Authors: Haibin Su*, Texas A&M University Kingsville
Topics: Remote Sensing, Coastal and Marine, Water Resources and Hydrology
Keywords: Landsat 8, Sentinel-2, bathymetry, mapping
Session Type: Paper
Presentation File: No File Uploaded
Bathymetric information is crucial to the study and management of coastal zones. Passive remote sensing provides a cost-effective alternative to acoustic surveys and bathymetric LiDAR techniques. Most existing studies estimated water depth from multispectral imagery in shallow coastal and inland waters by establishing the relationship between image pixel spectral values and known water depth measurements, in which the loglinear inversion model is most widely used. The application of this model on high spatial resolution imagery such as IKONOS, QuickBird and the family of WorldView satellites can offer an accurate and detailed monitoring. However, these observations are limited by their areal coverage and relatively high cost. In contrast, freely available Landsat imagery can be utilized to yield reliable and updated bathymetric information, especially since the launch of Landsat-8 in 2013. Compared to Landsat 5 and 7, Landsat 8 introduces the new coastal/aerosol band. In this study, we compared the accuracy of water depth estimates from Landsat 7, Landsat 8 and Sentinel-2 imagery with different combinations of spectral bands to see if the coastal/aerosol band can help improve the accuracy of water depth estimates. A case study of southeastern shore of Kauai Island, Hawaii has been conducted. The results demonstrate that Landsat 8 imagery provides much improved accuracy compared to Landsat 7 due to its improved radiometric resolution. However, the water depth estimate accuracy from Landsat 8 was barely improved when coastal/aerosol band is utilized along with blue and green bands, probably due to the high correlation between coastal and blue bands.