References

AMT

Atmospheric Measurement Techniques

AMT

Atmos. Meas. Tech.

1867-8548

Copernicus Publications

Göttingen, Germany

10.5194/amt-6-697-2013

On the effect of moisture on the detection of tropospheric turbulence from in situ measurements

Wilson

¹ Luce

² Hashiguchi

https://orcid.org/0000-0001-8033-0955

³ Shiotani

https://orcid.org/0000-0001-5844-4032

³ Dalaudier

UPMC Univ Paris 06, LATMOS-IPSL, UMR8190, CNRS/INSU, 75005, Paris, France

Univ. du Sud Toulon-Var, 83957, La Garde Cedex, France

Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Japan

14 03 2013

6 3 697 702

2013

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://amt.copernicus.org/articles/6/697/2013/amt-6-697-2013.html

The full text article is available as a PDF file from https://amt.copernicus.org/articles/6/697/2013/amt-6-697-2013.pdf

The present paper addresses the detection of turbulence based on the Thorpe (1977) method applied to an atmosphere where saturation of water vapor occurs. The detection method proposed by Thorpe relies on the sorting in ascending order of a measured profile of a variable conserved through adiabatic processes, (e.g. potential temperature). For saturated air, the reordering should be applied to a moist-conservative potential temperature, θ<sub>m</sub>, which is analogous to potential temperature for a dry (subsaturated) atmosphere. Here, θ<sub>m</sub> is estimated from the Brunt–Väisälä frequency derived by Lalas and Einaudi (1974) in a saturated atmosphere. The application to balloon data shows that the effective turbulent fraction of the troposphere can dramatically increase when saturation is taken into account. Preliminary results of comparisons with data simultaneously collected from the VHF Middle and Upper atmosphere radar (MUR, Japan) seem to give credence to the proposed approach.

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