An extensive data set of Lagrangian measurements of sea surface temperature, sea surface salinity and mixed layer circulation will used in conjunction with Eulerian measurements from other sources (moorings from the Tropical Ocean Global Atmosphere (TOGA) program's observing system and moorings deployed during the Coupled Ocean Atmosphere Response Experiment (COARE)) to assemble a space-time description of the surface circulation and sea level of the western tropical Pacific Ocean over a 40-month period. The goal is to determine the horizontal structure and evolution of the advective properties of oceanic dynamic fields in the tropical mixed layer on time scales of days to months. In addition, the hypothesis that large spatial scale variations of heat and salinity at the equator are determined by advection from wind-driven Yoshida jets will be examined. The upper ocean data set will also be used to parameterize the near surface turbulent flux convergence as a function of surface fluxes, provide an alternate way to determine surface fluxes.