Study on the circulation and water masses in the Northwest Pacific Ocean Using Argo profiling floats
1. Second Institute of Oceanography, SOA Hangzhou 310012.
2. key Lab of Ocean Dynamic Processes and Satellite Oceanography, SOA Hangzhou 310012
Abstract: The circulation and water masses in the area of northwest Pacific Ocean are studied using the drafting trajectory, temperature and salinity data obtained by Argo profiling floats. Results show that the main circulation in this area consists of the Subtropical Countercurrent (STCC), North Equatorial Current (NEC) /Equatorial Countercurrent (ECC), Kuroshio Current (KC), and the Mindanao Current (MC). It also indicates that STCC,NEC and ECC have the characteristics of deep water, which could be seen in the depth of 1500m. Near the offshore of Philippines, the NEC presents a complex current structure, of which may be related to the bifurcating of the current in this area. The T - S relation in this region indicates there exist 8 water masses: they are the North Pacific Tropical Surface Water (NPTSW), North Pacific Subsurface Water (NPSSW), North Pacific Subtropical Water (NPSTW), North Pacific Intermediate Water (NPIW), North Pacific Deep Water (NPDW) and Equatorial Surface Water (ESW), the South Pacific Subsurface Water (SPSSW) and South Pacific Intermediate Water (SPIW), respectively. There is no doubt that we can understand the variability of the Pacific warm pool and the formation mechanism of El Niño/La Niña better for the work.
Key words: Argo profiling float; Trajectory; T-S relation; Circulation; Water mass; Northwest Pacific Ocean