CHLOROPHYLL A IN TURBID PRODUCTIVE WATERS: TESTING THE LIMITS OF NIR-Red ALGORITHMS

A conceptual model was developed for the estimation of chlorophyll a (Chl) in turbid productive waters, based on the optical information in the red and in the near-infra-red (NIR) spectral regions. The calibration of the model with spectral bands of satellite-carried sensors MERIS and MODIS, proved applicable over two orders of magnitude of Chl concentration. The goal of the current work was to test the model in an environment with a limited range of Chl variation, where Chl concentration ranged from 4.6 to 20.8 mg m. The model calibrated in US Nebraska lakes was able to predict Chl concentration with RMSE of less than 1.5 mg m. Our work thus indicates the potential of the model to be usefully applied to Chl estimation in inland and coastal waters without further need of parameterization and calibration.