东海赤潮多发区非均匀叶绿素浓度剖面对遥感反射比的影响

Effects of A Non-Uniform Profile of Chlorophyll Concentration on Remote Sensing Reflectance in the East Sea Where Red Tides Occur Frequently

赤潮增殖过程中,藻类首先在次表层发育,并形成非均匀的叶绿素浓度剖面,一般呈高斯分布。利用Hydroli-ght4.1模拟180组数据用于研究该过程对遥感反射比的影响。东海为赤潮多发区,通过比较叶绿素浓度在垂直非均匀和垂直均匀情况下的模拟结果,给出高斯分布模型4个参数对遥感反射比的影响。可得到以下初步结论:叶绿素浓度非均匀剖面参数的变化主要影响遥感反射比的绿黄波段,且有向长波段移动的趋势,而对蓝、红波段几乎没有影响;垂直非均匀情况下的遥感反射比要高于垂直均匀的情况。

A non-uniform profile of chlorophyll concentration will form during the developing period of the evolution of red tides as the algae grows in the sub-surface, which can be described with Gaussian function. 180 groups of numerical simulations of radiative transfer are used to study its effects on remote sensing reflectance with Hydrolight 4. 1. The simulations of a non-uniform profile of chlorophyll concentration are compared with homogeneous one. Effects of four parameters of Gaussian function on Rrs are discussed respectively. It can be concluded that the values of remote sensing reflectance on green-yellow bands is higher with a non-uniform profile, a trend of peak shift in green-yellow bands is also shown in the results. Few effects on blue and red bands is found respectively.