The climate impact of aviation is caused by both CO2 emissions and non-CO2 effects, which include, for example, contrails, and contrail-cirrus, formation of ozone (O3) or methane (CH4) depletion by nitrogen oxide emissions. Aviation can reduce its climate impact by reducing its CO2 emissions and also its non-CO2 effects. One way to implement such mitigation measures is to try to fly around regions in the atmosphere that are particularly sensitive to non-CO2 effects using alternative flight path planning.
In a case study for the European airspace within the SESAR Exploratory Research project ATM4E, initial estimates of climate impact functions on a day with high contrail formation showed significant potential savings for a reduction in climate impact. These are associated with only a small increase in fuel consumption (about 0.5%) and are due to a significant reduction in non-CO2 effects (Matthes et al., 2020). For such an optimisation, it was further shown that high savings potentials can be achieved by skilfully selecting the flights to be optimised, even if only about 25% of intra-European flights are rescheduled in terms of climate optimisation (Lührs et al., 2021).
Our project coordinator DLR as (Co-)Author of both studies has just published a recap, highlighting the key results.
Have a look