An appraisal of surface chlorophyll estimation by satellite remote sensing in the South China Sea
Abstract:The OC4v4 algorithm, which is confirmed as a standard algorithm for the retrieval of ocean chlorophyll-a concentration (chl-a) from ocean colour satellite data, was appraised for its performance in the South China Sea (SCS). With in situ optical data and surface chl-a data collected on six cruises from 1997 to 2005 in the SCS, analysis showed a large discrepancy between the in situ and OC4v4-retrieved chl-a. The OC4v4 algorithm generally overestimates the chl-a in the investigated area; this possibly results from the relatively higher absorption of the chromophoric of dissolved organic matter (CDOM). To find a better algorithm, correlation analysis was carried out between the chl-a and the band ratio. Results showed that the remote sensing reflectance ratios, [image omitted] and [image omitted] , obtained the best correlation relationship. New algorithms were proposed based on the two band ratios. Compared with OC4v4, the new algorithms show better results and are suggested for the retrieval of chl-a from SeaWiFS or MODIS in the SCS.
Document Type: Research Article
Affiliations: 1: LED, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China,Graduate University of the Chinese Academy of Sciences, Beijing, China 2: LED, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
Publication date: November 1, 2008