Mapping the tidal flats of Kuwait Bay using Sentinel-2 data and GEE

Abstract

Tidal flats, unique coastal wetlands, offer vital ecological services such as pollutant removal, carbon storage, and shoreline stability. Kuwait Bay hosts the Arabian Gulf’s largest tidal flat ecosystem, which is crucial for biodiversity. Despite their importance, these tidal flats face threats from nature and human activities, leading to a widespread decline in their spatial extent. This study aims to map Kuwait Bay’s tidal flats with Sentinel-2 data and the Google Earth Engine (GEE) platform. Spectral index analysis revealed that the mNDWI is the most suitable index for representing the maximal water extent, whereas the NDVI is appropriate for determining the minimal water extent. The performance of each index is validated through confusion matrices, with overall accuracies ranging between 96 and 87% and F1 scores ranging between 0.87 and 0.93. The combination of the GEE platform with index analysis, image processing, and accuracy assessment techniques offers a precise mapping method at local and national scales in arid areas. The results revealed that Kuwait Bay’s tidal flats cover 157.2 km², with 60% along the northern coast of Kuwait Bay and 40% in Sulibikhat Bay and Doha Bay. This study represents the first attempt to map tidal flats in the Arabian Gulf region and will assist in developing monitoring and protection strategies, tracking tidal flat evolution, and achieving sustainable development goals related to coastal and marine environments.