White cloud streaks high up in the sky are one of the ways you can tell a plane has been overhead. And although they can form striking patterns in the sky, these contrails and the cirrus clouds they induce, impact climate change, possibly greater than the effect from CO2 emissions.

During 2013 we enabled savings of 59,000 tonnes of fuel, thereby avoiding 190,000 tonnes of CO2 from being released into the atmosphere. It was our best ever year ever in terms of savings.