The struggle to put a carbon price on a flight

annoy green activists as much as air travel. Planes account for a sliver of total carbon-dioxide emissions— roughly 2.5%—but unlike heating, other transport and electricity, journeys on them are often luxuries not essentials. Air travel has also largely escaped carbon pricing, which covers a quarter of all emissions. Change is in the air, however. Since the start of last year, a -backed scheme has required airlines to offset emissions above a baseline by buying credits. On December 6th the decided to bring airlines deeper into its carbon-trading scheme. These are steps in the right direction, even if they are unlikely to bring about fast enough decarbonisation for Europe to hit its goal of a net-zero aviation industry by 2050.