Google Earth Engine Tutorial 8: Water Quality Analysis Using Remote Sensing Techniques (Turbidity)

Water Turbidity Estimation and Mapping Using Sentinel-2 Imagery in Google Earth Engine In this video, you will learn how to estimate water turbidity using Sentinel 2 Images in the Google Earth engine. Turbidity is the level of suspended sediments in water, indicating water clarity or how clear the water is. The Normalized Difference Turbidity Index (NDTI) is an index used to estimate the turbidity of water bodies, which is a measure of water quality related to the number of suspended particles (like sediments, plankton, or pollutants) in the water. Turbidity can affect aquatic ecosystems and the overall health of a water body, so monitoring it is important for environmental management. The NDTI is derived using remote sensing data, especially from satellite imagery such as that from the Sentinel-2 satellite. It leverages the reflectance values from specific bands of the satellite, particularly the green (B3) and red (B4) bands, to assess turbidity. The formula for the NDTI is: NDTI= B3-B4/B3+B4 Where: B3 (Green band): Sensitive to water chlorophyll and suspended sediments. B4 (Red band): Sensitive to the presence of turbidity, which is caused by particles in the water. Interpretation Positive NDTI values: Indicate higher turbidity. Negative NDTI values: Indicate lower turbidity. The NDTI values typically range from -1 to 1, and higher positive values correspond to more turbid (less clear) water. Code link: https://code.earthengine.google.com/8...