Long-term variations of temperature and salinity of the Bohai Sea and their influence on its ecosystem

Long-term variations of the sea surface salinity (SSS), air temperature (AT) and sea surface temperature (SST) of the Bohai Sea during 1960-1997 were analyzed. They all showed positive trends. The trends of the annual mean SSS, AT and SST of the Bohai Sea were, respectively, 0.074 y(-1), 0.024 degreesC y(-1) and 0.011 degreesC y(-1). The increases of AT and SST were consistent with, the recent warming in northern China, in the Huanghai Sea (Yellow Sea) and in the East China Sea. The rise of SSS can be attributed to the rapid reduction of the total river discharge into the Bohai Sea, as well as to the increase inflow of high salinity water from the Huanghai Sea. It may also be attributed to increasing human use of river water and increases in evaporation from the sea surface. These changes in the marine environment seemed to have important influence on the Bohai Sea ecosystem. (C) 2001 Elsevier Science Ltd. All rights reserved.