Abstract
Variations of temperature and salinity in the upper ocean are observed by the R/V Hakuho-Maru, when she stayed at the fixed station at the equator, 156°E, for 15 days in November 1992. The weather was calm for most of the period, and the temperature of the surface mixed layer increased slightly. Analyses suggest that heat fluxes through the sea surface and meridional advection explain most of the change of the heat storage in the mixed layer. EOF and isopycnal analyses suggest wave motion and intrusion of off-equatorial water are the main processes for the variation of temperature and salinity in the upper ocean, along with fluxes through the sea surface and mixing process in the mixed layer.
