Analyses of marine environment characteristics of the deep-sea observation sites innorthern South China Sea
TAN Junfeng
SONG Xiaoyang
ZHANG Fei
YANG Jie
CHANG Yongguo
Abstract：The CTD and ADCP mounted on the submarine dynamic platform were used to conduct long-term and fixed-point observation of the deep waters in the northern South China Sea.Based on data such as thermohaline and ocean currents,we analyzed the marine environment characteristics by various data processing methods.According to the data analyzed,the temperature and salinity of the deep wa-ters in the northern South China Sea were relatively stable with some seasonal differences,and the main characteristics were low temperature,high salt and high density.The current velocity ranged from-100 mm/s to 100 mm/s,and mainly about 50mm/s.The current velocity was inversely proportional to water depth,forming a typical deep ocean velocity profile.Tidal current harmonic analysis demon-strated that tidal currents are dominated by diurnal and semidiurnal tides,and the flow ellipse rotated with depth and changed in a complex way.Different vertical modes were calculated based on the Empir-ical Orthogonal Function(EOF)analysis of the eastern and northern components of the tidal currents,with a variance contribution for the first two modes of at least 85％,higher order modes were less than 5％.The results revealed a strong barotropic character for the tidal currents of this region.
Keywords：Northern South China Seaenvironment characteristicCTDADCPocean currenttidal current
Publication Date：2023-12-28
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：7( 109-115 )