Atmospheric Measurement Techniques Discussions www.atmos-meas-tech-discuss.net 1867-8610 3 4 2010 10.5194/amtd-3-3455-2010 http://www.atmos-meas-tech-discuss.net/3/3455/2010/ http://www.atmos-meas-tech-discuss.net/3/3455/2010/amtd-3-3455-2010.html http://www.atmos-meas-tech-discuss.net/3/3455/2010/amtd-3-3455-2010.pdf 3455 3487 2010-08-18 Fine-scale turbulence soundings in the stratosphere with the new balloon-borne instrument LITOS A. Theuerkauf theuerkauf@iap-kborn.de M. Gerding F.-J. Lübken Leibniz-Institute of Atmospheric Physics at the Rostock University, Kühlungsborn, Germany We have developed a new compact balloon payload called LITOS (Leibniz-Institute Turbulence Observations in the Stratosphere) for high resolution wind turbulence soundings up to 35 km altitude. The wind measurements are performed applying a constant temperature anemometer (CTA) with a vertical resolution of ~2.5 mm, i.e. 2 kHz sampling rate at 5 m/s ascent speed. Thereby, for the first time, it is possible to study the entire turbulence spectrum down to the viscous subrange in the stratosphere. Including telemetry, housekeeping, batteries and recovery unit the payload weighs less than 5 kg and can be launched at any radiosonde station. Since autumn 2007 LITOS has been successfully launched several times from the Leibniz-Institute of Atmospheric Physics (IAP) in Kühlungsborn, Germany (54° N, 12° E). Two additional soundings were carried out in 2008 and 2009 at Kiruna, Sweden (67° N, 21° E) as part of the BEXUS program (Balloon-borne EXperiments for University Students). We describe here the basic principle of CTA measurements and prove the validity of this method in the stratosphere. First case studies allow a clear distinction between non-turbulent layers and turbulent layers with a thickness of some tens of meters. 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