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Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Microphysical and thermodynamical features of two tropical systems, namely Hurricane Ivan and Typhoon Conson, and one sub-tropical, Catarina, have been analyzed based on space-born radar PR measurements available on the TRMM satellite. The procedure to classify the reflectivity profiles followed the Heymsfield et al (2000) and Steiner et al (1995) methodologies. The water and ice content have been calculated using a relationship obtained with data of the surface SPOL radar and PR in Rondonia State in Brazil. The diabatic heating rate due to latent heat release has been estimated using the methodology developed by Tao et al (1990). A more detailed analysis has been performed for Hurricane Catarina, the first of its kind in South Atlantic. High water content mean value has been found in Conson and Ivan at low levels and close to their centers. Results indicate that hurricane Catarina was shallower than the other two systems, with less water and the water was concentrated closer to its center. The mean ice content in Catarina was about 0.05 g kg-1 while in Conson it was 0.06 g kg-1 and in Ivan 0.08 g kg-1. Conson and Ivan had water content up to 0.3 g kg-1 above the 0ºC layer, while Catarina had less than 0.15 g kg-1. The latent heat released by Catarina showed to be very similar to the other two systems, except in the regions closer to the center.No presente trabalho foram analisados as características microfísicas e termodinâmicas de dois sistemas tropicais, o Furacão Ivan e o Tufão Conson, e um sub-tropical, Catarina, a partir de medições feitas com o radar PR a bordo do satélite TRMM. Na análise, os perfis de refletividade foram classificados conforme as técnicas de Heymsfield et al (2000) e Steiner et al (1995) e em seguida foram calculados os conteúdos de água e gelo, a partir de uma relação obtida no Estado de Rondônia (Brasil). Com estes perfis calculou-se a taxa de aquecimento diabático devido a liberação de calor latente conforme Tao et al (1990). Após serem comparados os três furacões, fez-se uma análise mais detalhada do Catarina, que foi o primeiro furacão oficialmente registrado no Atlântico Sul. Os resultados mostraram que o Ivan e o Conson tiveram um alto teor médio de água, especialmente nos níveis mais baixos e perto de seus centros. Os resultados indicaram que o furacão Catarina foi mais raso, tinha menor teor de água líquida e mais concentrada próximo do centro. O teor médio de gelo no Catarina foi cerca de 0,05 g kg-1, enquanto no Conson foi de 0,06 g kg-1 e no Ivan 0,08 g kg-1. O Conson e o Ivan tiveram teor de água de até 0,3 g kg-1 acima da isolinha de 0ºC, enquanto que o Catarina teve menos de 0,15 g kg-1. A taxa de aquecimento, devido à liberação de calor latente, no Catarina, mostrou ter magnitudes similares aos outros dois sistemas, com maiores diferenças nas regiões próximas do núcleo.