Application of Sentinel-2 Level 1C Satellite Imagery for Inland Surface Water Bodies Detection in Temperate Climates Based on Water Indices

This study evaluates the effectiveness of selected spectral indices – Normalized Difference Water Index (NDWI), Modified Normalized Difference Water Index (MNDWI) and Sentinel Water Mask (SWM) – for detecting surface water using Sentinel-2 Level 1C satellite imagery in temperate climate conditions. Analyses were conducted for two study areas in the middle Vistula River basin, including the main river channel, tributaries and small water bodies. The temporal scope (2019–2022) allowed assessment of the applicability of the indices to environmental change monitoring. All three indices demonstrated high accuracy in detecting large water bodies, but their performance varied when identifying smaller water features. NDWI exhibited the highest qualitative and quantitative performance, with the best overall accuracy and kappa coefficient, and showed the greatest scene-to-scene consistency. SWM produced moderate results, while MNDWI performed the least effectively. The findings confirm that the index performance depends on both algorithm characteristics and environmental or imagery parameters. Therefore, testing multiple indices is recommended to select the most suitable one for specific study areas and research objectives.