In addition to carbon dioxide, air traffic operation affects the climate through other emissions and atmospheric processes, such as the formation of ozone and contrail cirrus. The climate impact of these non-CO2 effects is strongly dependent on the emission location (in particular cruise...

The report analyzes, by looking back at existing compliance systems in the EU, Alberta, Australia, Colombia and Japan, the conditions under which offsets can add value to the compliance system without undermining its environmental integrity. The compliance system’s climate ambition as well as...