Impactos socioeconômicos e ambientais dos desastres associados às chuvas na cidade do Recife-PE.

Abstract

This study had the objective of determining and classifying the threshold values of rainfall as well as for evaluating the social, economical and environmental impacts of the disasters associated to the rains in the city of Recife-PE. The methodology followed six distinct steps: classification of thresholds for determining the daily, monthly and annual rainfall intensity; evaluation of the social, economical and environmental impacts of the disasters associated to rainfall intensity; mapping of disasters risk and vulnerability in the Recife communities; elaboration and application of 300 questionnaire to evaluate the population vulnerability; use of the RCLIMDEX (version 1.9.0) to calculate possible climatic trends; and elaboration of a rainfall Alert System for the city of Recife-PE. In the daily rainfall analyses it was observed that when there are occurrences of precipitation in the categories of very strong and strong rains, also occurs slips and few flooding points. The moderate intensity rains also may cause slips mainly points of flooding. There was not occurrence of damage associated to weak rains, however, when accumulated rainfall greater than 30 mm occurs in consecutive days before an event of weak rain may occur slipping. The occurrence of consecutive days with rains before an event of very strong, strong and moderate rain contributes to the occurrence of disasters. Despite the extreme events of intense rains been observed mainly between the months of March and July these events may occur in the other months of the year. It was a frequent occurrence of slipping and flooding due to rains associated to the lack of infrastructure like the population social and economical conditions. The partnership and commitment of society, civil defense and other public agencies makes the tripod witch when acting together make stronger and dynamic the actions really effective for mitigating or solving the problems due to disasters. Most of the Recife`s neighborhoods show very strong and strong risks to disasters, mainly in the South and West regions with the higher index of risks. The population socioeconomic vulnerability with lies in the poorer areas was considerate high while the environmental vulnerability was very high. Local changes in rainfall and air temperature were diagnosed for the 47 years analyzed with an increase of occurrence of extreme events from the 80`s, with daily rainfall greater than 100 mm in few days. It was also observed an increase in maximum and minimum air temperatures resulting in an increase in the heat waves in the region. The disasters due to rains and possible climatic trends require the deployment of an alert system which is relevant to reduce or even control the population vulnerability and the risks to disasters.