Conductivity, temperature and depth(CTD) data collected along a zonal hydrographic section from the northern margin of the Amery Ice Shelf on 25-27 February 2008 by the 24th Chinese National Antarctic Research Exped...Conductivity, temperature and depth(CTD) data collected along a zonal hydrographic section from the northern margin of the Amery Ice Shelf on 25-27 February 2008 by the 24th Chinese National Antarctic Research Expedition (CHINARE) cruise in the 2007/2008 austral summer are analyzed to study thermohaline structures. Analysis reveals warm subsurface water in a limited area around the east end of the northern margin, where the temperature, salinity and density have east-west gradients in the surface layer of the hydrographic section. The localization of the warm subsurface water and the causes of the CTD gradients in the 'surface layer are discussed. In addition, the results from these CTD data analyses are compared with those from the 22nd CHINARE cruise in the 2005/2006 austral summer. This comparison revealed that the thermoclines and haloclines had deepened and their strengths weakened in the 2007/2008 austral summer. The difference between the two data sets and the cause for it can be reasonably explained and attributed to the change in ocean-ice-atmosphere interactions at the northern margin of the Amery Ice Shell展开更多
Three warm currents, the Kuroshio, its shelf intrusion branch in the northeast of Taiwan and the Taiwan Warm Current (hereafter TWC), dominate the circulation pattern in the East China Sea (hereafter ECS). Their o...Three warm currents, the Kuroshio, its shelf intrusion branch in the northeast of Taiwan and the Taiwan Warm Current (hereafter TWC), dominate the circulation pattern in the East China Sea (hereafter ECS). Their origination, routes and variation in winter and summer are studied. Their relationship with four major high and low temperature centers is analyzed. Differing from the previous opinion, we suggest that the four major centers are generated to a great extent by the interaction of the currents in the ECS. In summer, a cold water belt in the northeast of Taiwan is preserved from winter between the Kuroshio and the TWC. The shelf intrusion branch of the Kuroshio separates the water belt, and two low temperature centers generate in the northeast of Taiwan. In the southern ECS, the TWC transports more heat flux northward to form a warm pool. But it is separated in the lower layer by the cold water driven by the intrusion branch of the Kuroshio. So the TWC and the intrusion branch of the Kuroshio play a dominating role to generate the high temperature center. The interaction among the eastward TWC, the northward Tsushima Warm Current (hereafter TSWC) and the southward Su Bei Coastal Flow (hereafter SBCF) generates the low temperature center in the northern ECS. In winter, the strengthening of the shelf intrusion branch of the Kuroshio obscures the two low temperature centers in the northeast of Taiwan. For the weakening of the TWC, the high temperature center in the southern ECS vanishes, and the low temperature center in the northern ECS shifts to south.展开更多
基金supported by the National Basic Research Priorities Program of China (Grant no.2010CB950301)the National Natural Science Foundation of China (Grant no.40376009)+2 种基金the National Key Technology Research and Development Program of China during the 11th Five Year Plan (Grant no. 2006BAB08B02)the Program of Special Fund Basic ResearchOperating Expenses of First Institute of Oceanography,SOA (Grant no. FIO2010T01)
文摘Conductivity, temperature and depth(CTD) data collected along a zonal hydrographic section from the northern margin of the Amery Ice Shelf on 25-27 February 2008 by the 24th Chinese National Antarctic Research Expedition (CHINARE) cruise in the 2007/2008 austral summer are analyzed to study thermohaline structures. Analysis reveals warm subsurface water in a limited area around the east end of the northern margin, where the temperature, salinity and density have east-west gradients in the surface layer of the hydrographic section. The localization of the warm subsurface water and the causes of the CTD gradients in the 'surface layer are discussed. In addition, the results from these CTD data analyses are compared with those from the 22nd CHINARE cruise in the 2005/2006 austral summer. This comparison revealed that the thermoclines and haloclines had deepened and their strengths weakened in the 2007/2008 austral summer. The difference between the two data sets and the cause for it can be reasonably explained and attributed to the change in ocean-ice-atmosphere interactions at the northern margin of the Amery Ice Shell
基金supported by the key project of the National Natural Science Foundation of China under contract Nos 40730842 and 40706016the National Key Basic Research Program of China under contract No2006CB403605China"908" Project under contract No908-02-01-03
文摘Three warm currents, the Kuroshio, its shelf intrusion branch in the northeast of Taiwan and the Taiwan Warm Current (hereafter TWC), dominate the circulation pattern in the East China Sea (hereafter ECS). Their origination, routes and variation in winter and summer are studied. Their relationship with four major high and low temperature centers is analyzed. Differing from the previous opinion, we suggest that the four major centers are generated to a great extent by the interaction of the currents in the ECS. In summer, a cold water belt in the northeast of Taiwan is preserved from winter between the Kuroshio and the TWC. The shelf intrusion branch of the Kuroshio separates the water belt, and two low temperature centers generate in the northeast of Taiwan. In the southern ECS, the TWC transports more heat flux northward to form a warm pool. But it is separated in the lower layer by the cold water driven by the intrusion branch of the Kuroshio. So the TWC and the intrusion branch of the Kuroshio play a dominating role to generate the high temperature center. The interaction among the eastward TWC, the northward Tsushima Warm Current (hereafter TSWC) and the southward Su Bei Coastal Flow (hereafter SBCF) generates the low temperature center in the northern ECS. In winter, the strengthening of the shelf intrusion branch of the Kuroshio obscures the two low temperature centers in the northeast of Taiwan. For the weakening of the TWC, the high temperature center in the southern ECS vanishes, and the low temperature center in the northern ECS shifts to south.