Homogeneous regions for rainfall distribution in the city of Rio de Janeiro associated with the risk of natural disasters

Understanding the occurrence of natural disasters in regions where the occurrence is high is very important, and it is known that the occurrence of disasters associated with intense rains is a source of research in different locations around the globe, being important not only for increasing accuracy of weather forecasting models, but important information for civil defense, where lives can be saved. The increase in the occurrence of natural disasters related to extreme rainfalls has become a problem of large urban centers, such as the city of Rio de Janeiro (CRJ). Thus, the identification of homogeneous regions for rainfall distribution (HRRD) becomes essential to identify regions at risks of floods and mass movements. The aim of this research was to identify HRRD in CRJ associated with the risk of natural disasters. The identification of homogeneous regions was carried out with the use of monthly rainfall data from 14 pluviometric stations spatially distributed in the study area between 1997 and 2018. Data derived from the MOD13A3 product were also used to identify the monthly temporal behavior of the vegetation areas in the CRJ during the period 2001 to 2020. Rainfall data were submitted to descriptive statistical analysis, and subsequently to Cluster Analysis. Cluster analysis identified 4 homogeneous groups regarding annual rainfall distribution. The nonparametric test analysis identified vegetation growth during the dry season and decay during the rainy season. These vegetation results found by the nonparametric Mann-Kendall test evidence the reduction in rainfall in the CRJ. The result showed relevance regarding physiographic aspects that characterize the rainfall dynamics in CRJ, highlighting areas favorable to the occurrence of natural disasters.