Methane emissions have long been overlooked in the conversation about climate change, but their impact on global warming is becoming increasingly concerning. Methane is a “short-lived climate forcer” (SLCF), meaning its effect is short-lived, about 12 years, but is particularly destructive. In fact, one ton of methane has about 80x the warming potential heat-trapping ability of a tonne of CO2. Experts further say that methane emissions are responsible for about 30% of today’s climate change. The gas also poses health hazards to people, which can be deadly. The trends of methane emissions in the U.S. and worldwide are heading in the wrong direction.
The good news is that there’s a growing recognition among the scientific and political communities that reducing methane is critical in fighting climate change. Cutting methane emissions is the fastest option we have to slow the pace of global warming right away, even as we decarbonize the world’s energy systems. It’s an opportunity we shouldn’t miss. So, how can we address the methane problem and mitigate or reduce its emissions?
Methane (CH4) is the second most abundant anthropogenic or human-related greenhouse gas (GHG) after CO2. As already explained, methane is a potentially destructive gas that has a more powerful near-term warming effect than CO2. As a result, methane emissions contributed to about ⅓ of the increase in today’s GHG warming since pre-industrial times. And it’s growing faster than at any other time ever since record-keeping started in the 1980s.
Apart from driving climate change, methane also poses acute and chronic hazards to human health. The gas is explosive within certain ranges, presenting a safety hazard for people living in places with high methane concentrations. These particularly include areas around oil and gas facilities, coal mines, and some agricultural settings. Methane is also the primary contributor to ground-level ozone, a.k.a. smog formation, another GHG and harmful air pollutant. It’s often linked to various public health impacts such as asthma, weakened lung function, and cardiovascular diseases. Alarmingly, exposure to smog causes 1 million premature deaths each year. A study found that reducing 1 million tons of methane emissions may lead to a reduction of 240 to 590 premature deaths worldwide. With these facts, it’s no surprise that individuals living near areas of high methane production have poorer health conditions and poorer quality of life.
Over the past 200 years, methane concentrations in the air have more than doubled mainly because of human activities. These emissions have gone up alarmingly, which scientists think may be the biggest threat to keep global temperatures below 1.5°C. There are two main culprits for releasing CH4 into the atmosphere – natural and anthropogenic sources. Natural sources are: wetlands that are poorly managed are the biggest natural source, releasing methane from microbial decomposing activities reservoirs and ponds with high organic matter and low oxygen levels Other small natural sources of CH4 emissions include oceans, sediments, wildfires, volcanoes, and termites. Anthropogenic sources are: Agriculture – livestock raising Energy – oil and gas systems, coal mining Waste management activities – landfills and wastewater treatment
The largest anthropogenic source is agriculture, responsible for about a quarter of total CH4 emissions. The energy sector follows closely, which includes emissions from coal, oil, natural gas, and biofuels. Emissions from waste are the third biggest anthropogenic source. According to the U.S. Environmental Protection Agency (EPA), about 50-65% of total methane emissions come from anthropogenic or human activities. The agency also reported that CH4 accounted for 12% of all anthropogenic emissions in the U.S.
Though CH4 emissions from oil and gas systems come second overall, they’re the largest industrial source of methane. That’s why President Joe Biden directed the EPA to issue regulations under the Clean Air Act to reduce the oil and gas industry’s methane emissions. The Biden administration has supercharged existing efforts by pouring billions to address the methane problem. The big effort, thus far, is to plug over 4 million abandoned and orphaned oil and gas (AOOG) wells spread across the 26 states. This well-plugging program is worth almost $5 billion under the Infrastructure Investment and Jobs Act.
Reducing methane emissions is the fastest option we have to slow the pace of global warming right away, even as we decarbonize the world’s energy systems. It’s an opportunity we shouldn’t miss.