A climate deal reached Thursday by 191 nations will allow airlines to grow in the coming decades without increasing their greenhouse gas emissions, Bobby Magill reports for Climate Central.

The International Civil Aviation Organization will encourage airlines to purchase credits through global carbon markets to offset their emissions for flights starting in 2021. This plan, to be phased in over 14 years, will allow airlines to balance the emissions from commercial aircraft by purchasing credits that fund conservation measures including renewable power projects, energy efficiency measures, and cleaner cookstoves.

The United States and other countries that have volunteered to require their airlines to purchase offsets will kick off this plan, with other member countries joining in by 2027 and 2035.

As Magill reports, “Commercial airplanes are major emitters of the carbon dioxide contributing to climate change, accounting for 11 percent of all emissions from the global transportation sector. Those emissions are expected to grow by about 50 percent by mid-century as the demand for air travel increases worldwide.”