Reducing plane clouds can help climate - study

"Persistent" cloud or contrail is created when an aeroplane is flying through cold and humid airspace and its exhaust mixes with cold air at high altitudes

Reducing the long plumes of cloud caused by aeroplanes could help reduce by 40%, the impact aviation has on heating the planet, according to researchers.

Aviation experts warned the clouds - known as contrails or condensation trails - could act as a "blanket" in the sky, contributing to raised temperatures on the ground.

The University of Cambridge study found one in 30 flight miles generated a "persistent" cloud when flying through particularly cold and humid airspace and suggests planes avoid these by rerouting at key points in flight paths.

Prof Rob Miller, director of the university's Whittle Laboratory, said: "Aviation stands at a pivotal moment, much like the automotive industry in the late 2000s."

The Cambridge University experts say reducing the contrails could reduce by 40% the impact of aviation on heating the planet

The "persistent" cloud created when an aeroplane is flying through cold and humid airspace is caused by its exhaust fumes mixing with cold air at high altitudes.

The joint report with the Cambridge Institute for Sustainability Leadership called for international trials - or "living labs" - to be created, to test the impact of its recommendation, ready for take-up by the airline industry within five years.

The industry should would work with atmospheric forecasts and data to reroute flights where necessary, researchers said.

Aviation was a major contributor to climate change, accounting for 2-3% of global CO2 emissions and about 5% once the non-CO2 climate impacts were included, said Prof Miller.

Despite ambitious pledges from governments and industry, the sector remains significantly off-course in its efforts to achieve net zero by 2050, the report added

Other recommendations included unlocking "systems-wide efficiency gains" across the existing aviation sector to halve the total amount of fuel burnt in 2050, reforming policies on sustainable aviation fuels and more research into hydrogen-powered aircraft.

Currently, the climate impacts of the aviation sector are predicted to double by 2050, the report says.