【作者】 吴璟瑜； 商少凌； 洪华生； 曾银东；

【Author】 WU Jing yu, SHANG Shao ling, HONG Hua sheng, ZENG Yin dong ( Key Laboratory of Marine Environmental Science, Ministry of Education, Xiamen University, Xiamen 361005, China)

【机构】 厦门大学海洋环境科学教育部重点实验室；

【摘要】 利用珠江口2002年11月颗粒物质(包括浮游植物与非色素颗粒)及有色溶解有机物质(CDOM)吸收系数的测量,尝试修正MODIS半分析算法经验方程。原算法中建立的浮游植物吸收系数aφ(λ)与aφ(675)之间的双曲线正切函数关系式可能并不符合珠江口这一高污染河口区的光学性质,故给出了aφ(λ)与aφ(443)的简单二次函数关系式。非色素颗粒吸收系数(ad)总体上远大于CDOM吸收系数(ag),所以,没有分离ad 和ag 而直接导出ag 并不切实可行;建议参数S取值0.012 nm-1。当然实用的珠江口MODIS半分析算法还需要进一步的调试与优化。更多还原

【Abstract】 In this paper, the absorption coefficients of particulates(including phytoplankton and nonpigmental particles) and colored dissolved organic matter(CDOM) measured in the Pearl River estuary area are used to make an amendment to the empirical equation of MODIS semianalytic algorithm. It is shown from the data analysis that the hyperbolic tangent function relation between phytoplankton absorption coefficient a φ(λ) and a φ(675) in the semianalytic algorithm is not likely to accord with the optical characters of seawater in the highly polluted Pearl River estuary area, so a simple quadratic function relation between a φ(λ) and a φ(443) is suggested. Generally speaking, the absorption coefficient of nonpigmental particles a d(λ) is much greater than the absorption coefficient of CDOM a g(λ), so it would be impracticable to directly derive a g(λ) without separating a d(λ) from a g(λ). In addition, it is suggested that the value of parameter S is taken as 0.012 nm -1 . Of course, further test and optimization are needed for deriving a practical MODIS semianalytic algorithm in the Pearl River estuary area.更多还原