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Nuit agitée sur l'eau, journée agitée dans la tête des navigateurs. Après un passage nocturne mouvementé à travers le courant des Aiguilles, différentes options se dessinent dans l'Indien.

Gliders are helping unlock the secrets of the Agulhas current.

Unprecedented warm sea surface temperature (SST) anomalies were observed off the west coast of Australia in February-March 2011. Peak SST during a 2-week period were 5°C warmer than normal, causing widespread coral bleaching and fish kills. Understanding the climatic drivers of this extreme event, which we dub "Ningaloo Niño", is crucial for predicting similar events under the influence of global warming. Here we use observational data and numerical models to demonstrate that the extreme warming was mostly driven by an unseasonable surge of the poleward-flowing Leeuwin Current in austral summer, which transported anomalously warm water southward along the coast. The unusual intensification of the Leeuwin Current was forced remotely by oceanic and atmospheric teleconnections associated with the extraordinary 2010-2011 La Niña. The amplitude of the warming was boosted by both multi-decadal trends in the Pacific toward more La Niña-like conditions and intraseasonal variations in the Indian Ocean.

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

After a hideous night bashing across the Agulhas Current, the Volvo Ocean Race fleet has now reached a road block. It is the windless trough between the two low-pressure systems, which have threatened, but not yet evolved into one. It is now a race to get through the light and fluky airs of the trough and reach the new northerly breeze of the second front.

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.

New Ocean Current Found Off the Coast of Africa.

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

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?

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.

The southeastern Indian Ocean (SEIO) exhibits prominent decadal variability in sea surface salinity (SSS), showing salinity decreases during 1995-2000 and 2005-2011 and increases during 2000-2005 and after 2011. These salinity changes are linked to the Indo-Pacific climate and have impacts on the regional marine environment. Yet, the underlying mechanism has not been firmly established. In this study, decadal SSS variability of the SEIO is successfully simulated by a high-resolution regional ocean model, and the mechanism is explored through a series of sensitivity experiments. The results suggest that freshwater transport of the Indonesian throughflow (ITF) and local precipitation are two major drivers for the SSS decadal variability. They mutually cause most of the variability, with a generally larger contribution of precipitation. Other processes, such as evaporation and advection driven by local winds, play a minor role. Further analysis shows that the decadal precipitation in the SEIO is mainly associated with the decadal variability of Ningaloo Niño. Ocean dynamic processes significantly modify the relationship between SSS and precipitation, greatly shortening their lag time. The changes in both volume transport and salinity of the ITF water can cause large salinity changes in the SEIO region. Although local wind forcing gives rise to considerable changes in evaporation rate and ocean current advection, its overall contribution to decadal SSS variability is small compared to local precipitation and the ITF.

Giant Ocean Vortex Linked to Monsoon.

The mysteriously rich diversity of life on the isle of Madagascar might have arrived there in part on 'floating islands' carried by ocean currents, researchers now say.

It is a nervous time for Team Telefónica's navigator Andrew CAPE having "rolled the dice" and laid his bet on a course that has placed his team in the lead, but also at one end of a major split in the fleet.

A new study published in the international journal Nature Communications has revealed how Western Australia's coral reefs have been affected by changing ocean currents, rising sea surface temperatures and sea level variability.

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?

How Missing Jet's Debris Could Have Floated to Réunion.

How Missing Jet's Debris Could Have Floated to Réunion.

What happened to MH370? Prediction markets might give us the answer.

What happened to MH370? Prediction markets might give us the answer.