We addressed the mesoscale structure variation of the central South China Sea （SCS） with the measurements by a long-lived Argo float and a high-resolution ATLAS buoy during 1998-2002. T-S diagram indicates cooling a...We addressed the mesoscale structure variation of the central South China Sea （SCS） with the measurements by a long-lived Argo float and a high-resolution ATLAS buoy during 1998-2002. T-S diagram indicates cooling and freshening events in 2000 and 2001 with lower salinity （0.5-0.8） and lower temperature （1-1.7℃）. Significant decrease in the net heat flux and increase in the precipitation suggest that the cooling and freshening is due to extra forcing by the atmosphere. Additional to large year-to-year changes, intraseasonal variability is moderate in the research area. The axis of the maximum intraseasonal temperature and salinity signals are mainly located on the thermocline, Typically, amplitude and period of intraseasonal temperature is about 2℃ and 40-60 days, and that of salinity is 0.34）.5 and 35-60 days. Rapidly-changing winds, heat flux, and precipitation are critical in controlling the intraseasonal fluctuations of the mixed layer of the area. Studies on heat and freshwater balance in the mixed-layer further suggest that horizontal advection plays an important role in intraseasonal fluctuation in the upper ocean. In addition, the energetic mesoscale propagation radiated from the east boundary is linked to the intraseasonal variability in winter.展开更多
基金Supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (Nos.KZCX1-YW-12-01,KZCX2-YW-BR-04)the Knowledge Innovation Program of the Chinese Academy of Sciences (Nos.SQ200916,SQ200809)+1 种基金the National Natural Science Foundation of China (No.40806003)the National High Technology Research and Development Program of China (863 Program) (No.2008AA09A402)
文摘We addressed the mesoscale structure variation of the central South China Sea （SCS） with the measurements by a long-lived Argo float and a high-resolution ATLAS buoy during 1998-2002. T-S diagram indicates cooling and freshening events in 2000 and 2001 with lower salinity （0.5-0.8） and lower temperature （1-1.7℃）. Significant decrease in the net heat flux and increase in the precipitation suggest that the cooling and freshening is due to extra forcing by the atmosphere. Additional to large year-to-year changes, intraseasonal variability is moderate in the research area. The axis of the maximum intraseasonal temperature and salinity signals are mainly located on the thermocline, Typically, amplitude and period of intraseasonal temperature is about 2℃ and 40-60 days, and that of salinity is 0.34）.5 and 35-60 days. Rapidly-changing winds, heat flux, and precipitation are critical in controlling the intraseasonal fluctuations of the mixed layer of the area. Studies on heat and freshwater balance in the mixed-layer further suggest that horizontal advection plays an important role in intraseasonal fluctuation in the upper ocean. In addition, the energetic mesoscale propagation radiated from the east boundary is linked to the intraseasonal variability in winter.
