Targeting methane “ultra-emitters” could cheaply slow climate change

ON FEBRUARY 15TH 2018 a gas well blew up in Ohio’s Belmont county. Flying overhead shortly before 1pm, a state highway-patrol helicopter captured images of a column of flames and a billowing plume of soot and gases rising high into the sky from the rolling hills. Although the flames were soon put out, the bust wellhead was not patched up for 20 days. A subsequent study using satellite data calculated that during that time, some 58,000 tonnes of methane was released, equivalent to one-quarter of what Ohio’s entire oil-and-gas infrastructure reportedly produces every year and more than the annual methane emissions of similar fossil-fuel infrastructure in most European countries.Methane is a colourless, odourless greenhouse gas that makes up the bulk of the natural gas burned to heat homes, cook food and generate electricity. It is also the second largest driver of global warming after carbon dioxide, responsible for at least one-quarter of the rise in global average temperatures since the Industrial Revolution. Once emitted, methane molecules degrade in around a decade so they do not pile up in the atmosphere in the same way as carbon dioxide, which can persist for hundreds of years.