Improvements in aircraft design, air traffic management and fuel efficiency could reduce US passenger airline emissions by as much as 50% by 2050 compared to 2012 levels, with little or no cost to the airlines, reports a paper published online this week in Nature Climate Change.
Global air transport emissions are currently rising by 3.6% a year. International governments and airline associations have started exploring strategies for mitigating carbon dioxide (CO2) emissions, but the associated economic benefits and costs are not well understood.
Andreas Schafer and colleagues looked at 21 options to curb the emissions from the US domestic aviation sector, the world’s largest air transportation system. They focus on narrow-body aircraft (that have 100-189 seats), which generate a majority of the sector’s CO2 emissions.
They find that improvements to aircraft design could be the main driver of emission reductions, with open rotor engines, all-carbon fibre airframes and more aerodynamic wing designs making planes more efficient. Air traffic management and the airlines’ own operational efficiency could contribute about 20% to the emissions reduction, with new, synthetic fuels from biomass accounting for a further 10% of the reduction. They report that airlines could achieve at least three-quarters of the potential emissions reduction by implementing only the options that are cost effective.
The authors note that the sector’s overall emissions are largely dependent on fleet size. If the number of planes grows at a rate below 2% per year (the current anticipated growth rate is 1.5% per year), emissions could be lower in 2050 compared to 2012. A growth rate higher than 2.6% per year, however, would outpace the entire range of assessed emissions reduction options.