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The effect of tides on the Indonesian Throughflow (ITF) is explored in a regional ocean model of South East Asia. Our model simulations, with and without tidal forcing, reveal that tides drive only a modest increase in the ITF volume, heat and salt transports toward the Indian Ocean. However, tides drive large regional changes in these transports through Lombok Strait, Ombai Strait and the Timor Sea, and regulate the partitioning of the ITF amongst them. The effect of tidal mixing on the salinity and temperature profiles within the Indonesian Seas drives a small decrease in the heat and salt transports toward the Indian Ocean in all three exit passages. In contrast, the tidal residual circulation due to the interaction between the tides and the topography and stratification (including the effects of tidal mixing on the circulation) leads to a large decrease in the transports toward the Indian Ocean through the Lombok and Ombai straits, but a large increase through the Timor Sea. Hence, the small net contribution from tides to the ITF's volume, heat and salt transports is due to a compensation between large, but opposing tidal residual transports at the combined Lombok and Ombai straits and in the Timor Sea. Our results indicate that explicit representation of tides, often missing in Earth system models, is necessary to accurately capture the ITF's pathway and so the tracer transport from the Pacific into the Indian Ocean.

Scientists have identified a new mechanism to account for the drastic aridification in eastern Africa over the past two million years, with likely implications for understanding the evolution and dispersal of our early human ancestors.

The oxygen minimum zone has a significant effect on primary production, marine biodiversity, food web structure, and marine biogeochemical cycle. The Arabian Sea oxygen minimum zone (ASOMZ) is one of the largest and most extreme oxygen minimum zones in the world, with a positional decoupling from the region of phytoplankton blooms. The core of the ASOMZ is located to the east of the high primary production region in the western Arabian Sea. In this study, a coupled physical-biogeochemical numerical model was used to quantify the impact of ocean circulation and settling of particulate organic matters (POMs) on the decoupling of the ASOMZ. Model results demonstrate that the increased (decreased) dissolved oxygen replenishment in the western (central) Arabian Sea is responsible for decoupling. The oxygen-rich intermediate water (200-1,000 m) from the southern Arabian Sea enters the Arabian Sea along the west coast and hardly reaches the central Arabian Sea, resulting in a significant oxygen replenishment in the western Arabian Sea high-productivity region (Gulf of Aden) but only a minor contribution in the central Arabian Sea. Besides that, the POMs that are remineralized to consume central Arabian Sea dissolved oxygen comprises not only local productivity in winter bloom but also the transport from the western Arabian Sea high-productivity region (Oman coast) in summer bloom. More dissolved oxygen replenishment in the western Arabian Sea, and higher dissolved oxygen consumption and fewer dissolved oxygen replenishment in the central Arabian Sea could contribute to the decoupling of the ASOMZ and phytoplankton productive zone.

New GEOMAR study investigates decadal variations of Agulhas leakage and their influence on the Gulf Stream system.

Drops locked inside rock offer clues to modeling Earth's climate and ocean circulation.

Giant Ocean Vortex Linked to Monsoon.

UM Rosenstiel School Agulhas Current study has important implications for global climate.

Gliders are helping unlock the secrets of the Agulhas current.

Australian scientists have identified causes of a rapid warming in the upper subtropical oceans of the Southern Hemisphere.

Natural variations in the warming and cooling cycles of the globally important Agulhas ocean current core region have been revealed in a new study of a Madagascar corals led by The University of Western Australia including researchers from the ARC Centre of Excellence for Coral Reef Studies and published in Nature Scientific Reports.

Here's a simple backyard science experiment for you to try, which has global implications.

Aircraft debris looks like it's from MH370 - now can we find the rest?

Aircraft debris looks like it's from MH370 - now can we find the rest?

A current affair: the movement of ocean waters around Australia.

New Ocean Current Found Off the Coast of Africa.

Why deeper insights into the Agulhas Current can shed light on climate patterns.

Powerful computer simulations are revealing new insights into water exchanges between the Red Sea and the Gulf of Aden.

Our oceans and the complex "conveyer belt" system of currents that connects them play an important role in regulating global climate. The oceans store heat from the Sun, and ocean currents transport that heat from the tropics to the poles. They release the heat and moisture into the air, which moderates climate nearby. But what happens if part of that conveyer belt jams?

Long-distance drifting of seaweeds driven by ocean currents is an ideal model for exploring population-level genetic connectivity and phylogeographic structure. In the Indo-Pacific convergence region, we integrated phylogeographic and ocean current data and Lagrangian particle simulations to explore how the ocean currents contributed to the biogeographical patterns and population genetic connectivity of Sargassum polycystum. The oceanographic transport and direction of gene flow was in line with contemporary ocean currents. The S. polycystum geographical dispersal from glacial refugia homogenized the footprint of genetic divergence. The multidisciplinary intersection provides insights into the evolutionary history and biogeographic conservation of tropical seaweeds in the Indo-Pacific convergence region.