First picture of giant whirlpool off Wild Coast has scientists pondering

A 30m-wide whirlpool seen in the ocean off the Wild Coast could be linked to climate change.

Photographed on August 17 by Green Scorpion Robert Stegmann during a routine SAPS air patrol, the images show one and possibly even two of the spinning holes in the ocean.

Whirlpools are dangerous for ocean users and this one was 245m off Rame Head point, East London Museum principal natural scientist Kevin Cole said.

The plane was 350m above the phenomenon.

“This is the first photographic evidence we have of a whirlpool, though there have been numerous anecdotal stories about whirlpools and super waves off the Wild Coast.

“If anyone is able to send us information about more of these, please call the museum on 043-743-0686 or email kcole@elmuseum.za.org

“We have heard of anomalies along the Wild Coast and a number of mysterious shipping disasters, such as the sinking of the Waratah, so these photographs are important,” Cole said.

Cole said the whirlpool was reasonably large, and was close to shore and contained a lot of energy.

He was investigating whether the volatile, fast-flowing Agulhas current had come close inshore and connected with a longshore drift flowing in the opposite direction.

The energy displaced by the two opposing forces would caused a “violent vortex which evolved into a spinning whirlpool” .

It was possible that the vortex posed a real threat to small craft, divers or swimmers.

He said the event took place against a background of changing ocean current behaviour in a shifting climate.

However, Professor TommyBornman, a research leader at the SA Environment Observation Network and coastal ecology expert, did not think the Agulhas was directly involved.

“Whirlpools form when water moving in two directions come into contact,” he said.

Initially he suspected a strong longshore current (moving towards Durban) had clashed with the Agulhas (moving towards East London) which had come close to the shore.

“When opposing currents meet they are known to generate freak waves and strong currents.

“It is possible that with exceptionally strong winds, the Agulhas has come in closer and the longshore drift has also become exceptionally strong.”

However, after a closer inspection of the photographs, he said: “I don’t think the Agulhas current is involved — too close inshore and way too shallow at a 30m depth.

“This is clearly the result of a very strong longshore current coming up against a strong rip current.”

He had done a lot of research on powerful eddies, such as those which appear in the warm Mozambican channel and form the Agulhas current and give it a sudden convulsion, known as the Natal pulse.

“Some of the eddies formed by the Agulhas are 100km wide. They are not known to create whirlpools but they could. We have never seen it before.”

He said the warming climate and related change in the state of the oceans had caused the Agulhas to heat up.

There was debate in the scientific community how this played out.

“As it heats up it can meander or broaden. We are seeing more extreme weather and more of storm surges and storm winds.” 

He and Cole spoke of a new discovery of a huge cyclonic cold core eddy happening in the south off Antarctica.

A crew of scientists aboard SA Agulhas II took samples of this huge upwelling of cold water a month ago and were “very excited” at what they discovered.

He said the Eastern Cape coastline would continue experiencing more upwellings of easterly winds and sudden swings in water temperature from 26°C to 12°C and then back up to 27°C, causing fish to go into thermal shock and wash up dead.

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