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| Titel |
Scaling Analysis of Temperature and Liquid Water Content in the Marine Boundary Layer Clouds during POST |
| VerfasserIn |
Yong-Feng Ma, Szymon Malinowski, Katarzyna Karpińska, Hermann Gerber, Wojciech Kumala |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250143566
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| Publikation (Nr.) |
 EGU/EGU2017-7299.pdf |
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| Zusammenfassung |
| We have analyzed the scaling behaviour of marine boundary layer (MBL) clouds using
high-resolution (∼5.5 cm) temperature (T) and liquid water content (LWC) series from
airborne measurements collected over Pacific Ocean during the Physics of Stratocumulus Top
(POST) research campaign in summer of 2008. As an extension of the past studies for
scale-invariant properties of MBL clouds, we studied variability of scaling exponents with
height. We divided the horizontal flight segments (within MBL) and the inclined flight
segments (across the cloud top region) into several layers and sublayers, and used power
spectra and structure functions to estimate the scale-invariant regimes for each layer. The
results show that both T and LWC within MBL have two distinct scaling regimes: the first
one displays scale-invariance over a range from 1∼5 m to at least 7 km, and the
second one goes from about 0.1∼1 m to 1∼5 m. For the large scales (r > 1 ∼ 5 m),
turbulence in MBL is multifractal, while scale break and scaling exponents (e.g., β, ζ1,
ζ2, ζ∞, H1 and C1) vary with height, most significantly in the cloud top region.
The bifractal analysis shows that the standard scale-invariant stochastic models are
not enough to represent the vertical structure of atmospheric turbulence in MBL,
and suggests the existence of three turbulence regimes: near the surface, in the
middle of boundary layer and in the cloud top region, which should be distinguished. |
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