This project focuses on measuring the magnitude and variability of the South China Sea (SCS) and Indonesian Seas transport/exchange (SITE) of the water mass and heat flux in the Karimata Strait for two years using moorings. These data will be used as baseline for calibration and validation of a high-resolution, nested Regional Ocean Model System (ROMS). The proposed research is an international collaboration of three nations: the United States, Indonesia, and China. The main goal is to combine both the in situ and numerical model to quantify a contribution of SITE flow on the total Indonesian Throughflow transport, thus enhancing our understanding of the variability and predictability of regional and global ocean circulation and climate. Although Indonesian Throughflow measurements have been conducted for more than two decades, the SITE flow has received little observational attention, under the assumption that it didn?t play an important role. New evidence from observations and numerical modeling indicates that the SITE flow is important on seasonal and inter-annual time scales, and in reshaping the vertical structure of the main Indonesian Throughflow pathway through the Makassar Strait.
Intellectual Merit: The combination of in situ and numerical model in the proposed research will result in significant advances in understanding of (1) the variability of SITE flow and its associated heat-freshwater fluxes; (2) the effects of SITE flow on the primary Indonesian Throughflow and its consequence of the heat-budget to the Indian Ocean, global ocean thermohaline circulation and climate; (3) the roles of SITE flow in the SCS circulation, mesoscale dynamics, and heat transfer as well as its air-sea exchange; and (4) establishment of a basis for a long- term proxy monitoring system, as required to capture the low frequency Indonesian Throughflow variability.
Broader Impacts: The benefit to the broader oceanographic community will be to finally allow the Indonesian Throughflow to be faithfully simulated within ocean and climate models to enhance the monsoon, ENSO (El Nino-Southern Oscillation) , and climate prediction. In addition, the SITE project will promote international collaborations and will offer both research and education opportunities in the United States, Indonesia, and the People?s .Republic of China.