Latest BEIS data shows that carbon dioxide emissions from UK departing flights in 2015 were 34.5 Mt. DfT’s October 2017 aviation forecasts give CO2 emissions from UK departing flights of between 36.6 and 45.7Mt in 2030; between 36.3 and 45.1Mt in 2040; and between 35.0 and 44.3Mt in 2050, depending on demand scenario and airport capacity options.
The Government will set out its strategic approach to the aviation sector in a series of consultations leading to the publication of a new Aviation Strategy for the UK. The Strategy will consider what the best approach and combination of policy measures are to ensure we effectively address carbon emissions from aviation.
The 3 Mt figure quoted from page 85 of the Clean Growth Strategy concerns emissions from transport not including domestic or international aviation and shipping.