The United Nations' International Civil Aviation
Organization has approved a plan to reduce and offset carbon emissions on
international flights, the first such global agreement for the aviation
industry. The plan
calls for airlines to cap emissions on international flights at 2020 levels
beginning in 2021 by either reducing emissions or offsetting them with carbon
credits. Participation is voluntary until 2027, at which point it becomes
mandatory. So far, 65 states have signed up to participate during the voluntary
phase, according to the International Air Transport Association.