The overall aim of ATM4E is to explore the scope for the potential reduction of air traffic environmental impacts in European airspace on climate, air quality, and noise through optimization of air traffic operations The project will integrate existing methodologies for assessment of the environmental impact of aviation, in order to evaluate the feasibility of environmentally-optimized flight operations to the European ATM network, including climate, air quality, and noise impacts. A preliminary modelling concept for climate-optimization has previously been developed for an FP7 European Project, (REACT4C). The ‘case-study’ approach of REACT4C will be built upon and extended to a multi-dimensional environmental impact assessment, to cover climate, air quality and noise, to better understand impacts in the European airspace. Different traffic scenarios (present-day and future) will be analysed to understand the extent to which environmentally-optimized flights based on multi-dimensional environmental criteria (assessment) would lead to changes in air traffic flows and create challenges for ATM. The findings of the project will be used to prepare a roadmap that is consistent with SESAR2020 principles and objectives, which would consider the necessary steps and actions that would need to be taken to ultimately introduce environmentally-optimized flight operations in European airspace.

Aviation contributes to about 5% of the total anthropogenic climate change when including non-CO2 effects, e.g., contrail formation and the impact of NOx emissions on ozone and methane. Among various non-CO2 effects, the contrail-cirrus radiative forcing is the largest (~2/3) with large uncertainties. The most critical affecting factor is the huge weather-induced variability of the radiative impact of individual contrails. This is the quantity, BeCoM will predict better since the knowledge of the individual radiative forcing is the basis for avoidance of just those contrails that contribute most to the overall climate impact. Once this is standard, it will be possible to formulate adequate mitigation measures and develop policy-driven implementation schemes. BeCoM will address the uncertainties related to the forecasting of persistent contrails and their weather-dependent individual radiative effects. BeCoM focuses on: 1) obtaining a larger and higher resolution database of relative humidity and ice supersaturation at cruise levels for assimilation into numerical weather prediction (NWP) models; 2) providing more adequate representation of ice clouds in their supersaturated environment in the NWP models; and 3) validation of the predictions to determine and reduce the remaining uncertainties of contrail forecasts. To facilitate the assimilation and validation process, BeCoM will develop a novel hybrid artificial intelligence algorithm. Based on the contrail prediction, BeCoM will develop a policy framework for effective contrail avoidance through a trajectory optimization approach. BeCoM will enable a better understanding of contrail’s climate impact and formulate recommendations on how to implement strategies to enable air traffic management to reduce aviation's climate impact. The BeCoM consortium builds on its knowledge and expertise covering a wide spectrum from atmospheric science and climate research to aviation operations research and policy development.

The main objective of REIVON is to investigate to what extent the CO2 emissions of global aviation can be reduced via an optimisation of aircraft size/range and flight network. The project will first identify the theoretical potentials for reducing CO2 emissions via optimised aircraft, network and frequency reductions. Hereby, three alternatives for an optimised global air transport system will be considered: 1) splitting long-haul flights into shorter legs; 2) reducing frequencies to the necessary minimum; and 3) a combination of 1 and 2. Moreover, REIVON will assess the impacts on stakeholders of an optimised global air transport system (ATS) and will analyse potential measures to establish such a system with optimised aircraft, network and frequency reductions. REIVON will make use of an integrated approach involving experts from multiple disciplines, including aircraft design and performance, airline fleet and network optimisation, aircraft emissions modelling, air traffic demand modelling as well as impact assessment on local and global level. The analytical steps are carried out in four technical work packages, and a fifth work package is involved with management. REIVON will use various databases and a range of state-of-the-art models and tools to support the analysis. The findings of REIVON will be documented in a number of scientific reports.