Assessment of turbulent kinetic energy budget and boundary layer characteristics during pre-monsoon thunderstorm season over Ranchi

In the present work turbulent kinetic energy (TKE) budget and boundary layer characteristics are studied for an Indian tropical station Ranchi (23A degrees 25N, 85A degrees 26E), situated over Chota Nagpur plateau. The pre-monsoon months (March-May) data for years 2008-2010 has been used in the present study which is the period of severe thunderstorm over the North East India. TKE budget terms, dissipation rates, and normalized standard deviations of wind and temperature along with skewness of temperature have been analyzed to find out characteristic difference between days of thunderstorm and days of clear weather. Present study brought out significant variations in the turbulence transportation between the days of thunderstorm activity to that of fair weather days. Site and season specific relationships normalized standard deviations of wind and temperature with atmospheric stability during pre-monsoon thunderstorm and non thunderstorm days over Ranchi are proposed. One of the important outcomes of the study is proposing site specific relationships between TKE dissipation rates with respect to atmospheric stability. These results are useful in validating the mesoscale simulations of thunderstorm activity.