Climate assessment of single flights: Deduction of route specific equivalent CO₂ emissions

Climate impact of anthropogenic activities is more and more of public concern. But while CO₂ emissions are accounted in emissions trading and mitigation plans, emissions of non-CO₂ components contributing to climate change receive much less attention. One of the anthropogenic emission sectors, where non-CO₂ effects play an important part, is aviation. Hence, for a quantitative estimate of total aviation climate impact, assessments need to comprise both CO₂ and non-CO₂ effects (e.g., water vapor, nitrogen dioxide, and contrails), instead of calculating and providing only CO₂ impacts. However, while a calculation of CO₂ effects relies directly on fuel consumption, for non-CO₂ effects detailed information on aircraft trajectory, engine emissions, and ambient atmospheric conditions are required. As often such comprehensive information is not available for all aircraft movements, a simplified calculation method is required to calculate non-CO₂ impacts. In our study, we introduce a simple calculation method which allows quantifying climate assessment relying on mission parameters, involving distance and geographic flight region. We present a systematic analysis of simulated climate impact from more than 1000 city pairs with an Airbus A330-200 aircraft depending on the flight distance and flight region to derive simplified but still realistic representation of the non-CO₂ climate effects. These new formulas much better represent the climate impact of non-CO2 effects compared to a constant CO₂ multiplier. The mean square error decrease from 1.18 for a constant factor down to 0.24 for distance dependent factors and can be reduced even further to 0.19 for a distance and latitude dependent factor.