See our press release on this letter: English / Deutsch

Aviation may have contributed as much as 4.9% to global radiative forcing in 2005 and its carbon dioxide emissions could grow by up to 360% between 2000 and 2050. In 2016, the International Civil Aviation Organization adopted a global scheme requiring airline operators to offset increases in carbon dioxide emissions from international flights above 2020 levels. Here we show that the scheme will only compensate for the emissions increase if robust criteria for the eligibility of offset credits are adopted.