| Always in the past, aerosol's uncertainty in some aspects, such as its components composition and its optical properties, etc, is the major factor which affects the accuracy level of ocean color remote sensing atmospheric correction over the Huanghai Sea and the East China Sea. At the same time, the validity problem of the satellite remote sensing aerosol product is causing widespread concern among the correlating researchers at home and abroad. On the one hand, the effect of the atmospheric correction process in NASA's standard MODIS ocean color product remains to be checked over Eastern China Seas; on the other hand, satellite remote sensing aerosol optical depth needs wide evaluation urgently in this sea area. Because the high quality in-situ measured data over Chinese eastern coastal region is deficient, the two aforementioned jobs are few carried out.MODIS standard ocean color product (normalized water-leaving radiance product) include 869 nm aerosol optical depth dataset which is a by-product retrieved in its atmospheric correction process. As a kind of quality control and evaluation indicator, this aerosol optical depth data can represent the accuracy level of MODIS ocean color remote sensing atmospheric correction, in the meantime, it can also be used in the marine aerosol monitoring and study as a kind of aerosol satellite-retrieved product. The accuracy evaluation of this kind of aerosol optical depth data at Eastern China Sea is significant for advantage of the ocean optical remote sensing atmospheric correction algorithm as well as improving the precision of satellite-retrieved marine aerosol optical depth. In this paper, the in-situ data of sky radiometer observed on ship at Eastern China Seas during five cruises from April 2006 to November 2007 are used to validate the corresponding 869 nm aerosol optical depth data included in MODIS standard ocean color products. The spatial box of 10 km×10 km and temporal interval of±1 hour are used as the matching criterion. The results show that:72% of match-up data fall close to, or within the expected error range ofΔτ=±0.03±0.05τ. There are some differences in the precision of MODIS-derived aerosol optical depth according to seasons and regions. The data consistency over the East China Sea is better than the Huanghai Sea, while the data consistency in the winter of 2006 is better than the fall of 2007. In the fall of 2007, MODIS retrieval values are systematically overestimated. The reason for this phenomenon was analyzed. It seems that twelve pre-calculated aerosol models used by MODIS retrieval algorithms can't match the optical properties of the actual seasonal aerosol very well, and further analysis with all of match-up data confirmed the conclusion. Based on the further analysis, it is concluded that due to existence of the absorbing aerosol in the East Asian area, the overvaluation of single scattering albedo in the pre-calculated aerosol models'look-up tables is a common phenomenon. At some of stations, extinction coefficients in aerosol model look-up tables agree well with in-situ measurement, but multiple-scattering versus single-scattering relationship expression K maybe have a great error.
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