Patterns of extreme precipitation in Santos

Abstract

Analysis of extreme precipitation events in different time scales over Santos is presented using the rain gauge network for the period 1980-2015. Located in the humid tropics, the area presents high annual total rainfall, particularly concentrated in spring and summer. However, the rainiest month-January-was also the one with the most homogeneous distribution. More than 40% of the days presented precipitation, which ranged from 0.1 to 332.9 mm. The precipitation variability was quite high, a fact observed in all scales evaluated, which reveals that the mechanisms that generate precipitation in the area are distinct throughout the year. The high precipitation variability is particularly important in the case of daily distribution: for instance, 25% of the rainy days responded for 71% of the total rainfall. Such concentration is a key element in the outbreak of numerous hazards, such as floods and landslides, that cause extensive property damage and loss of life, being the worst situations registered when extreme precipitation episodes coincide with storm surges.