Remote sensing research on the influence on the ocean color environment of the East and South China Sea from snowstorm in cold winter this year

At the beginning of 2008, the south area of China suffered a rare heavy snow and low temperature weather, which brought enormous economic lose and broke the environment. The abnormal weather also influenced the ocean color environment. Through analysis of MODIS remote sensing 3A data during 2 months before and after the snowstorm and low temperature weather, the author finds that, on the one hand,compared with same period of last year, the sea surface temperature (SST) from the East China Sea to the South China Sea (18°N-32°N 108°E-126°E descended 2.57°C; the average chlorophyll-a concentration(CHL-a)rose from 1.198 mg. m -3 to 1.75 mg. m -3 in the snowstorm and low temperature weather period from January 11 to 31 of 2008 which was 1.46 times more than that of the same period of last year. On the other hand, compared with the period before snowstorm,the SST decreased from 22.42°C to 18.34°C but the CHL-a rose from 1.32 mg. m -3 to 1.60 mg. m -3 after the snowstorm. In addition,the sea water transparency(SDD) had a certain increase in the open sea of South China Sea, but the suspended sediment concentration(SSC) increased significantly near the seashore, the Yangtse River Estuary and the Pearl River Estuary, which increased 200% compared with the period before the snowstorm 2008. Through researching and indicating, the main reason of increase of the CHL-a in the near seashore area(the I water) was more probably due to the increase of the SSC, and the CHL-a by remote sensing has greater error, which rising from the high SSC led to the increase of CHL-a; but in the open sea the increase of CHL-a is that the SDD improved and then the euphotic increased. As a result,this could promote the growth of primary productivity. Therefore, it faces the better applied foreground to monitor the influence on the ocean ecosystem environment caused by the snowstorm and low temperature weather through remote sensing.