Characteristics of atmospheric turbulence in terms of background atmospheric parameters inferred using MST radar at Gadanki (13.5°N, 79.2°E)

Indian mesosphere-stratosphere-troposphere (MST) radar is located at Gadanki (13.5 degrees N, 79.2 degrees E) in a tropical zone of India. In this region the background atmospheric parameters such as atmospheric winds, temperature, and humidity show a distinct change from monsoon to winter season. For example, the monsoon season is dominated by tropical easterly jet winds in the upper troposphere (i.e., 14-17 km), and the winter season is dominated by westerly winds with peak value at about 12-14 km. The basic wind patterns in the two seasons differ significantly, and this is expected to give rise to differences in the characteristics of atmospheric turbulence parameters in the two seasons. In this paper, various atmospheric turbulence parameters such as eddy dissipation rate (epsilon), eddy diffusivity (K(h)), and horizontal scale length (l(0) and L(B)) are obtained for the first time for the monsoon and winter seasons by using the available data sets from MST radar. An attempt is made to understand and explain the seasonal variability of these turbulence parameters in terms of the observed changes in the background atmospheric conditions.