A surge in methane emissions, a greenhouse gas with a global warming potential 24 times higher than CO2, is threatening worldwide efforts to tackle global warming, according to an editorial published on Monday 12 December by an international scientific team.
The editorial, published in the scientific review, Environmental Research Letters, on the first anniversary of the Paris climate agreement has the effect of putting the cat among the pigeons. The scientists report a rise in methane emissions unprecedented in two decades, jeopardising the chances of keeping the rise in temperature to under two degrees Celsius, which was already a “very difficult” target to meet, the scientists say.
The team of scientists which coordinated the research to establish a global overview reports that methane concentrations in the air began to surge around 2007 and grew precipitously in 2014 and 2015. In that two-year period, concentrations increased tenfold, shooting up by ten or more parts per billion annually. The reason for the spike is still unclear but the cause may by emissions from agricultural sources mainly around the tropics – potentially from farm sites like rice paddies and cattle pastures (methane is a by-product of the cattle digestive process). Exploration will be continued. (Original version in French by Aminata Niang)