Roles of Divergent and Rotational Winds in the Kinetic Energy Balance Intense Convective Activity

Abstract

Contibutions of divergent and rotational wind components to the synoptic-scale kinetic energy balance are described using rawinsonde data at 3 and 6 h intervals from NASA’s fourth Atmospheric Variability Experiment (AVE 4). Two intense thunderstorm complexes occurred during the period. Energy budgets am described for the entire computational region and for limited volumes that enclosed storm-induced, upper-level wind maxima touted poleward of the convection. Although small in magnitude, the divergent wind component played an important role in the cross-contour generation and horizontal flux divergence of kinetic energy. The importance of VD appears directly related to the presence and intensity of convection. Although KD usually comprised lm than 10% of the total kinetic energy content generation of kinetic energy by VD was a major factor in the creation of upper-level wind maxima to the north of the storm complexes. Omission of the divergent wind apparently would lead to serious misrepresentations of the energy balance. A random error analysis is presented to assess confidence limits in the various energy parameters.