A Kinetic Energy Analysis of the Meso β-Scale Severe Storm Environment

Abstract

An area of intense thunderstorms occurred within the special rawinsonde network collecting data on 20?21 May 1979, the fifth day of the Atmospheric Variability Experiment-Severe Environmental Storms and Mesoscale Experiment (AVE-SESAME). The data are at the meso ?-scale, i.e., 75 km spacing and 3 or 1.5 h intervals. They are used to perform a kinetic energy analysis of the near storm environment. The mesoscale storm environment is characterized by cross-contour generation of kinetic energy, transfers of energy to nonresolvable scales of motion (negative dissipation), horizontal flux divergence and upward transport of energy. These processes are maximized within the upper troposphere and are greatest during times of strongest convection. Current mesoscale values are much larger than previous results based on synoptic-scale data. Energy budgets are obtained at 3 h intervals from the routine National Weather Service rawinsonde network. A comparison of results from the same analysis region, but derived from the two different resolutions, reveals several common features. Complex vertical variations in winds (energy) over southeastern Oklahoma are also examined in detail. Motions not detected by the meso ?-scale input data appera to play an important role in the energy balance of some layers. A sensitivity analysis is presented to quantify uncertainties in the energy budget terms.