Climate-Optimized Trajectories and Robust Mitigation Potential: Flying ATM4E

Abstract

Aviation can reduce its climate impact by controlling its CO2-emission and non-CO2effects,e.g., aviation-induced contrail-cirrus and ozone caused by nitrogen oxide emissions. One option isthe implementation of operational measures that aim to avoid those atmospheric regions that are inparticular sensitive to non-CO2aviation effects, e.g., where persistent contrails form. The quantitativeestimates of mitigation potentials of such climate-optimized aircraft trajectories are required,when working towards sustainable aviation. The results are presented from a comprehensivemodelling approach when aiming to identify such climate-optimized aircraft trajectories. The overallconcept relies on a multi-dimensional environmental change function concept, which is capable ofproviding climate impact information to air traffic management (ATM). Estimates on overall climateimpact reduction from a one-day case study are presented that rely on the best estimate for climateimpact information. Specific weather situation that day, containing regions with high contrail impact,results in a potential reduction of total climate impact, by more than 40%, when considering CO2andnon-CO2effects, associated with an increase of fuel by about 0.5%. The climate impact reduction perindividual alternative trajectory shows a strong variation and, hence, also the mitigation potentialfor an analyzed city pair, depending on atmospheric characteristics along the flight corridor as wellas flight altitude. The robustness of proposed climate-optimized trajectories is assessed by usinga range of different climate metrics. A more sustainable ATM needs to integrate comprehensiveenvironmental impacts and associated forecast uncertainties into route optimization in order toidentify robust eco-efficient trajectories.