High-resolution Digital Terrain Model and Land-surface Parameters of São Sebastião and Ilhabela, southeastern Brazil

Rebeca Durço Coelho, Gabriella Labate Frugis, Camila Duelis Viana, Carlos Henrique Grohmann

Effective disaster risk management and detailed environmental studies in landslide-prone regions require high-resolution and accurate Digital Terrain Models (DTMs). This work describes the development of a 2~m-resolution lidar-based DTM and an extensive set of land-surface parameters (LSPs) for the municipalities of São Sebastião and Ilhabela, southeastern Brazil. The dataset was generated from approximately 650 GB of airborne lidar point clouds, processed through a reproducible workflow comprising ground point classification, merging of filtered files, Triangulated Irregular Network (TIN) interpolation, gap filling, and surface smoothing. The resulting high spatial resolution enabled the extraction of topographic parameters for local-scale landslide susceptibility analyses, surpassing the detail of existing photogrammetric and global DEMs for the region, revealing geomorphological features previously indiscernible, including past landslide deposits, drainage captures, and structural lineaments. The resulting products represent the first openly accessible high-resolution DTM for this region, made available via Zenodo, thus supporting applications in landslide susceptibility mapping, environmental modeling, and territorial planning. This open-access initiative contributes to bridging the gap in Brazil’s high-resolution topographic data availability and fosters both scientific research and evidence-based decision-making.