Sources and Effects of Methane Emissions on Climate Change

An estimated one-third of the world’s methane emissions are from oil and gas operations. These emissions originate at different points along the oil and gas supply chain, including equipment leaks, system upsets, and deliberate flaring. Fortunately, several low-cost, low-energy mitigation solutions are available to curb the emissions. Leak detection and repair programs, improved technologies, and improved operating practices are practical and cost-effective ways to reduce methane emissions.

Methane has a relatively short atmospheric lifetime of about 12 years, whereas CO₂ has a long lifespan of over one hundred years. Despite its lower half-life, methane is more effective at trapping solar energy and other forms of radiation than CO₂. It is estimated that cutting methane emissions could significantly reduce the rate of warming of the planet in the near term, increase crop yields, and prevent premature death.

Sources

Methane is an important greenhouse gas, contributing to 16% of the total radiative forcing from long-lived greenhouse gases. Methane emissions occur from various sources, including fossil fuel production, landfills, rice cultivation, and the digestion of ruminants. Of the total emissions, about 30% are caused by fossil fuel use, which can be controlled with current technologies. In addition to human activities, agricultural fields and wetlands also contribute to methane emissions.

While methane emissions are becoming more common worldwide, a study recently published by NASA scientists indicates that methane is a significant contributor to climate change. The researchers say that methane production contributes to climate change faster than carbon dioxide. Burning natural gas produces half the CO₂ as coal, but this environmental benefit is wholly lost when methane leaks are present. Furthermore, methane pollution contributes to ground-level ozone and is linked to adverse health effects. It also impacts frontline communities and people of color more than any other group.

Impact

The Committee on Methane Emissions and Climate Change of the National Academies of Sciences, Engineering, and Medicine researched the methods used to measure and inventory methane emissions from the energy sector. The committee examined the strengths and weaknesses of different inventory approaches and products, including methane attribution and modeling. It also identified key uncertainties associated with anthropogenic methane emissions. This report will help decision-makers understand the importance of methane emissions and climate change and how to reduce them.

Methane is a potent greenhouse gas with about 28 times the global warming potential of carbon dioxide. It accounts for many underground fossil fuel reservoirs, making it a significant global issue. It can leak out from various sources, including the complex natural gas infrastructure web. Improving the measurement of methane emissions is vital for practical mitigation efforts. The problem with methane and climate change is that the effects of this greenhouse gas are not immediately apparent.

Reducing emissions

A recent study found that reducing methane emissions could help reduce the likelihood of climate tipping points. Among the benefits of reducing methane emissions are significant health benefits and economic gains, including reducing lost labor hours due to extreme heat.

In addition to limiting methane emissions, environmental groups are calling for regulating gas and oil leaks. Under the current rules, methane emissions from these sources are limited to new wells built after 2015. Most oil and gas wells in the U.S. are unregulated and are small, low-producing wells. According to Fred Krupp, the Environmental Defense Fund president, methane emissions should be reduced through a national regulatory framework that regulates leaks and flaring from marginal wells.

Reducing emissions from agriculture

Methane emissions from agriculture are an enormous source of climate change, accounting for up to 40% of all human-caused emissions. The agriculture sector has an excellent opportunity to cut emissions by 30% by 2030 and a half by 2050. The most obvious step toward reducing agricultural methane emissions is to reduce the number of ruminant animals which produce methane during digestion. Ruminants produce more methane than any other sector, and the sector contributes nearly 70% of the country’s emissions.

Methane is the second-most powerful greenhouse gas after carbon dioxide. Its effect on the planet is much faster than carbon dioxide, accounting for around 30% of the total warming in the past century. It also decays very quickly, so cutting methane emissions can immediately affect limiting global temperatures in the near term. According to studies, cutting methane emissions can prevent almost 0.3 degrees of warming by 2050.