Continental Scale Mapping of Tidal Flats across East Asia Using the Landsat Archive

Researchers have developed a novel method to map tidal flats over large continental scales, addressing a critical gap in understanding their global distribution and status. By leveraging the Landsat Archive, they mapped 86.8% of the coastline across China, North Korea, and South Korea with an accuracy exceeding 85%. The approach involves predicting tide heights at the time of image acquisition using a validated regional tide model, selecting images from the upper and lower 10% of the tidal range, and applying the Normalized Differenced Water Index (NDWI) to classify land and water. Subtracting high-tide from low-tide classified images delineates tidal flats, enabling large-scale coastal morphology mapping and monitoring. This method provides essential data for coastal adaptation to sea level rise, habitat loss monitoring, and ecosystem-based conservation efforts.

Murray, N., Phinn, S., Clemens, R., Roelfsema, C., & Fuller, R. (2012). Continental Scale Mapping of Tidal Flats across East Asia Using the Landsat Archive. Remote Sensing, 4(11), 3417–3426. https://doi.org/10.3390/rs4113417