The Chl-a Concentration Retrieval Algorithm In East Sea And Its Application In The Ocean Primary Production Estimation

This study gives the introduction to the recent development of ocean color remote sensing, Chl-a concentration retrieval algorithms and the encountered difficulties in China seas. It emphasizes the method to revise the SeaWiFS atmosphere correction algorithm, Chl-a concentration retrieval algorithm, and the estimation of the primary production distribution in the East Sea.The SeaWiFS remote sensing reflectance data processed by SeaDAS are corrected by the remote sensing reflectance data obtained from Hyper-TSRB in East China Sea. We acquired a set of multi-band formulas to revise the atmosphere correction algorithms for the East Sea. Compared with the match-up data from Hyper-TSRB, the revised SeaWiFS remote sensing reflectance data are improved in the blue bands. Then a Chl-a concentration retrieval algorithm is developed for the East Sea by regressing the revised SeaWiFS remote sensing reflectance data and match-up in situ Chl-a concentration data. From the monthly averaged images of SeaWiFS data in 1998 processed by this algorithm and OC4ver4 algorithm, we find the Chl-a concentration in the coastal area such as the mouth of Yangzi River, Subei shoal are improved significantly according to the related papers and in-situ data. The data in 2003 are taken to validate this algorithm, and the average error is 30.86%, which is higher than the SeaWiFS OC4ver4 algorithm.Chl-a data retrieved by the new SeaWiFS data retrieval algorithm are put into two ocean primary production models (ASANUMA, Behrenfeld & Falkowski 1997) as an important parameter to estimate ocean primary production distribution in the East Sea.