Global evidence indicates that ongoing climate change is already impacting, and will continue to impact in the future, urban populations and, furthermore, precarious urban occupations, especially in middle- and low-income countries in the global south, are likely to suffer the consequences of these impacts in a more direct and devastating way. In this way, this article, by analyzing the direct impacts of a recent extreme event in an extremely socially and spatially segregated Brazilian urban area, is of great scientific significance, especially as it demonstrates the disproportionality of the impacts on formal and informal urban areas.

As for the methods used and the general quality of the input data in the analytical model, the work follows the necessary rigor and presents the results clearly. As a caveat, the work would benefit from a better development of the concept of susceptibility. Vulnerability is developed in a substantial way, however, taking into account the idea that risk can be understood as the interface between susceptibility and vulnerability, characterizing the natural susceptibility of the São Sebastião region, especially due to its very steep topography, would be beneficial from a conceptual point of view. In addition, it would be interesting to deal in a little more detail with some of the other layers of complexity of the specific event on which the article is based: there was also a failure in the risk communication process, as the local government had received official warnings of a large amount of rain forecast some time in advance (https://agenciabrasil.ebc.com.br/geral/noticia/2023-02/centro-de-monitoramento-emitiu-alertas-tres-dias-antes-dos-temporais) but chose not to take any action. In addition, the risk areas were previously mapped, according to a report by the São Paulo State Institute for Technological Research (https://www.sidec.sp.gov.br/map_risco/uploads/doc1637073821.pdf).

Overall, the paper is presented clearly with appropriate language, figures, and references, and its conclusions have great potential for applying better tools to public policies for monitoring and assessing risks related to extreme events in cities in the global south. 

Please see the attached document for comments and suggestions.