Atmospheric Correction Of MODIS And Analysis Space-time Distribution Characteristics For Ocean Color In Bohai Sea

The main purpose of marine satellite remote sensing is to measure the distribution of chlorophyll concentration and suspended sediment concentration in the ocean, by which we can retrieve marine primary productivity, know its distribution well, figure out marine fishery, the circumstance of breeding resources and environmental quality, evaluates the soil erosion, keep port and channel safe. All of this will provide scientific evidence for the developing and utilizing of marine organism resources.There is no more than 20 percent marine radiation in the radiation capacity received by satellite sensors. So, atmospheric correction is a key link in chlorophyll retrieving course. Because the leaving water radiance retrieved is less than zero, the traditional atmospheric correction does not meet Chinese Ocean's needs. What's more The density of suspending substance in Chinese marine space is very high, which leads to the difficulty of chlorophyll extracting. So, traditional algorithm is not suitable for Chinese Ocean.In view of this, the article adopts the theory of spectrum of transportation and the atmospheric correction ways for SeaWIFS "clean water" case II water, takes the aerosol repeated scattering, which were neglected by Gordon's traditional atmospheric correction way, and ozone data(MOD07) and so on, into condition, improves and applies it into Bohai Sea's MODIS data for atmospheric correction, and gets the leaving-water radiance after rectifying of Bohai Sea. Comparing with the traditional one, this new way eliminates the areas whose leaving-water radiance is below zero. What's more, we calculate MODIS data of Bohai Sea according to the rectifying algorithms of OC3 counting way for MODIS chlorophyll retrieving by the First Institute of Oceanography, State Oceanic Administration, and get the retrieving image of Bohai Sea in four seasons. Analyzing these two on the basis of time and space, we can get the identical characteristics of chlorophyll distributing in Bohai Sea. As the same time the article takes Doctor Liao Yingdi's suspended sediment algorithms and analyzing the distribution in time and space, which shows that the distribution of suspended sediment concentration has an evident dependence on the position and seasons.Practice proves the improved atmospheric correction way correct and rational, andit supplies a new way for atmospheric correction of MODIS data. The distribution of chla concentration and suspended sediment concentration in time and space services for the development of our country's ocean color satellites and researcher of their new algorithms. Meanwhile, it provides technology support for the scientific management of coastal zone.