Properties and Processing of Aviation Exhaust Aerosol at Cruise Altitude Observed from the IAGOS-CARIBIC Flying Laboratory
Christoph Mahnke (Forschungszentrum Jülich)
Rita Gomes (Forschungszentrum Jülich)
Ulrich Bundke (Forschungszentrum Jülich)
Marcel Berg (Forschungszentrum Jülich)
Helmut Ziereis (Deutsches Zentrum für Luft- und Raumfahrt (DLR))
Monica Sharma (Deutsches Zentrum für Luft- und Raumfahrt (DLR), TU Delft - Aerospace Engineering)
Mattia Righi (Deutsches Zentrum für Luft- und Raumfahrt (DLR))
Johannes Hendricks (Deutsches Zentrum für Luft- und Raumfahrt (DLR))
Andreas Zahn (Karlsruhe Institut für Technologie)
undefined More Authors (External organisation)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
The characteristics of aviation-induced aerosol, its processing, and effects on cirrus clouds and climate are still associated with large uncertainties. Properties of aviation-induced aerosol, however, are crucially needed for the assessment of aviation’s climate impacts today and in the future. We identified more than 1100 aircraft plume encounters during passenger aircraft flights of the IAGOS-CARIBIC Flying Laboratory from July 2018 to March 2020. The aerosol properties inside aircraft plumes were similar, independent of the altitude (i.e., upper troposphere, tropopause region, and lowermost stratosphere). The exhaust aerosol was found to be mostly externally mixed compared to the internally mixed background aerosol, even at a plume age of 1 to 3 h. No enhancement of accumulation mode particles (diameter >250 nm) could be detected inside the aircraft plumes. Particle number emission indices (EIs) deduced from the observations in aged plumes are in the same range as values reported from engine certifications. This finding, together with the observed external mixing state inside the plumes, indicates that the aviation exhaust aerosol almost remains in its emission state during plume expansion. It also reveals that the particle number EIs used in global models are within the range of the EIs measured in aged plumes.
help_outline