Water characteristics of abyssal and hadal zones in the southern Yap Trench observed with the submersible Jiaolong  

作　　者：LIU Xuehai LIU Yongzhi CAO Wei SUN Chengjun 

机构地区：[1]First Institute of Oceanography,Ministry of Natural Resources,Qingdao 266061,China [2]Laboratory for Regional Oceanography and Numerical Modeling,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China [3]Key Laboratory of Marine Science and Numerical Modeling,Ministry of Natural Resources,Qingdao 266061,China

出　　处：《Journal of Oceanology and Limnology》2020年第3期593-605,共13页海洋湖沼学报（英文）

基　　金：Supported by the National Key Basic Research Program of China(973 Program)(No.2015CB755904);the National Natural Science Foundation of China(No.41276036)。

摘　　要：Using observations in an applied cruise of the submersible Jiaolong,water characteristics,geostrophic transport,and turbulent mixing in abyssal and hadal zones of the southern Yap Trench were studied.The spatial structures of deep water show that the abyssal water is cold,saline,and oxygen rich.The hadal water has very small changes in potential temperature and potential density,and a little decrease in salinity and obvious decrease in oxygen.The isotherm,isopycnal,and isohaline are depressed in abyss over the central trench.The turbulent mixing is enhanced in the near-bottom zone and the hadal water on the trench slope,especially at the steep slope,the dissipation rate and diffusivity is strong,which weakens the stratification.The geostrophic flows move southward in the western region of the trench and northward in the eastern region,indicating cyclonic circulation.In the central region of the trench,the water transport is^1.74 Sv southward.In the hadal zone,the northward and southward transports are balanced.Our analysis suggests that the abyssal water in the southern Yap Trench is from Lower Circumpolar Water(LCPW)and the hadal water seems to be of the isolated local water rather than LCPW.

关 键 词：Yap TRENCH ABYSSAL and hadal the SUBMERSIBLE Jiaolong diapycnal mixing geostrophic flows 

分 类 号：P714[天文地球—海洋科学]