Where the westward South Equatorial Current encounters the northeast coast of Australia, part of it continues northward and becomes part of the Indonesian Throughflow, but the larger part shears off to the south and becomes the southward East Australia Current. The EAC is a “western boundary current”, a feature which occurs around the world on several prominent east coasts such as the United States (with the Gulf Stream) and Japan (with the Kuroshio). It is a feature of the Coriolis effect that these currents which move poleward away from the equator along the east coasts of land masses, are narrow and rapid (up to 4 kts/7.4 km/h).
The current system around Australia.
The East Australia Current flows into the rapidly warming Tasman Sea, and is suspected to be a main driver of the warming there. Study is just beginning on this issue, so there are no clear conclusions yet. But the EAC appears to be gaining strength, with a larger volume of warm water being transported from the equatorial current south to the temperate zone. In addition to current measurements, which are now being made, tropical species of jellyfish are being observed farther south, carried by stronger flows of warm water.
The EAC and Tasman Sea to the south.
Though this is an as-yet somewhat murky aspect of ocean science, a strengthening East Australia Current leading to a rapidly warming Tasman Sea is consistent with the global pattern, observed elsewhere, of increased poleward transport of heat from the tropics, via ocean currents and weather patterns (such as hurricanes).
Southeast Australia (including the Tasman Sea), increasingly a hotspot in recent decades.
Duuuuuuuuuuuude. Turtles riding the EAC. (The folks behind Finding Nemo did their homework, in terms of the physical environment and biology.)
Be brave, and be well.
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