Limiar de precipitação que pode gerar deslizamentos nos complexos de risco de Maceió

Abstract

Natural disasters are events that cause immeasurable losses, it is a theme that has been discussed worldwide. Atmospheric precipitation can cause disasters, gigantic proportions. In Brazil, in states such as Rio de Janeiro, sirens for the emission of alerts are triggered every year, informing the population about the possibility of occurrence of events of landslides, floods, floods, caused by heavy rains. In the state of Alagoas, some events were marked in the history of the state and the Country, as one of the big occurred, highlighting the year of 2010 where several municipalities were affected, and the year 2004, in Maceió, 14 people died, 1,090 were displaced, 450 were evicted. In the event of the year 2017, 7 people died in the city of Maceió, due to rainfall that fell in the rainy season. The municipality of Maceió is the most populous of the State of Alagoas and presents about 575 Risk areas, divided into 06 risk. The Civil Defense records the occurrences caused by several factors, among them the Strong rain. This work sought through the evaluations of the recorded occurrences of landslides and recorded rains, suggest rainfall thresholds for risks of Maceió, and pointed out that a general rule for the determination of thresholds should not apply because of the peculiar characteristics of each study region. The suggested thresholds were 40 mm for daily rains, with minimum values equal to or greater than 5 hours, and the accumulation of 100 mm during 2 rainy days.