Aircraft Black Carbon Particle Number Emissions – A New Predictive Method and Uncertainty Analysis
Roger Teoh1, Marc E.J. Stettler1, Arnab Majumdar1 and Ulrich Schumann2
1Department of Civil and Environmental Engineering, Imperial College London, London, SW7 2AZ, UK
2Deutsches Zentrum für Luft- und Raumfahrt, Institute of Atmospheric Physics, 82234 Oberpfaffenhofen, Germany
Black Carbon (BC) particle number emissions from aircraft jet engines contribute to contrail formation, which have a significant and short-lived climate impact. Previous studies have shown that the number of contrail ice particles is dependent on the number of BC particles emitted by aircraft. This research proposes a new method to estimate BC particle number emissions per mass of fuel (EIn) for global civil aviation based on theory of the morphology of fractal aggregates
The new method is applied to an aircraft activity sample dataset from the Aviation Environmental Design Tool (AEDT). Quantitative analysis suggests the average cruise BC EIn to be around 1.2×1015 kg-1, 40% higher than previous estimates. A higher BC EIn estimate relative to previous methodologies implies that young contrail properties will have a smaller ice particle diameter and larger optical depth. As a result, contrail lifetime and its magnitude of radiative forcing is expected to increase.