National Science Foundation grant awarded to Dr. R. Dwi Susanto to monitor Indonesian throughflow

The National Science Foundation (NSF) awarded Department of Atmospheric and Oceanic Science, Dr. R. Dwi Susanto a $0.75 million grant to monitor Indonesian throughflow (ITF), the only pathways of the Pacific to Indian Ocean exchange through the Indonesian seas, which is essential for understanding the role of the ocean in Earth’s climate system. The ITF plays an integral role in global ocean thermohaline circulation, directly impacting mass, heat and freshwater budgets of the Pacific and Indian Oceans and influences the El Niño Southern Oscillation (ENSO) and Asian-Australian monsoons. For example, ITF plays active role in redistributing the ocean warming, by transporting heat from the Pacific into the Indian Ocean and beyond. In the last 15 years, the Pacific Ocean warming is slow down (“hiatus”), while at the same time, Indian Ocean shows the highest increased in the upper layer ocean temperature.


To monitor the ITF, Dr. Susanto and team will deploy couple moorings (series of oceanographic instrument to measure the ocean current and water characteristics in Indonesian seas) for the next three years. Because field observations are logistically challenging and expensive, he will collaborate with scientists from the National Research and Innovation Agency (BRIN), Indonesia and the First Institute of Oceanography (FIO), China. This international collaborative program is called TRIUMPH (Throughflow Indonesian Seas, Upwelling, and Mixing Physics). It is multinational and multidiscipline.


Results will be available for the numerical modeling community, so will contribute to monsoon, ENSO (El Nino Southern Oscillation), climate predictions, as well as biogeochemistry and ecosystem models. Hence, results of the proposed work will benefit the broader oceanographic and climatological community. The project will support one graduate student, who will use the collected data for her/his PhD thesis.


A map of the pacific ocean

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Indonesian throughflow (ITF) pathways (Susanto et al., 2016). Purple and green circles and stars are the location of the oceanographic instruments deployed in the Indonesian seas. The ITF annual average from the Pacific to the Indian Ocean is 15 Sv (1 Sv = 1 million cubic meter/second).