ANGEO Annales Geophysicae ANGEO 1432-0576 Copernicus GmbH Göttingen, Germany 10.5194/angeo-27-2407-2009 High resolution observations of turbulence in the troposphere and lower stratosphere over Gadanki Dutta G. 1 Ajay Kumar M. C. 2 Vinay Kumar P. 1 Rao P. V. 3 Bapiraju B. 4 Aleem Basha H. 1 Department of Physics, Anwarul-Uloom College, New Mallepally, Hyderabad, India Department of Physics, Vanjari Seethaiah Memorial College of Engg., Bandlaguda, Hyderabad, India Department of Physics, Vasavi College of Engg., Ibrahimbagh, Hyderabad, India Department of Physics, A. V. College, Domalguda, Hyderabad, India 11 06 2009 27 6 2407 2415 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.ann-geophys.net/27/2407/2009/angeo-27-2407-2009.html The full text article is available as a PDF file from http://www.ann-geophys.net/27/2407/2009/angeo-27-2407-2009.pdf

High resolution (150 m) wind measurements from 13–17 July 2004 by Mesosphere-Stratosphere-Troposphere (MST) radar and 15–16 July 2004 by Lower Atmospheric Wind Profiler (LAWP) have been used to study the time variation of turbulence intensity. Layers of higher turbulence are observed in the lower stratosphere on 15–16 July which give rise to mixing in the region. Enhancement in short-period gravity wave activity and turbulent layers are observed after 22:00 LT which could be due to a dry convection event that occurred at that time. The breakdown of the convectively generated high frequency waves seems to have given rise to the turbulence layers. Wind shear is found to be high above the easterly jet, but very poor correlation is observed between square of wind shear and turbulence parameters in the region. The heights of the turbulent layers in the lower stratosphere do not correlate with levels of minimum Richardson number. A monochromatic inertia gravity wave could be identified during 13–17 July 2004. A non-linear interaction between the waves of different scales as proposed by Hines (1992) might also be responsible for the breakdown and generation of turbulence layers.

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