The Impact Of Climate Change On Inter-annual And Long Term Variation Of The Salinity Of Bohai Sea

The special geographic environment of Bohai Sea makes the variation of its salinity complicated by shallow-sea and land-induced impact. Meanwhile, it emphasizes Bohai Sea's significant role in the development of our nation's marine economy. The variation of salinity could influnce the near-shore circulation and ecologic environment, thus it has theoretical importance in fishery, marine construction and the durable exploitation and developing. With global climate changing, the salinity of Bohai Sea could inevitably be infected. For exmple, during the El-Nino event in the year of 1982~1983,the northern part of China suffered from severe drought and sharply decreased precipitaion, and the salinity of Bohai Sea increased incredibly.Early research was highly interested in such event, as well as the inter-annual and long term trend of the salinity of Bohai. Besides effects of the runoff from land and water exchange with North-Yellow Sea, the salinity is , in local meteorology sense, related to precipitation-evaporation domained freshwater flux, summer moonsoon and pressure. At the same time, in global perspective, the salinity variation has similar periods to El-Nino and Southern Oscilation(ENSO), as well as Pacific Decaldal Oscilation (PDO), which similarity could probably be expained by ENSO or PDO using local freshwater flux as medium.Therefore this paper will concentrate on this topic, and work on the potential ways by which the changing climate places its influnce on salinity, via looking into two crucial relationship: salinity with local meteorology and local meteorology with climate. Deploying GEFA in this work, the independent non-local feedback of 6 climate-variable of the Sea Surface Temperature(SST) of tropical Pacific, North Pacific and Indian Ocean are assessed. The results show: 1) The changing of climate adjusts monsoon system and vapor transport, which have effect on local meteorology of Bohai Sea, like precipitation, evaporation, monsoon, pressure,etc.. 2) The Indian Ocean Basin Mode(IBOM) is the key mode for the precipitation variation, which increases when IBOM is positve. Secondly is the Quasi-Bienniel Mode of El-Nino, which has a negtive effect. 3) Victotia Mode is the key mode for evaporation, while the northwest Pacific Ocean is the most significant area; the secondary mode is IOBM. The warming of these oceans enhences the evaporation over Bohai Sea. 4) Therefore Indian Ocean probably plays the most important part in the salinity variation of Bohai Sea.Tropical Pacific acts mainly through affecting IOBM. The northwest Pacific is also important.