Based on the EOF analyses of Absolute Dynamic Topography satellite data, it is found that, in summer, the northern South China Sea （SCS） is dominated by an anticyclonic gyre whilst by a cyclonic one in winter. A con...Based on the EOF analyses of Absolute Dynamic Topography satellite data, it is found that, in summer, the northern South China Sea （SCS） is dominated by an anticyclonic gyre whilst by a cyclonic one in winter. A connected single-layer and two-layer model is employed here to investigate the dynamic mechanism of the circulation in the northern SCS. Numerical experi- ments show that the nonlinear term, the pressure torque and the planetary vorticity adveetion play important roles in the circulation of the northern SCS, whilst the contribution by seasonal wind stress curl is local and limited. Only a small part of the Kuroshio water intrudes into the SCS, it then induces a positive vorticity band extending southwestward from the west of the Luzon Strait （LS） and a negative vorticity band along the 200 m isobath of the northern basin. The positive vorticity field induced by the local summer wind stress curl is weaker than that induced in winter in the northern SCS. Besides the Kuroshio intrusion and monsoon, the water trans- ports via the Sunda Shelf and the Sibutu Passage are also important to the circulation in the northern SCS, and the induced vorticity field in summer is almost contrary to that in winter. The strength variations of these three key factors （Kuroshio, monsoon and the water transports via the Sunda Shelf and the Sibutu Passage） determine the seasonal variations of the vorticity and eddy fields in the northern SCS. As for the water exchange via the LS, the Kuroshio intrusion brings about a net inflow into the SCS, and the monsoon has a less effect, whilst the water transports via the Sunda Shelf and the Sibutu Passage are the most important influencing factors, thus, the water exchange of the SCS with the Pacific via the LS changes dramatically from an outflow of the SCS in summer to an inflow into the SCS in winter.展开更多
Based on the 18-year （1993-2010） National Centers for Environmental Prediction optimum interpolation sea surface temperature （SST） and simple ocean data assimilation datasets, this study investigated the patterns ...Based on the 18-year （1993-2010） National Centers for Environmental Prediction optimum interpolation sea surface temperature （SST） and simple ocean data assimilation datasets, this study investigated the patterns of the SST anomalies （SSTAs） that occurred in the South China Sea （SCS） during the mature phase of the E1 Nifio/Southem Oscillation. The most dominant characteristic was that of the out- of-phase variation between southwestern and northeastern parts of the SCS, which was influenced primarily by the net surface heat flux and by horizontal thermal advection. The negative SSTA in the northeastern SCS was caused mainly by the loss of heat to the atmosphere and because of the cold-water advection from the western Pacific through the Luzon Strait during E1 Nifio episodes. Conversely, it was found that the anomalous large-scale atmospheric circulation and weakened western boundary current during E1 Nifio episodes led to the development of the positive SSTA in the southwestern SCS.展开更多
In the past 10 years （2004-2013）, annual open cruise during late summer provided new opportunities for comprehensive studies in the Northern South China Sea （NSCS）. The 10-year field investigation program was carr...In the past 10 years （2004-2013）, annual open cruise during late summer provided new opportunities for comprehensive studies in the Northern South China Sea （NSCS）. The 10-year field investigation program was carried out by the South China Sea Institute of Oceanology, Chinese Academy of Sciences （SCSIO, CAS）. Measurements inclu- ded water mass property, ocean circulation, atmospheric structure, and chemical and biological elements. The observation data collected during these open cruises have been intensively used in the studies of marine oceanographic, meteorological, chemical, and biological processes in the NSCS. In this study, comprehensive assessment of data application in oceanographic and meteorological studies is provided： （1） the property and variability of water masses in different layers; （2） the distribution of main currents and three-dimensional structure of mesoscale eddies; and （3） atmospheric structure and its feedback to the ocean. With the continuance of open cruises, it is feasible to construct high- quality, gridded climatological marine meteorological datasets in the NSCS in the near future.展开更多
基金supported by theNational Natural Foundation of China (NSFC) Grants Nos. 41025019,40976009 and 41206009
文摘Based on the EOF analyses of Absolute Dynamic Topography satellite data, it is found that, in summer, the northern South China Sea （SCS） is dominated by an anticyclonic gyre whilst by a cyclonic one in winter. A connected single-layer and two-layer model is employed here to investigate the dynamic mechanism of the circulation in the northern SCS. Numerical experi- ments show that the nonlinear term, the pressure torque and the planetary vorticity adveetion play important roles in the circulation of the northern SCS, whilst the contribution by seasonal wind stress curl is local and limited. Only a small part of the Kuroshio water intrudes into the SCS, it then induces a positive vorticity band extending southwestward from the west of the Luzon Strait （LS） and a negative vorticity band along the 200 m isobath of the northern basin. The positive vorticity field induced by the local summer wind stress curl is weaker than that induced in winter in the northern SCS. Besides the Kuroshio intrusion and monsoon, the water trans- ports via the Sunda Shelf and the Sibutu Passage are also important to the circulation in the northern SCS, and the induced vorticity field in summer is almost contrary to that in winter. The strength variations of these three key factors （Kuroshio, monsoon and the water transports via the Sunda Shelf and the Sibutu Passage） determine the seasonal variations of the vorticity and eddy fields in the northern SCS. As for the water exchange via the LS, the Kuroshio intrusion brings about a net inflow into the SCS, and the monsoon has a less effect, whilst the water transports via the Sunda Shelf and the Sibutu Passage are the most important influencing factors, thus, the water exchange of the SCS with the Pacific via the LS changes dramatically from an outflow of the SCS in summer to an inflow into the SCS in winter.
基金Supported by the National Natural Science Foundation of China(No.41306026)the Scientific Research Foundation of the Third Institute of Oceanography,SOA(No.2013009)+1 种基金the National Basic Research Program of China(973 Program)(No.2011CB403504)the National Special Research Fund for Non-Profit Marine Sector(No.201005005-2)
文摘Based on the 18-year （1993-2010） National Centers for Environmental Prediction optimum interpolation sea surface temperature （SST） and simple ocean data assimilation datasets, this study investigated the patterns of the SST anomalies （SSTAs） that occurred in the South China Sea （SCS） during the mature phase of the E1 Nifio/Southem Oscillation. The most dominant characteristic was that of the out- of-phase variation between southwestern and northeastern parts of the SCS, which was influenced primarily by the net surface heat flux and by horizontal thermal advection. The negative SSTA in the northeastern SCS was caused mainly by the loss of heat to the atmosphere and because of the cold-water advection from the western Pacific through the Luzon Strait during E1 Nifio episodes. Conversely, it was found that the anomalous large-scale atmospheric circulation and weakened western boundary current during E1 Nifio episodes led to the development of the positive SSTA in the southwestern SCS.
基金Constructive comments by three reviewers are gratefully acknowledged. Special gratitude goes to our colleagues Drs. Rui Shi, Jian Li, and Ke Huang for their help in data collection. This work was supported by the National Basic Research Program of China （2011CB403501）, the Strategic Priority Research Program of the Chinese Academy of Sciences （XDAll010403 and XDA11010 302）, Sanya and Chinese Academy of Sciences Cooperation Project （2013YD77）, the National Natural Science Foundation of China （41276024, 41206011, 41106028, 41406038, 41306012, 41306014, 41476014, 41476012 and 41406131）, the Infrastructure Facilities Project of Xisha station and Nansha station （KZCX2-EW-Y040）, and the Major National Scientific Instrument and Equipment Develop- ment Project （2012YQ12003910）.
文摘In the past 10 years （2004-2013）, annual open cruise during late summer provided new opportunities for comprehensive studies in the Northern South China Sea （NSCS）. The 10-year field investigation program was carried out by the South China Sea Institute of Oceanology, Chinese Academy of Sciences （SCSIO, CAS）. Measurements inclu- ded water mass property, ocean circulation, atmospheric structure, and chemical and biological elements. The observation data collected during these open cruises have been intensively used in the studies of marine oceanographic, meteorological, chemical, and biological processes in the NSCS. In this study, comprehensive assessment of data application in oceanographic and meteorological studies is provided： （1） the property and variability of water masses in different layers; （2） the distribution of main currents and three-dimensional structure of mesoscale eddies; and （3） atmospheric structure and its feedback to the ocean. With the continuance of open cruises, it is feasible to construct high- quality, gridded climatological marine meteorological datasets in the NSCS in the near future.
