Atmospheric Methane Levels Higher than Ever Before
Atmospheric methane levels have reached an all-time high, with annual atmospheric methane increases recorded in 2019 being the second highest since the National Oceanic and Atmospheric Administration (NOAA) began collecting this data in 1983.
Atmospheric methane levels reached around 1,875 parts per billion (ppb) in 2019, an increase from the 1,866 ppb recorded in 2018, according to preliminary data presented by NOAA, which is still pending recalibration and quality control measures.
While methane is a relatively short-lived in the atmosphere compared to carbon dioxide, which hangs around for much longer, it is much more effective at trapping heat emitted by the sun, making it 28 times more potent in terms of its warming capacity. Consequently, methane is an important greenhouse gas that plays a key role in climate warming, and it can gravely undermine our efforts to reduce global warming if we focus solely on reducing carbon dioxide emissions.
â€œHere we are. Itâ€™s 2020, and itâ€™s not only not dropping. Itâ€™s not level. In fact, itâ€™s one of the fastest growth rates weâ€™ve seen in the last 20 years,â€ said Drew Shindell, a climate scientist at Duke University, in an interview with Scientific American.
The primary sources of methane emissions include natural sources such as wetlands, as well as anthropogenic sources such as livestock, landfills, and oil and gas extraction sites. While humans cannot do much to curb emissions from natural sources, we can take steps to reduce methane from human sources.
According to Shindell, the easiest solution to reduce methane emissions is to reduce the amount of methane released from oil and gas extraction sites. Natural gas comprising mostly of methane is very prone to escaping from wells during extraction. This can be addressed in two ways: 1) by burning it, which converts the methane into CO2; or 2) by simply finding and plugging any leaks.
Another option is for companies to install equipment to help them recover methane-rich natural gas before it escapes into the atmosphere. This gas can be sold to help offset costs associated with recovery equipment. It is estimated that implementing measures such as this could help oil and gas companies reduce their methane emissions by 45% at no extra cost.
However, Shindell points out that despite these incentives, many companies remain skeptical of investing in recovery equipment and would rather invest the limited capital they have on establishing new wells, which are more likely to yield higher returns.
Atmospheric methane levels remained relatively flat between the late 1990s and early 2000s, but after 2006, they began to steadily increase, largely due to the increase in oil and gas production. The recent rise in global methane levels jeopardizes goals set out by the Paris Climate Agreement, which is based on the assumption that methane levels would remain level and eventually drop off as countries began meeting their climate targets. Climate experts believe that is essential to curb methane emissions in order to limit climate warming over the short term, which will buy us valuable time to implement climate adaptation measures that will enable us to cope in the long term.
â€œYou see the benefits in the first decade or two that you make cuts. You see fewer people dying from heat waves. You see less powerful storms and all of the stuff that comes from climate change,â€ Shindell said. â€œAs long as weâ€™re still using fossil fuels, we should at least not be leaking out lots and lots of methane.â€