Dataset Supporting: Predicting Harmful Algal Bloom Risk in a Small Inland Reservoir Using Integrated Sentinel-2 and In Situ Data

This repository contains the processed dataset supporting the study, "Predicting Harmful Algal Bloom Risk in Barr Lake, Colorado Using Integrated Sentinel-2 and In Situ Data (2019–2025)." The dataset integrates in situ chlorophyll-a measurements, Sentinel-2-derived Normalized Difference Chlorophyll Index (NDCI) values, environmental variables, ecological zone classifications, and satellite–field matchup metadata collected from Barr Lake, Colorado, USA, between 2019 and 2025. Each observation represents a field sampling event matched to the closest valid Sentinel-2 Level-2A image acquisition within a ±5-day temporal window following quality-control procedures. The repository includes the processed dataset, a README file describing data collection and processing procedures, and a data dictionary containing variable definitions, units, and coding information. The dataset supports research on harmful algal bloom monitoring, satellite-assisted water-quality assessment, and probabilistic HAB-risk modeling in inland reservoirs.