Vorticity generation and energy budget over central Italy

Abstract

TEMP data for Milan, Brindisi, Cagliari and Rome from 1961 to 1965 have been processed to study vorticity generation and energy budget over central Italy. Cautious use of the kinematic method has provided satisfactory normal values of divergence. Vorticity generation at 500 mb and temperature changes in the lower half of the atmosphere are confirmed as being weak in the area considered. In January, divergence destroys cyclonic vorticity at 500 mb, and cooling by ascending motion compensates warm advection and diabatic heating in the lower half of the atmosphere, whereas descending motion and warm advection compensate diabatic cooling in the upper half of the atmosphere. Also in January, the dissipation of kinetic energy is found to be negative: there is an input of kinetic energy from smaller perturbations into the mean motion, probably in consequence of local baroclinic developments.