Development of a mass movement susceptibility map using the information value method and open data for the cities of Caraguatatuba, São Sebastião and Ubatuba

• Grant number: 23/12662-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2023
• End date: November 30, 2024
• Field of knowledge: Engineering - Civil Engineering - Geotechnical Engineering
• Principal Investigator: Anna Silvia Palcheco Peixoto
• Grantee: Graziele Fernandes Garcia
• Host Institution: Faculdade de Engenharia (FE). Universidade Estadual Paulista (UNESP). Campus de Bauru. Bauru , SP, Brazil

Abstract

At the end of 2018, the Intergovernmental Panel on Climate Change published the impact of the temperature increase of around 1.5°C over the next 30 years, compared to the time of the Industrial Revolution. In 2021, a correction in the methodology led to more pessimistic predictions, potentially reaching an increase of 4.5°C. In this context, Southeast Brazil is one of the regions indicated to experience an increase in precipitation, while the Northern region, in contrast, will suffer from drought. The region encompassing São Sebastião, Caraguatatuba, and Ubatuba, in the northern coast of the state of São Paulo, was heavily affected during the summer of 2022/2023 due to high volumes of rain, landslides, and floods. With this in mind, the primary objective of this research is to contribute to the development of susceptibility maps that can subsequently be dynamically applied to constantly changing realities, providing insights for planning the construction of more resilient communities. First, historical data of geotechnical and hydrological disaster occurrences in the state of São Paulo between 2000 and 2020 will be quantified and spatially analyzed based on the natural disaster database of IPMet - Center for Meteorology of Bauru - FC/Unesp. The factors to be considered (geology, geomorphology, slope, slope aspect, and land use) will be collected from available web sources (open data). Geology and geomorphology will take into account available shapefiles, as well as Geological Maps (Scale 1:500,000) and Geomorphological Maps (Scale 1:1,000,000) of the State of São Paulo. Slope and slope aspect will be derived from the digital elevation model, DEM, and QGIS (open-source software) add-ons. Detailed land use and occupation data will consider the census sector, occurrence dates, and intervals of census collections for the years 2000, 2010, and 2022. Weighting will utilize the informative value technique, allowing not only the assessment of the quantification of a specific type of disaster in a particular characteristic but also the coverage area of the same and the performance of the factors considered in the model. The susceptibility map will categorize 5 classes ranging from very low to very high. Lastly, given Brazil's vast dimensions and diversity, the advantage of developing this methodology lies in its potential for replication in other locations. It relies solely on open data and employs local data for weighting factors, making it adaptable to changes caused by various actions occurring in the region.