Based on the comprehensive collection of the field observed salinity of the Bohai Sea (BHS) and the northern Huanghai Sea (NHS) from the 1950s to the present, the patterns of 10-years-averaged salinity at the diff...Based on the comprehensive collection of the field observed salinity of the Bohai Sea (BHS) and the northern Huanghai Sea (NHS) from the 1950s to the present, the patterns of 10-years-averaged salinity at the different layers in the recent five decades (the 1950s, the 1960s, the 1970s, the 1980s and the 1990s) are obtained by the spatial-temporal interpolation technique with the scrupulous data quality control in this study. Then, by combining the spatial-temporal interpolation technique with successive correction method, the annual distributions of salinity both in the BHS and in the NHS are obtained as well. The data analyses indicate that the overall salinity in the BHS and the NHS increases from the 1960s till the present, with the increase of annual mean salinity of 0.04 psu from the 1950s, and the maximum increase rate of salinity is about 0.14 psu/a in the Bohai Bay. The high salinity tongue extended significantly from the NHS into the BHS. The intensified eastern wind field is related to the western intrusion of the NHS warm current, which probably leads to the moving forward of the high salinity water mass into the BHS. However, it is rather different from the salinity distribution characteristics between the 1950s and the 1960s. The extensive precipitation in the 1960s could lead to an increase in the discharge of the Huanghe River, which might result in the decrease of salinity in the BHS. But the salinity isoline of 32 in the NHS still extended significantly into the BHS in the 1960s. Since the 1980s, the patterns of salinity distribution have changed thoroughly. The salinity in the central area of the BHS was low, while the salinity in the Bohai Bay and the Liaodong Bay was higher than the other regions with its horizontal salinity gradient decreasing in the 1980s. The Empirical Orthogonal Function Analysis (EOF) is also conducted to study the interannual salinity variability of the BHS and the NHS. The correlation coefficient between the time coefficient series of the main mode and the Huanghe River discharge can reach-64.57%. It can be concluded that salinity variation of the BHS and the NHS has strong negative correlation with the Huanghe River discharge.展开更多
基金The Hi-tech Research and Development Program(863 Program) of China under contract No2007AA09Z117comprehensive Survey and Assessment of China’s Coastal Sea Program(China ‘908’ Project) under contract No908-01-ST02China "973" Program under contract No 2005CB422302
文摘Based on the comprehensive collection of the field observed salinity of the Bohai Sea (BHS) and the northern Huanghai Sea (NHS) from the 1950s to the present, the patterns of 10-years-averaged salinity at the different layers in the recent five decades (the 1950s, the 1960s, the 1970s, the 1980s and the 1990s) are obtained by the spatial-temporal interpolation technique with the scrupulous data quality control in this study. Then, by combining the spatial-temporal interpolation technique with successive correction method, the annual distributions of salinity both in the BHS and in the NHS are obtained as well. The data analyses indicate that the overall salinity in the BHS and the NHS increases from the 1960s till the present, with the increase of annual mean salinity of 0.04 psu from the 1950s, and the maximum increase rate of salinity is about 0.14 psu/a in the Bohai Bay. The high salinity tongue extended significantly from the NHS into the BHS. The intensified eastern wind field is related to the western intrusion of the NHS warm current, which probably leads to the moving forward of the high salinity water mass into the BHS. However, it is rather different from the salinity distribution characteristics between the 1950s and the 1960s. The extensive precipitation in the 1960s could lead to an increase in the discharge of the Huanghe River, which might result in the decrease of salinity in the BHS. But the salinity isoline of 32 in the NHS still extended significantly into the BHS in the 1960s. Since the 1980s, the patterns of salinity distribution have changed thoroughly. The salinity in the central area of the BHS was low, while the salinity in the Bohai Bay and the Liaodong Bay was higher than the other regions with its horizontal salinity gradient decreasing in the 1980s. The Empirical Orthogonal Function Analysis (EOF) is also conducted to study the interannual salinity variability of the BHS and the NHS. The correlation coefficient between the time coefficient series of the main mode and the Huanghe River discharge can reach-64.57%. It can be concluded that salinity variation of the BHS and the NHS has strong negative correlation with the Huanghe River discharge.