Case study of wave breaking with high-resolution turbulence measurements with LITOS and WRF simulations

Measurements of turbulent energy dissipation rates obtained from wind fluctuations observed with the balloon-borne instrument LITOS (Leibniz-Institute Turbulence Observations in the Stratosphere) are combined with simulations with the Weather Research and Forecasting (WRF) model to study the breakdo...

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Bibliographic Details
Published in:Atmospheric Chemistry and Physics
Main Authors: Schneider, Andreas, Wagner, Johannes, Söder, Jens, Gerding, Michael, Lübken, Franz-Josef
Format: Other Non-Article Part of Journal/Newspaper
Language:German
Published: Copernicus Publications 2017
Subjects:
Online Access:https://elib.dlr.de/113781/
https://elib.dlr.de/113781/1/Case-study-of-wave-breaking-Schneider-AtmChemPhys.pdf
https://www.atmos-chem-phys.net/17/7941/2017/
https://doi.org/10.5194/acp-17-7941-2017
Description
Summary:Measurements of turbulent energy dissipation rates obtained from wind fluctuations observed with the balloon-borne instrument LITOS (Leibniz-Institute Turbulence Observations in the Stratosphere) are combined with simulations with the Weather Research and Forecasting (WRF) model to study the breakdown of waves into turbulence. One flight from Kiruna (68° N, 21° E) and two flights from Kühlungsborn (54° N, 12° E) are analysed. Dissipation rates are of the order of 0. 1 mW kg−1 (∼ 0.01 K d−1) in the troposphere and in the stratosphere below 15 km, increasing in distinct layers by about 2 orders of magnitude. For one flight covering the stratosphere up to ∼ 28 km, the measurement shows nearly no turbulence at all above 15 km. Another flight features a patch with highly increased dissipation directly below the tropopause, collocated with strong wind shear and wave filtering conditions. In general, small or even negative Richardson numbers are affirmed to be a sufficient condition for increased dissipation.