Alguns aspectos dinâmicos e termodinâmicos de um vórtice ciclônico de altos níveis (VCAN) sobre sua região de atuação.

Abstract

The objective of this work is to analyze from the of Dynamics and thermodynamics viewpoint one of the various Cyclonic Vortex of Upper Air (CVUA) that were observed over the Northeast Brazil (NEB) and Amazonia during January, 2002. NCEP´s reanalyzes data (u and v wind components, geopotential height, specific humidity, omega motion and temperature) plus satellite data were used to infer some characteristic properties of the CVUA. All the fields refer to 00, 06, 12 and 18 UTC and cover the 12 standard isobaric levels (1000, 925, 850, 700, 600, 500, 400, 300, 250, 200, 150 e 100hPa), together with their daily averages. Satellite imagery in the visible as well as infrared and water vapor channels were used to validate the results of the analyzes; in particular TRMM satellite that furnished the precipitation data along the edge of the CVUA. The analyses of the upper air streamlines fields show that the genesis of CVUA was due to the presence of an InterHemispheric Bifurcation over the western coast of Africa (AIB) and a pair of anticyclones, namely the Bolivian High (BH) and the Angolan High. During its life cycle, the studied CVUA show a quite remarkable behavior with a varying translation speed and its persistent zonal trajectory probably because the existing vortical systems in its neighborhood. The technique of using relatively unemployed variables such as the thermodynamic functions q dot , apparent heating and moisture sources ( q1 and q2) were very useful tools as well as the vertical sections of the secondary circulation that showed a clear link between upper and lower level systems, mainly regarding the convective activity in the peripheral of the CVUA. As part of the results, it is mentioned the potentiality of the used tools to infer the depth, width and intensity of this large scale vertical system, the processes of energy conversion implied in the secondary circulation and its associated precipitation pattern.