scholarly journals Advection and diffusion of Indonesian Throughflow Water within the Indian Ocean South Equatorial Current

1997 ◽  
Vol 24 (21) ◽  
pp. 2573-2576 ◽  
Author(s):  
Arnold L. Gordon ◽  
Shubin Ma ◽  
Donald B. Olson ◽  
Peter Hacker ◽  
Amy Ffield ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Indonesian Throughflow ◽  
South Equatorial Current ◽  
The Indian Ocean ◽  
Equatorial Current ◽  
And Diffusion

scholarly journals A 20-Yr Average of the Indonesian Throughflow: Regional Currents and the Interbasin Exchange

2008 ◽  
Vol 38 (9) ◽  
pp. 1965-1978 ◽  
Author(s):  
Susan E. Wijffels ◽  
Gary Meyers ◽  
J. Stuart Godfrey
Keyword(s):  
Heat Fluxes ◽  
Ekman Transport ◽  
Indonesian Throughflow ◽  
South Equatorial Current ◽  
Near Surface ◽  
Surface Heat Fluxes ◽  
Interbasin Exchange ◽  
The Indian Ocean ◽  
Equatorial Current ◽  
Pass Through

Abstract Twenty years of monthly or more frequent repeat expendable bathythermograph data are used to estimate the mean geostrophic velocity and transport relative to 750 m of the Indonesian Throughflow (ITF) and its partitioning through the major outflow straits into the Indian Ocean. Ekman transports are estimated from satellite and atmospheric reanalysis wind climatologies. A subsurface maximum near 100 m characterizes the geostrophic ITF, but Ekman flows drive a warm near-surface component as well. A subsurface intensified fresh Makassar Jet feeds the Lombok Strait Throughflow (∼2 Sv; 1Sv ≡ 106 m3 s−1) and an eastward flow along the Nusa Tenggara island chain [the Nusa Tenggara Current (6 Sv)]. This flow feeds a relatively cold 3.0-Sv flow through the Ombai Strait and Savu Sea. About 4–5 Sv pass through Timor Passage, fed by both the Nusa Tenggara Current and likely warmer and saltier flow from the eastern Banda Sea. The Ombai and Timor Throughflow feature distinctly different shear profiles; Ombai has deep-reaching shear with a subsurface velocity maximum near 150 m and so is cold (∼15.5°–17.1°C), while Timor Passage has a surface intensified flow and is warm (∼21.6°–23°C). At the western end of Timor Passage the nascent South Equatorial Current is augmented by recirculation from a strong eastward shallow flow south of the passage. South of the western tip of Java are two mean eastward flows—the very shallow, warm, and fresh South Java Current and a cold salty South Java Undercurrent. These, along with the inflow of the Eastern Gyral Current, recirculate to augment the South Equatorial Current, and greatly increase its salinity compared to that at the outflow passages. The best estimate of the 20-yr-average geostrophic plus Ekman transport is 8.9 ± 1.7 Sv with a transport-weighted temperature of 21.2°C and transport-weighted salinity of 34.73 near 110°E. The warm temperatures of the flow can be reconciled with the much cooler estimates based on mooring data in Makassar Strait by accounting for an unmeasured barotropic and deep component, and local surface heat fluxes that warm the ITF by 2°–4°C during its passage through the region.

scholarly journals Oceanic Radiocarbon and Tritium On A Transect Between Australia and Bali (Eastern Indian Ocean)

Radiocarbon ◽  
2004 ◽  
Vol 46 (2) ◽  
pp. 567-581 ◽  
Author(s):  
Viviane Leboucher ◽  
Philippe Jean-Baptiste ◽  
Elise Fourré ◽  
Maurice Arnold ◽  
Michèle Fieux
Keyword(s):  
Indian Ocean ◽  
Continental Shelf ◽  
Equatorial Pacific ◽  
North Equatorial Current ◽  
Indonesian Throughflow ◽  
Data Set ◽  
Indonesian Archipelago ◽  
The Pacific ◽  
The Indian Ocean ◽  
Equatorial Current

Results are presented of radiocarbon and tritium measurements along a transect between the Australian continental shelf and the Indonesian coast of Bali. The stations lie in the easternmost part of the Indian Ocean, close to the sills over which the Indonesian throughflow (ITF) makes its way to the Indian Ocean. The present data, obtained as part of the Java-Australia Dynamics Experiment (JADE) in August 1989, complement the WOCE 14C and tritium data set on both sides of the Indonesian archipelago and give us the opportunity to discuss the origin of the water masses and timescale of the throughflow. Both tracers point to a north equatorial Pacific origin of the waters. The comparison of the tritium inventories in the Pacific North Equatorial Current and along the JADE transect suggests a minimum transit time of the waters across the Indonesian seaways of the order of 5 to 6 yr, corresponding to a throughflow <18 × 106 m3/s.

scholarly journals Previously unidentified Indonesian Throughflow pathways and freshening in the Indian Ocean during recent decades

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Salvienty Makarim ◽  
Janet Sprintall ◽  
Zhiyu Liu ◽  
Weidong Yu ◽  
Agus Santoso ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Indonesian Throughflow ◽  
The Indian Ocean

scholarly journals Forcing of the Indian Ocean Dipole on the Interannual Variations of the Tropical Pacific Ocean: Roles of the Indonesian Throughflow

2011 ◽  
Vol 24 (14) ◽  
pp. 3593-3608 ◽  
Author(s):  
Dongliang Yuan ◽  
Jing Wang ◽  
Tengfei Xu ◽  
Peng Xu ◽  
Zhou Hui ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Indian Ocean ◽  
Indian Ocean Dipole ◽  
Tropical Pacific ◽  
Equatorial Pacific ◽  
Indonesian Throughflow ◽  
Tropical Pacific Ocean ◽  
Equatorial Pacific Ocean ◽  
The Indian Ocean ◽  
The Tropical Pacific

Abstract Controlled numerical experiments using ocean-only and ocean–atmosphere coupled general circulation models show that interannual sea level depression in the eastern Indian Ocean during the Indian Ocean dipole (IOD) events forces enhanced Indonesian Throughflow (ITF) to transport warm water from the upper-equatorial Pacific Ocean to the Indian Ocean. The enhanced transport produces elevation of the thermocline and cold subsurface temperature anomalies in the western equatorial Pacific Ocean, which propagate to the eastern equatorial Pacific to induce significant coupled evolution of the tropical Pacific oceanic and atmospheric circulation. Analyses suggest that the IOD-forced ITF transport anomalies are about the same amplitudes as those induced by the Pacific ENSO. Results of the coupled model experiments suggest that the anomalies induced by the IOD persist in the equatorial Pacific until the year following the IOD event, suggesting the importance of the oceanic channel in modulating the interannual climate variations of the tropical Pacific Ocean at the time lag beyond one year.

scholarly journals Direct estimates of the Indonesian Throughflow entering the Indian Ocean: 2004–2006

2009 ◽  
Vol 114 (C7) ◽  
Author(s):  
Janet Sprintall ◽  
Susan E. Wijffels ◽  
Robert Molcard ◽  
Indra Jaya
Keyword(s):  
Indian Ocean ◽  
Indonesian Throughflow ◽  
The Indian Ocean

Drivers of oceanic exchange through the Indonesian Throughflow since the late 1800s – a synthesis of coral δ18O and high-resolution ocean models

2020 ◽  
Author(s):  
Sujata Murty ◽  
Caroline Ummenhofer ◽  
Markus Scheinert ◽  
Erik Behrens ◽  
Arne Biastoch ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Mixed Layer ◽  
Mixed Layer Depth ◽  
Heat Content ◽  
Phase Changes ◽  
Boreal Winter ◽  
Indonesian Throughflow ◽  
Layer Depth ◽  
Ocean Variability ◽  
The Indian Ocean

&lt;p&gt;The Indonesian Throughflow (ITF) serves as an important oceanic teleconnection for Indo-Pacific climate, altering heat and buoyancy transport from the Pacific to the Indian Ocean. Equatorial Pacific wind forcing transmitted through the ITF impacts interannual to interdecadal Indian Ocean thermocline depth and heat content, with implications for preconditioning Indian Ocean Dipole events. Yet the modulation of Indian Ocean thermal properties at seasonal timescales is still poorly understood. Here we synthesize coral &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O records, instrumental indices (El Ni&amp;#241;o Southern Oscillation (ENSO), Asian Monsoon), and simulated ocean variability (sea surface salinity (SSS) and temperature (SST), heat content, mixed layer depth) from state-of-the-art NEMO ocean model hindcasts to explore drivers of seasonal to multi-decadal variability. All coral sites are located within main ITF pathways and are influenced by monsoon-driven, buoyant South China Sea (SCS) surface waters during boreal winter that obstruct surface ITF flow and reduce heat transport to the Indian Ocean. Makassar and Lombok Strait coral &amp;#948;&lt;sup&gt;18&lt;/sup&gt;O co-varies with simulated SSS, subsurface heat content anomalies (50-350m) and mixed layer depth at the coral sites and in the eastern Indian Ocean. At decadal timescales, simulated boreal winter ocean variability at the coral sites additionally indicates a potential intensification of the SCS buoyancy plug from the mid- to late-20&lt;sup&gt;th&lt;/sup&gt; century. Notably, the variability in these coral and model responses reveals sensitivity to phase changes in the Interdecadal Pacific Oscillation and the East Asian Winter Monsoon. These results collectively suggest that the paleoproxy records are capturing important features of regional hydrography and Indo-Pacific exchange, including responses to regional monsoon variability. Such proxy-model comparison is critical for understanding the drivers of variability related to changes in ITF oceanic teleconnections over the 19&lt;sup&gt;th&lt;/sup&gt; and 20&lt;sup&gt;th&lt;/sup&gt; centuries.&lt;/p&gt;

scholarly journals Interannual Climate Variability over the Tropical Pacific Ocean Induced by the Indian Ocean Dipole through the Indonesian Throughflow

2013 ◽  
Vol 26 (9) ◽  
pp. 2845-2861 ◽  
Author(s):  
Dongliang Yuan ◽  
Hui Zhou ◽  
Xia Zhao
Keyword(s):  
Pacific Ocean ◽  
Indian Ocean ◽  
Tropical Indian Ocean ◽  
Sea Surface Height ◽  
Equatorial Pacific ◽  
Sea Surface ◽  
Indonesian Throughflow ◽  
Cold Tongue ◽  
The Indian Ocean ◽  
Southeastern Tropical Indian Ocean

Abstract The authors’ previous dynamical study has suggested a link between the Indian and Pacific Ocean interannual climate variations through the transport variations of the Indonesian Throughflow. In this study, the consistency of this oceanic channel link with observations is investigated using correlation analyses of observed ocean temperature, sea surface height, and surface wind data. The analyses show significant lag correlations between the sea surface temperature anomalies (SSTA) in the southeastern tropical Indian Ocean in fall and those in the eastern Pacific cold tongue in the following summer through fall seasons, suggesting potential predictability of ENSO events beyond the period of 1 yr. The dynamics of this teleconnection seem not through the atmospheric bridge, because the wind anomalies in the far western equatorial Pacific in fall have insignificant correlations with the cold tongue anomalies at time lags beyond one season. Correlation analyses between the sea surface height anomalies (SSHA) in the southeastern tropical Indian Ocean and those over the Indo-Pacific basin suggest eastward propagation of the upwelling anomalies from the Indian Ocean into the equatorial Pacific Ocean through the Indonesian Seas. Correlations in the subsurface temperature in the equatorial vertical section of the Pacific Ocean confirm the propagation. In spite of the limitation of the short time series of observations available, the study seems to suggest that the ocean channel connection between the two basins is important for the evolution and predictability of ENSO.

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