n.84 Rising methane: A new climate challenge
In 2007, the amount of methane in the atmosphere (CH4) began to rise after a 7-year period of near-zero growth (1). Recent research shows that a second step change occurred in 2014 (2). From 2014 to at least the end of 2018, the amount of CH4 in the atmosphere increased at nearly double the rate observed since 2007 (see the figure). Because CH4 is a potent greenhouse gas, rising atmospheric CH4 presents a major challenge to achieving the goals set out in the Paris Agreement, an international consensus to limit temperature increase to 2°C or, if possible, to 1.5°C above preindustrial levels.