The energy cycle in a cyclone over the Bay of Genoa

Abstract

Zonal available potential energy, eddy available potential energy, eddy kinetic energy and conversion of zonal to eddy potential energy have been evaluated for the period from 5 to 15 February 1986 using data from Wetterbericht charts. These terms were calculated for a limited domain ranging from 400N to 500N latitude and from 50E to 200E longitude. A cyclone developed over the Bay of Genoa during the considered period. The system formed simultaneously at all levels in the troposphere as was noticeable on the synoptic charts. The cyclone life cycle could be described by time variations of the eddy available potential energy, since it increased during the intensifying and decreased during the weakening stage of the system. A stability diagram has been used to examine connection of the cyclone amplification and calculated energy terms with conditions in the atmosphere presented by critical meridional temperature gradient. The results obtained by the stability diagram correspond to energy estimations. In those days for which the stability diagram indicated amplification of the cyclone, the eddy energy terms increased and so the cyclone growth was evident on the synoptic charts.