The wild waters to the south of New Zealand have played host to record-breaking swell, with a buoy moored in the Southern Ocean picking up the largest wave ever recorded in the Southern Hemisphere.

"This is a very exciting event and to our knowledge it is largest wave ever recorded in the Southern Hemisphere," says Dr Tom Durrant, Senior Oceanographer at MetOcean Solutions, the science consultancy behind the finding. "Our own previous record was one year ago when we measured a 19.4 m (64 ft) wave, and before that in 2012 an Australian buoy recorded a maximum individual wave of 22.03 m (72 ft)."

The 23.8 m (78 ft) wave came crashing down in the midst of a ferocious storm with winds in excess of 65 knots. That storm also brought a significant wave height of 14.9 m, another record for the Southern Ocean, although short of the world record 19 m (62.3 ft) measured in the North Atlantic during 2013.

Significant wave height is a standard measurement used by the World Meteorological Organization to account for one-off waves that can be difficult to measure. Instead, they offer a more general indication of the swell by relying on an approximate average of the highest third of measured waves.

While impressive enough, it is entirely likely that this 23.8-meter wave was eclipsed by others in the area, with the storm system probably triggering even larger waves that rolled by undetected.

"It is likely that the peak heights during this storm were actually much higher, with individual waves greater than 25 m (82 ft) being possible as the wave forecast for the storm show larger wave conditions just north of the buoy location," says Durrant. "Also, to conserve battery during the one year deployment, the solar-powered buoy samples the waves for just 20 minutes every 3 hours then sends the data via a satellite link."

Those 25-meter waves would be larger than any surfed by a human, exceeding the 24.28 m (80 ft) monster that Brazil's Rodrigo Koxa rode to that title in Portugal last year. But they still wouldn't reach the heights of the biggest wave recorded anywhere in the world, a title still held by the 30.5 m (100-ft) tsunami that followed a 7.7 magnitude earthquake in Alaska in 1958.

However, the huge wave is still significant in terms of science. The Southern Ocean occupies 22 percent of the global ocean and events there can have a ripple effect on conditions around the planet. Durrant says, for instance, that surfers in California will benefit from the energy created by this storm in around a week's time.

"This is exactly the sort of data we were hoping to capture at the outset of the program," says MetOcean Solutions General Manager Dr Peter McComb, who led the deployment of the buoy. " We know that the speed of these storms plays an important role in the resultant wave climate and that has great relevance under both the existing and climate change scenarios."