MODIS-derived ocean color products along the China east coastal region

Ocean water-leaving radiance spectra extending from the visible (blue) to the near-infrared (NIR) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) measurements are reported here for the China east coastal region. The China east coastal region contains some of the most consistently highly turbid coastal waters to be found anywhere. For turbid waters, standard MODIS data processing often produces significant errors in the derived ocean color products due to significant ocean water-leaving radiance contributions at the two NIR bands. In this paper, we demonstrate an atmospheric correction approach using MODIS short wave infrared (SWIR) bands for deriving more accurate ocean color products in coastal regions. The ocean is generally still black at the SWIR bands even for very turbid waters due to much stronger water absorption at the SWIR wavelengths. The approach has been tested for and applied to various coastal regions (e. g., the U. S. and China east coastal regions) using MODIS data. In situ data collected along the China east coastal region have been used to validate performance of the algorithm. Using MODIS Aqua measurements from July of 2002 to December of 2005, seasonal variations in the visible and the NIR ocean water-leaving radiances for the Hangzhou Bay in the China east coastal region are derived and analyzed. Very significant ocean NIR contributions along various locations in the China east coastal region (e. g., Hangzhou Bay) are observed.