briefing. He is the founding chair of the Center for Climate Repair at Cambridge University.
As methane levels in the atmosphere rise faster and faster, the impact of this greenhouse gas is becoming more understood. As a potent greenhouse gas, it contributes to approximately 80 times more warming than carbon dioxide. This warming occurs within the first ten years of the gas’s lifetime in the atmosphere. Because of this, methane removal has become a focus of research in order to help reduce the risk of drastic global temperature rise in the next 20 years.
“The increases [of release] in the last two years of 16 and 17 parts per billion are the biggest in the past 40 years and we don’t completely understand why,” explained Dr. Robert Jackson, a Stanford University professor and chair of the Global Carbon Project. This sharp increase in methane emissions is not fully understood.
Naturally occurring methane storage sources, known as methane sinks or natural accumulation zones, have been slowing, meaning less methane is being sequestered naturally. These zones are part of the methane cycle. Bacteria and other microbes are the largest sources of natural methane sinks.
Removing methane from the atmosphere has been identified as a possible technological solution to reducing the immediate warming the planet may face over the next two decades.
But where does it come from?
Methane is a naturally occurring gas. With a chemical makeup of one carbon molecule and four hydrogen molecules, CH4, methane is a product of anaerobic fermentation. It bubbles up from the muds of bogs and marshes. It comes from livestock. It is highly concentrated in the permafrost.
“The arctic circle region has been heating up about four times the rate of the planet’s average over the last 20 years,” said Sir David King, a chemist and academic. This increased rate of warming has already elevated arctic temperatures by three degrees Celsius, above the normal average.
Aside from the permafrost, the largest source of methane emissions is agriculture, notably the production of beef. Known as enteric fermentation, the breakdown of grasses in a cattle’s digestive tract creates methane. Across Nevada, enteric fermentation accounts for about 1.2 million metric tons (MMT) of carbon dioxide equivalent or CO2e.
CO2e is the number of metric tons of CO2 with the same warming potential as one metric ton of another greenhouse gas.
Our trash creates another form of enteric fermentation. Landfills are a major source of methane emissions. However, out at the Lockwood Nevada landfill, operated by Waste Management, mitigation efforts have been put into place to reduce emissions.
“We utilize a series of gas extraction wells that are drilled into the landfill at various locations to collect the landfill gas,” explained Paul Rosynsky, the communications specialist for Waste Management.
At the Lockwood landfill, the gas is used to generate energy. While this does convert methane into CO2 and water, it creates about 3.2 megawatts of electricity a day. This is enough to power about 2,000 homes across the region.
The methane is captured through a network of wells that are placed into the landfill. This collection system also allows for the use of methane to power a portion of the trash collection vehicle fleet.
“Our team of engineers and technicians monitors methane gas emissions throughout the landfill to make sure our gas extraction wells are adequately collecting the landfill gas and conveying it to the engines and flare,” explained Rosynsky about the challenges of collecting methane from such an unusual source.
The landfill is under constant review, and new gas wells are added to ensure as much methane can be captured as possible.
“In Nevada, Waste Management is working in several communities to promote organics recycling where available and frequently encourages customers to create backyard composting areas,” said Rosynsky.
Capturing methane in lieu of letting it ascend into the atmosphere has been identified as a realistic way to reduce a short-term rise in global temperatures. However, some scientists and engineers believe there is a more drastic step necessary to slow the steady rise in average global temperatures over the next 20 years.
Removal, abatement, and transition
“We’ve run out of time to simply mitigate,” said Dr. Robert Jackson. He talked in a virtual press conference about methane removal and believes it is time to pursue research for methane removal.
Pursuing all mitigation measures “could slow the global-mean rate of near-term decadal warming by around 30%,” according to Dr. Ilissa B Ocko, a senior climate scientist with the Environmental Defense Fund. She was the lead author of a peer-reviewed paper that examined the need to rapidly begin methane mitigation.
The paper explained points to studies that find methane mitigation can slow the rate of warming and sea level rise and is essential to achieving long-term temperatures target, such as the 1.5 C goal outlined in the 2015 Paris Agreement. “Direct methane mitigation measures are more effective at reducing emissions than reductions,” the paper explained.
Methane removal is the process of oxidizing methane to carbon dioxide and water vapor. Naturally occurring, scientists want to begin catalyzing the process in order to reduce the warming rate.
“By converting methane to carbon dioxide we are simply speeding up the natural process,” explained Jackson. The oxidation of methane does not require any storage and is feasible with today’s technology. Though there are limitations, establishing a network of methane oxidation points is one step in reducing the upward spiral of global average temperatures.
The next viable step is something we can all take, reduce our use and reliance on natural gas.
Natural gas is a ubiquitous vapor. It powers school buses, generates electricity, and helps millions of people bake that perfect loaf of sourdough bread. Yet it is causing concern for many scientists as a potent greenhouse gas.
Gas appliances have recently been identified as a source of the same pollutants as car exhaust. This increases the risk of childhood asthma and other respiratory problems. There are over an estimated 40 million gas stoves in homes across the country. Another source of combustion is gas furnaces.
Another study found that even when gas stoves were not in use, they released methane and harmful nitrogen oxides in the home. The Global Methane Assessment found that methane is “a key ingredient in the formation of ground-level ozone (smog), a powerful climate forcer and dangerous air pollutant.” The report highlighted that a 45% reduction would prevent at least 260,000 premature deaths and 775,000 asthma-related hospital visits and reduce agricultural losses.
This situates natural gas as a health risk to the public. Removing gas appliances from households is a small step but a mighty method of mitigating methane emissions. A stride that provides the average person power to fight the climate crisis.
The impacts of methane reduction will resonate globally and can be enacted by the individual.
The Inflation Reduction Act (IRA) President Joe Biden signed in August included measures for households to begin transitioning away from natural gas. The IRA includes a provision that provides a rebate for the purchase of an electric stove. It also assists in doing away with gas furnaces and replacing home heating systems with heat pumps.
These wonders of technology convert cool air into warm air in the winter and hot air into cool air in the summer. The technology is also available in water heaters, dryers, and other heat-related appliances. When used with renewable electricity sources, such as wind and solar, methane emissions will be drastically reduced.
While there are other methods of reducing your greenhouse gas emissions, modernizing the home is a powerful individual action that can start the societal shift needed to avert the climate crisis.
As methane emissions continue to increase rapidly, the removal of methane is a likely step in averting a drastic global rise in temperatures over the next 20 years. With the signing of the IRA, addressing climate change as an individual is now less daunting.
This story was first published with the Sierra Nevada Ally.