Semi-automated Workflow for Mapping the Extent and Elevation Profile of Intertidal Zone of Parts of Gulf of Kutch, India, Using Landsat Time Series Data

Abstract

Mapping the topography of intertidal zones through in situ methods has many challenges associated with it and airborne techniques for determining the elevation profile are expensive. High temporal and spatial coverage provided by satellite remote sensing makes it highly efficient in assessing the extent and profile of intertidal zone even in remote and inaccessible areas. In this study, a semi-automated and scalable methodology is presented for generating the digital elevation model of the intertidal zone of Gulf of Kutch, India, thus bridging the existing gaps between terrestrial and marine elevation datasets. Time series multispectral data from the Landsat series are explored in the tidal height realm, and a median composting approach is used with NDWI and subsequent thresholding to effectively determine the extent of the intertidal zone. The median composite is used to handle the presence of noise or artefacts, thus ensuring the use of high-quality data and eradicating the problems associated with single-scene approaches previously used for such analysis. Using the capabilities of cloud-based computing platforms and openly accessible satellite data, this study aims to map the extent and 3D distribution of intertidal flats in a hostile coastal environment.