Mapping characteristics of at-risk population to disasters in the context of Brazilian early warning system

Due to the increasing rise of climate-related disasters in the world, knowledge of risk, monitoring and early warning, dissemination and communication, and disaster preparedness have become demanded. Early Warning Systems (EWS) have been proposed as a strategy for reducing the vulnerability of populations living in at-risk areas. A current challenge in knowledge of risk and disaster preparedness is the inclusion of sociodemographic characteristics of the population in EWS. In order to contribute for an initial comprehension of the dimensions of vulnerability in Brazil, the aim of this paper is to understand the conditions of at-risk populations at an intra-urban scale and the potential application in the Brazilian EWS (BEWS). Through an integration of demographic data and landslide and flood risk mappings of 825 municipalities historically affected by disasters in Brazilian territory, an estimation of 8,266,566 people and 2,470,506 households was achieved. This result indicates that for every 100 inhabitants, 9 lived in disaster risk areas in Brazil. A novel database containing sociodemographic and infrastructure basic services data is available for specific analysis of those who are exposed to disasters. These data, associated with hazard forecast, are essential for effective early warnings, which allow actions focusing the reduction of human losses. The knowledge of at risk population in Brazil may contribute to the identification of the more critical areas that require priority response actions, such as the ones with more presence of elderly, children and a higher concentration of residents in households without sanitation, which are indicators of vulnerability.