Climate impact assessment of varying cruise flight altitudes applying the CATS simulation approach

Abstract

The present paper describes a comprehensive assessment and modelling approach that was developed in the DLR project Climate compatible Air Transport System (CATS) with the goal to analyze different options to reduce the climate impact of aviation. The CATS simulation chain is applied to assess the climate impact reduction potential (via CO2, contrail-cirrus, H2O, NOx, ozone, methane, primary mode ozone) for the world fleet of a representative long-range aircraft operated on a global route network in the year 2006. The average temperature response (ATR) and the direct operating costs (DOC) are calculated for flights with varying cruise flight altitudes and speeds. The obtained results are expressed as relative changes with respect to the minimum DOC trajectory and assessed as cost-benefit ratio (ATR vs. DOC). The results are highlighted for a single route and transferred to the global route network, showing a large potential to reduce the climate impact of aviation for small to moderate increments on costs.