Greenhouse gases from flights, million tonnes

Fuel used per tonne-km carried (2000 = 100)

What it means: greenhouse gases from the fuel burned by all flights departing UK airports, by any airline, and by domestic flights within the UK (1.2 million tonnes of the total). Emissions rise and fall with the fuel burned. International flights are not counted in the UK’s official carbon budgets until 2033 but are reported alongside them. The per-passenger figure is a rough guide worked out on this page: total emissions divided by half the 292.3 million passengers counted at UK airports, since each passenger is counted on departure and arrival. Long-haul flights produce far more per passenger than short ones. The second chart shows how efficiently air transport uses fuel: the energy used for each tonne carried one kilometre, counting each passenger as a fixed weight and adding freight. It was 82.4 in 2024 (2000 = 100), so flights carry about a fifth more for the same fuel than in 2000. It jumped in 2020 and 2021 when planes flew nearly empty during Covid. No official figure gives CO2 per passenger-kilometre for all flights from the UK: passenger-kilometres are only published for UK airlines, while the emissions cover every airline. The effect of emissions at high altitude, which adds to warming, is not included. Shown for context.

Source: DESNZ, final UK greenhouse gas emissions statistics, tables 1.2 and 5.1; passengers from DfT aviation statistics, table AVI0101; fuel per tonne-km from DESNZ, Energy Consumption in the UK 2026, table I2.