An Algorithm for Estimating Suspended Sediment Concentrations in the Coastal Waters of India using Remotely Sensed Reflectance and its Application to Coastal Environments

Document Type: Original Research Paper

Authors

1 Centre for Earth & Space Sciences, University of Hyderabad, Hyderabad, India – 500 046

2 National Remote Sensing Centre, Hyderabad, India– 500037

3 Centre for Earth & Space Sciences, University of Hyderabad, Hyderabad, India – 500 046 Centre for Spatial Information Science, Dept. of Natural Environment Studies, University of Tokyo, Japan

4 Central Institute of Fisheries Technology, Cochin, India

Abstract

This study presents an empirical relationship of suspended sediment concentrations (SSCs) in
the coastal waters, which is derived from the conventional methods, to radiometer remote sensing reflectance values (Rrs) and satellite data in coastal waters of Kerala. An algorithm is then developed to utilize both in situ SSCs measured from conventional methods and Rrs values. This algorithm is validated with the SSCs retrieved from Oceansat-2 Ocean Colour Monitor (OCM) data. A significant coefficient of determination (R2=0.62) is observed between the SSCs measured in situ and satellite derived SSCs. Reflectance values from more than two spectral wavelength bands are also employed to test the accuracy of results. Satellite derived SSCs range from 1- 40 mg/L in the coastal waters off Cochin, southwest India. The regional algorithm developed for the study area gives better results than Tassan’s algorithm, and this algorithm can be used in estimation of SSC for coastal waters of western India.

Keywords