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海洋作为大气系统的一个下垫面，它的散射与吸收特性直接影响成像光谱仪接收的有关海洋特性信号的强弱，也是影响海洋—大气系统辐射传输精确计算的一个重要因子。反映海洋特性的一个重要量就是海洋总反射率，实验已证明海洋反射率较小，而且海洋反射的信号还要经过大气的散射和吸收才能到达接收体。那么，在各种大气条件下，大气上界接收的信号对总海洋反射系数的敏感度有多大，各种大气条件下大气的特征参数如气溶胶类型、光学厚度、相函数、太阳天顶角等对信号影响的大小，对我们认识大气性质及精确反演海洋特性有着重要意义。另外，在现有的目前普遍应用的Ｌｏｗｔｒａｎ－７大气辐射传输模式中，下垫面反照率为一给定的常数，是不随波长而变的Ｌａｍｂｅｒｔ反射体，而实际上海表反照率是波长的函数。因此，我们改进了Ｌｏｗｔｒａｎ－７中的下垫面模式，并以此模式和我们建立的海洋—大气耦合辐射传输模式分析了各参数对成像光谱仪接收信号敏感性
As an underlying surface of the atmospheric system, the scattering and absorption characteristics of the ocean directly affect the intensity of the signal of the ocean characteristic received by the imaging spectrometer, which is also an important factor that affects the accurate calculation of the radiation transmission in the ocean-atmosphere system. An important volume that reflects the characteristics of the oceans and seas is the total ocean reflectance. Experiments have shown that oceans reflect less and that signals reflected by the oceans have to be scattered and absorbed by the atmosphere to reach the receiver. Then, under various atmospheric conditions, how sensitive is the sensitivity of the signals received at the upper atmosphere to the total ocean reflectance? Atmospheric parameters such as aerosol type, optical thickness, phase function, solar zenith angle Such as the size of the signal impact on the understanding of the nature of the atmosphere and accurate inversion of marine characteristics is of great significance. In addition, in the existing Lowtran-7 atmospheric radiation transmission mode currently used, the underlying albedo is a given constant, which is a Lambert reflector that does not vary with wavelength, and the sea surface albedo actually has a wavelength of function. Therefore, we improved the underlying surface mode in Lowtran-7 and analyzed the sensitivity of each parameter to the imaging spectrometer received signal using this model and our established ocean-atmosphere coupled radiation transmission mode