Civil aviation contributes to ~4% of the total anthropogenic radiative forcing, including the effects from CO2, NOx, water vapor and persistent contrails/contrail cirrus. The climate impact of contrails is significant and large uncertainties exist due to sparse relative humidity measurements at cruise levels and modeling inadequacies. Furthermore, one most critical aspect, which limits the projections of aviation’s climate impact, is the vast weather-induced variability of the radiative effect of individual contrails. This is the quantity, BeCoM will predict better since the knowledge of the individual radiative forcing is the basis for avoiding just those contrails that dominant the overall climate impact. Once this is accurate, BeCoM will formulate adequate mitigation measures and develop policy-driven implementation schemes for non-CO2 emissions/climate effects. The goal of BeCoM is to largely reduce or eliminate the global mean contrail radiative forcing, hence a substantial reduction of aviation’s global warming effects to be achievable on a much shorter time horizon.
BeCoM comprises six specific objectives:
• Objective O1: enhance the routine measurements of atmospheric humidity at the cruise altitude.
• Objective O2: improve the treatment of ice supersaturation conditions in numerical weather prediction models.
• Objective O3: develop appropriate AI algorithms for data assimilation, contrail detection, contrails classification, and uncertainties of contrail prediction (WP3).
• Objective O4: minimize overall cost when implementing climate optimized trajectories.
• Objective O5: develop non-CO2-based measures to be applied for ATM strategies for climate impact mitigation.