DATASET - Adaptation and implementation of the HOTSED framework for assessing seasonal scenarios and short-term weather extremes in a high-altitude watershed of the Eastern Alps

In this study, we presented the first adaptation and implementation of the HOTSED framework in a high-altitude watershed of the Eastern Italian Alps chosen as pilot area. HOTSED was applied to assess the spatio-temporal variability of sediment source hotspots driven by rainfall-induced surface runoff across different climatic conditions and rainfall intensities. We analyzed four seasonal scenarios and four daily scenarios, including an ordinary event and three extreme events with different return periods (10-year, 30-year, and 50-year). A pre-existing polygon-based geomorphological map was used to spatially define sediment sources across the study area. The geomorphic Potential of each Sediment Source (PSS) was estimated through a qualitative scoring of map attributes, supported by semi-quantitative, spatially distributed indices, including slope, permafrost distribution, and a proxy for frost-cracking incidence on the bedrock. Structural Sediment Connectivity (STC) was estimated using a geomorphometric index based on a Digital Terrain Model. For each scenario, a proxy for the Potential for Sediment Transport (PST) was computed using a rainfall-calibrated index, applying a 0°C ground surface temperature threshold to exclude snow-covered areas. All components were then integrated through a raster-based equation, yielding the HOTSED model. In this dataset, for each analysed scenario, we provide the main raster input data used (i.e., PSS, STC, PST, and the snowfall coefficient δ), as well as the final model outputs.
The dataset contains 16 folders: 8 scenarios (i.e., 4 seasonal scenarios + 4 short-term daily scenarios) with 2 different configurations (i.e., catchment outlet and main channels). Each folder contains 5 raster files in GEOTIFF format. A brief description of each raster file is provided in the Supplemental Information of this datasets metadata.