Hydrographic field investigations in the Northern South China Sea by open cruises during 2004-2013

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 included 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.