DETECTION OF WATER OBJECTS USING NDWI WITH GOOGLE EARTH ENGINE (CASE STUDY OF THE KHOREZM REGION)
Keywords:
NDWI, remote sensing, Google Earth Engine, water monitoring, Sentinel-2, spectral index, Khorezm.Abstract
In this study, the spatial and temporal changes of water bodies in the Khorezm region were analyzed based on remote sensing data. The study was conducted on the Google Earth Engine platform, and the NDWI (Normalized Difference Water Index) was calculated using Landsat 5 and Sentinel-2 satellite images from 2010, 2018, and 2025. The obtained results showed a significant variability of the water bodies. In particular, between 2010 and 2018, the water area decreased from 214.53 km² to 140.16 km², it partially recovered to 164.17 km² in 2018–2025. Overall, a decreasing trend in water surface area was observed during the 2010–2025 period. Spatial analysis showed that water bodies are primarily associated with the Amu Darya and irrigation canals. The study's findings confirm the significant impact of climate change and anthropogenic factors on water resources. The application of the NDWI index has proven to be an effective and rapid method for identifying water bodies. This approach is of great importance for monitoring and sustainable management of water resources in arid regions.
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