Global airlines are setting up a task force to deal with non-carbon dioxide (CO2) emissions, stepping up efforts to tackle cloudy streaks formed by aircraft known as contrails, an environmental threat that until now has taken a backseat to carbon pollution in the response to global warming.

The move comes as the International Air Transport Association (IATA), representing some 300 major airlines, is preparing to discuss the warming effect of contrails for the first time at its annual meeting in Istanbul next week.