Overview This repository contains high-resolution (1 km) spatial datasets for global fallout radionuclides across the Southern Hemisphere (extending to 20°N). The data includes spatial predictions, uncertainty estimates, and model applicability assessments for Cesium-137 ($^{137}Cs$) and Plutonium-239+240 ($^{239+240}Pu$) inventories in soil. Associated Publication These datasets support the research presented in the following study: "Radioactive fallout legacy of nuclear tests in soils of the Southern Hemisphere" Submitted to: Science Advances Technical Specifications Spatial Resolution: 1 km (30 arc-seconds) Coordinate Reference System (CRS): [WGS 84] Units: [Bq/m²] and [% for CV] Data Content For both $^{137}Cs$ and $^{239+240}Pu$, the repository provides: Prediction Maps (.tif): Spatial distribution of radionuclide inventories. Uncertainty & CV Maps (.tif): Standard deviation and Coefficient of Variation for reliability assessment. Area of Applicability (.shp): Vector masks identifying the reliable model domain (Gridcode 1 = Applicable). To cite the database, please use: Avcıoğlu, A., Dicen, G., Gupta, S., Alewell, C., Evrard, O., Sabatier, P., Angot, H., Vandromme, R., Cerdan, O., & Meusburger, K. (2026). Radioactive fallout legacy of nuclear tests in soils of the Southern Hemisphere. Science Advances. (Submitted). Documentation Please refer to the README.txt (or README.md) file included in this repository for detailed metadata, file structures, and usage instructions.