Persistence and Comprehensiveness of Extreme Precipitation Events in the South of Brazil: Space Variability and Atmospheric Patterns

Abstract

The southern region of Brazil is characterized, due to its geographical location, by the diversity of meteorological systems operating throughout the year, resulting in adverse weather conditions. This work analyzes the extreme events of precipitation, characterizing them according to their persistence and comprehensiveness, and the related atmospheric patterns. The development of a computational algorithm allowed the identification and knowledge of the spatial comprehensiveness of the extreme precipitation events, which were classified in a comprehensive and noncomprehensive character, resulting in four precipitation groups identified according to the criteria of intensity, persistence and comprehensiveness. The results showed that summer is the preferred season for the occurrence of extreme events in all the analyzed categories, a greater number of events occur between the northern Rio Grande do Sul and Paraná, and for the cases of Persistent Rain, the Santa Catarina coast is a region favorable to this type of event. Among the main atmospheric processes for the occurrence of extreme events with a comprehensive character are the humidity availability in the lower layers of the troposphere, along with jet in high level and a dug in medium levels.

Keywords:
rainfall; atmospheric patterns