Spatial Analysis of Affected Areas by Extreme Hydrological Events in Rio de Janeiro (The Host City for the 2016 Olympic Games)—Brazil

摘要

The most frequent types of disasters in Brazil are associated with extreme hydrological events. Adding to this situation, in Brazil, there are the extreme sociospatial discrepancies that are historically constructed. They leave marks in space, making specific areas, for political interest or not, more vulnerable to the different mentioned processes. To this extent, the public management should plan actions and, also, it may act in a more holistic way adding new trends, such as, the use of geotechnologies that are applied to environmental management in the realm of urban planning. From a case study in the city of Rio de Janeiro, this paper aims to contribute and draw attention to such issues. It may reach its target through pointing and spatially analyzing which areas are in the most critical situation related to the occurrence of extreme hydrological events. To achieve this goal, it was proposed a methodology to inventory the occurrence of inundation/flooding for a certain period, in this case 2001-2008. Besides, the methodology could systematize data and integrate them with other important issues for supporting the process of identification and analysis of the most critical areas. Historical aspects of occupation and the most vulnerable socio-environmental aspects were raised, too, in order to validate the highlighted areas. This integration was enabled concerning the support of geoprocessing techniques. The results of this integration subsidized the mapping and spatial analysis of the affected areas in the city and the criticality in relation to the extreme hydrological events. Finally, it was possible to observe that the identification of the most critical affected areas does not mean the exhaustion of the subject. The location of these areas is directly linked to the sample that was used as the basis for analyses. This data set only represents recorded events by the Municipal Civil Defense respecting the studied time frame. However, the results permit to take notes and raise relevant environmental questions about the roots and the occurred impacts that were originated from the extreme hydrological events, which have been observed in recent decades.