Desastres naturais no Estado do Ceará: uma análise de episódios pluviométricos extremos

Abstract

The aim of this study is to establish criteria for the definition of both normal and extreme values for the rain in the state of Ceará and check their relationship with the occurrence of natural disasters. Statistical methodologies (the quantile technique and the maximum precipitation methodology) were used in order to analyze extreme events in the State of Ceará in the time series in question (1980-2013). This methodology that is present in the Emergency Events Database (EM-DAT) also served as a subsidy to identify signs of disaster occurrence and their relationship with the occurrence of extreme events (droughts and floods) in different regions of the State of Ceará. The results obtained after applications of statistical techniques allowed counting and identifying various heavy rainfall events in many areas of the state, both in the coastal part and in most provincial municipalities. Most of these events were recorded in the early months of the year and were usually associated with activities of Intertropical Convergence Zone - ITCZ. The dry season phenomena were also identified from statistical techniques that made possible an analysis of the rain behavior in different regions of the state. The extreme events, based on their identification, showed some evidence of impact (number of people affected, emergency decrees, etc.) that provided the outbreak of a natural disaster. The provincials municipalities, located in occurrence areas of depressão sertaneja were the most affected by drought. However, floods are not only restricted to coastal or mountainous parts of the state and end up impacting also in municipalities located in the Sertão. It is humanly impossible to prevent the occurrence of extreme events in the state. However, the society and the government must adopt measures that significantly minimize the impacts, thus enabling a coexistence culture with the natural disasters.