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| Titel |
Aircraft type influence on contrail properties |
| VerfasserIn |
P. Jessberger, C. Voigt, U. Schumann, Ingo Sölch, H. Schlager, S. Kaufmann, A. Petzold, D. Schäuble, J.-F. Gayet |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 23 ; Nr. 13, no. 23 (2013-12-11), S.11965-11984 |
| Datensatznummer |
250085868
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| Publikation (Nr.) |
 copernicus.org/acp-13-11965-2013.pdf |
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| Zusammenfassung |
The investigation of the impact of aircraft parameters on contrail properties
helps to better understand the climate impact from aviation. Yet, in
observations, it is a challenge to separate aircraft and meteorological
influences on contrail formation. During the CONCERT campaign in November
2008, contrails from 3 Airbus passenger aircraft of types A319-111,
A340-311 and A380-841 were probed at cruise under similar meteorological conditions
with in situ instruments on board DLR research aircraft Falcon. Within the
2 min-old contrails detected near ice saturation, we find similar effective
diameters Deff (5.2–5.9 μm), but differences in
particle number densities nice (162–235 cm−3) and in
vertical contrail extensions (120–290 m), resulting in large differences in
contrail optical depths τ at 550 nm (0.25–0.94). Hence larger
aircraft produce optically thicker contrails.
Based on the observations, we apply the EULAG-LCM model with explicit ice
microphysics and, in addition, the Contrail and Cirrus Prediction (CoCiP)
model to calculate the aircraft type impact on young contrails under
identical meteorological conditions. The observed increase in τ for
heavier aircraft is confirmed by the models, yet for generally smaller τ.
CoCiP model results suggest that the aircraft dependence of
climate-relevant contrail properties persists during contrail lifetime,
adding importance to aircraft-dependent model initialization. We finally
derive an analytical relationship between contrail, aircraft and
meteorological parameters. Near ice saturation, contrail width
× τ scales linearly with the fuel flow rate, as confirmed by
observations. For higher relative humidity with respect to ice (RHI), the
analytical relationship suggests a non-linear increase in the form
(RHI-12/3. Summarized, our combined results could help to more
accurately assess the climate impact from aviation using an
aircraft-dependent contrail parameterization. |
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