A bio-optical dataset collected during the 1998?C2007 period in the Yellow and East China Seas (YECS) was used to provide alternative empirical ocean-color algorithms in the retrieval of chlorophyll-
a (Chl-
a), total suspended matter (TSM), and colored dissolved organic matter (CDOM) absorption coefficients at 440 nm (ag
440). Assuming that remote-sensing reflectance (Rrs) could be retrieved accurately, empirical algorithms for T
Chl (regionally tuned Tassan??s Chl-
a algorithm) in case-1 waters (T
Chl2i in case-2 waters), T
TSM (regionally tuned Tassan??s TSM algorithm), and T
ag440 or C
ag440 (regionally tuned Tassan??s or Carder??s ag
440 algorithm) were able to retrieve Chl-
a, TSM, and ag
440 with uncertainties as high as 35, 46, and 35%, respectively. Applying the standard SeaWiFS Rrs, T
Chl was not viable in the eastern part of the YECS, which was associated with an inaccurate SeaWiFS Rrs retrieval because of improper atmospheric correction. T
Chl behaved better than other algorithms in the turbid case-2 waters, although overestimation was still observed. To retrieve more reliable Chl-
a estimates with standard SeaWiFS Rrs in turbid water (a proxy for case-2 waters), we modified T
Chl for data with SeaWiFS normalized water-leaving radiance at 555 nm (nLw
555) > 2 mW cm
?2 ??m
?1 sr
?1 (T
Chl2s). Finally, with standard SeaWiFS Rrs, we recommend switching algorithms from T
Chl2s (for case-2 waters) to MOC
Chl (SeaWiFS-modified NASA OC4v4 standard algorithm for case-1 waters) for retrieving Chl-
a, which resulted in uncertainties as high as 49%. To retrieve TSM and ag
440 using SeaWiFS Rrs, we recommend empirical algorithms for T
TSM (pre-SeaWiFS-modified form) and MT
ag440 or MC
ag440 (SeaWiFS Rrs-modified forms of T
ag440 or C
ag440). These could retrieve with uncertainties as high as 82 and 52%, respectively.
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