CIVIL aviation accounts for perhaps only 2% of manmade carbon emissions. Add in other pollutants, such as contrails and nitrous oxide, and the industry’s overall contribution to climate change might be twice that figure. That may not seem much. But the sector is growing rapidly. Since the 1970s, global air traffic has doubled in size about every 15 years. Rising prosperity in developing countries and massive backlogs of aircraft orders means that the growth will continue for decades. Without regulation, the world’s airlines could quickly choke the skies.

Last week, the International Civil Aviation Organisation (ICAO), a United Nations agency, announced a framework for mandatory carbon-offsetting on all international flights. The agreement was backed by 65 countries, which between them account for 86.5% of international flight operations.

International flights, unlike domestic ones, were exempt from last year’s Paris Agreement on climate change. This new tentative accord seeks...Continue reading