“There is probably nothing we can do that will have a greater effect on lowering maximum temperatures over the next several decades than removing methane,” says Rob jackson, researcher at Stanford and co-author of the two studies.
Methane is relatively rare: carbon dioxide is around 200 times more concentrated in the atmosphere. Nonetheless, it has contributed around 30% of total global warming to date, or around 0.5 ˚C, according to a recent study. report of the United Nations Intergovernmental Panel on Climate Change. Although its lifespan in the atmosphere is only about 10 years, over short periods it is about 86 times more potent as a greenhouse gas than carbon dioxide.
“The methane will disappear, but in the meantime it will cause problems”, says Vaishali Naik, Atmospheric Specialist for the United States National Oceanic and Atmospheric Administration.
Because of its short lifespan, if methane emissions were reduced today, air levels would drop rapidly. In a recent United Nations Environment Program report on methane that Naik co-wrote, researchers estimated that a 45% reduction in methane emissions today could reduce warming by 0.28 ° C by mid-century, keeping the world under target. of less than 1.5 ° C warming from pre-industrial levels, as defined by the Paris Agreement.
About two-thirds of those reductions could be achieved using readily available solutions, Naik says. This includes plugging leaking natural gas wells and decreasing reliance on coal mines, which release methane stored below the earth’s surface and produced when plant material turns into coal. Reducing some emissions is probably cheaper and easier than expanding removal technology, she says.
But to keep warming below 1.5 ° C, methane emissions from industries such as agriculture would also have to be reduced, which could be more difficult as the population grows.