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Australia and Timor-Leste to sign deal on contentious gasfield.

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.

The Lombok Strait (LS), Ombai Strait (OS), and Timor Passage (TP) are three major outlets of the Indonesian Throughflow to the Indian Ocean. Here, sources and pathways of the LS, OS, and TP outflows are explored by a Lagrangian particle tracking analysis based on a ~3 km regional ocean model simulation. The Makassar Strait transport contributes to ~80%, ~75%, and ~45% of the LS, OS, and TP outflows, respectively. However, ~41% and ~19% of the TP and OS outflows stem from the Lifamatola Passage, which largely feeds the upper and intermediate layers of the outflows. The role of Karimata Strait is quite limited and restricted to the upper layer. It takes 1-2 years and 2-6 years for the Makassar Strait water to reach the OS and TP, respectively, whereas the Lifamatola Passage water passes through the OS (2-6 years) and TP (3-9 years) on a prolonged transit time. In the Banda Sea, the western boundary current is the main pathway toward the OS, while the waters to the TP tend to take a basin interior route.

Deeper waters at remote Ashmore Reef off the Western Australian coast could be acting as a refuge for sea snake species not seen in shallow waters for more than a decade, new research led by the Australian Institute for Marine Science (AIMS) indicates.

With marine heatwaves of varying severity identified in Australian waters over the summer, a new study of a remote coral reef in the north-west has found that they can recover from bleaching events caused by heatwaves, and other disturbances, as long as there is enough time.