【摘要】 通过对2009年5月珠江口门内外水体光谱采样数据的分析处理,得到该海域水体离水光谱反射率及其负对数值;分别计算水体离水光谱反射率及其负对数与水体透明度的相关系数,发现后者与海水透明度的相关系数比前者要高出约11%。为便于应用卫星遥感数据开展南海海域水体透明度的反演,选用和Hyperion卫星数据相关波段中心波长相对应、且相关系数较高波长处的水体离水光谱反射率及其负对数为变量,分别建立线性、多项式、乘幂及指数的海水透明度拟合回归方程。经比较分析,发现采用559 nm处水体离水光谱反射率负对数的乘幂回归方程(拟合度R2=0.922 2,检验样本平均相对误差为18%)可获得较好的拟合结果,这为南海近岸海水透明度的卫星遥感反演提供了基础研究支撑。更多还原

【Abstract】 The water-leaving reflectance spectra of seawater were obtained through data collected at the Pearl River Estuary in May,2009.Their negative natural logarithmic values were also acquired by calculation.The correlation coefficients between secchi depths and water-leaving reflectance spectra of seawater and their negative natural logarithmic values were calculated.The correlation coefficients between secchi depths and negative natural logarithm values of water-leaving reflectance spectra of seawater are about 11% higher than the correlation coefficients between secchi depths and water-leaving reflectance spectra of seawater.According to the analytical result,the water-leaving reflectance spectra of seawater and their negative natural logarithm values whose correlation coefficients are maximum and whose locations are Hyperion satellite center wavelength were selected to formulate linear,polynomial,power and exponential regression equations which were used to fit seawater clarity.It is found that the power regression equation fitted by the negative natural logarithm values of water-leaving reflectance spectra of seawater at 559 nm can receive better results.The fitting degree R2 is 0.922 2 and the average relative error is 18% for the tested samples.The result obtained by the authors can provide support for retrieval of seawater clarity in South China Sea shore by satellite remote sensing.更多还原