Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6362162 | Marine Pollution Bulletin | 2010 | 16 Pages |
Abstract
The retrieval of chlorophyll-a concentration from remote sensing reflectance (Rrs) data was tested with the NASA OC4v4 algorithm on the inner New Caledonian lagoon (Case 2) and adjacent open ocean (Case 1) waters. The input to OC4v4 was Rrs measured in situ or modeled from water's inherent optical properties (2001-2007). At open ocean stations, backscattering and absorption coefficients were correlated with chlorophyll (R2 = 0.31-0.51, respectively), in agreement with models for Case 1 waters. Taking spectrofluorometric measurement as reference, the OC4v4 model leads to an average underestimation of 33% of the chlorophyll concentration. For the lagoon waters, OC4v4 performed inadequately because the backscattering coefficient, highly correlated with turbidity and suspended matter (R2 = 0.98), was poorly correlated to chlorophyll (R2 = 0.42). The OC4v4 performance was better in deep lagoon waters for stations with a TDT index (Tchla Ã depth/turbidity) higher than 19 mg mâ2 NTUâ1 (R2 = 0.974, bias = 10.2%). Global Imager Rrs provided a good estimate of Tchla (R2 = 0.79, N = 28) in the deeper part of the lagoon.
Keywords
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Oceanography
Authors
Cécile Dupouy, Jacques Neveux, Sylvain Ouillon, Robert Frouin, Hiroshi Murakami, Sébastien Hochard, Guillaume Dirberg,