Intra-seasonal to decadal variability and role of eddies in the low-latitude western boundary current off the Philippines

University Of Hawaii, Honolulu

Investigators

Abstract

The low-latitude western boundary current (LLWBC) of the Pacific has been shown to play an important role in the world?s climate. It plays a role in modulating the western Pacific warm pool and ventilating the equatorial thermocline, which are important for phenomena like El Nino/Southern Oscillation and Pacific Decadal Oscillation (PDO). This study combines all available observations with results from the OGCM for the Earth Simulator (OFES) and the Consortium for Estimating the Circulation and Climate of the Ocean (ECCO). The OFES has a higher (0.1deg) resolution and longer (1950-2003) period of integration, and its simulated LLWBC has proven to be one of the best available in a model. The ECCO has a relatively coarse (1deg×1/3deg) resolution and shorter (1982-present) period of integration, but its simulated passive and adjoint tracer provides a unique opportunity to trace the LLWBC. The project goals are to (1) complete the description of 3-dimensional structure and intraseasonal-decadal variability of the LLWBC, (2) examine the energy source of eddies and their impacts on the LLWBC, and (3) identify the origin, pathway, and fate of the LLWBC, with special reference to the intermediate depth off the Philippines. The results will contribute to assessing predictability of the Asia-Australia monsoon system, improving ENSO predictions, and understanding mechanisms of Pacific decadal variability, as well as various impacts of these phenomena. The project will support a postdoctoral researcher and will enhance infrastructure for research and education by establishing collaborations between different climate research groups in different institutions from different nations.