Bigger and more frequent monster waves in Southern Ocean threaten to gobble up coastlines amid climate change
- Study finds that global warming will trigger larger and more frequent extreme waves over the next 80 years in the Southern Ocean
- The extreme wave increases could cause potential damage to Australian, Pacific and South American coastlines by the end of 21st century
When the HMNZS Otago met some stretching more than 20m high in 2017, the 1900-tonne offshore patrol vessel came close to capsizing, with 75 people on board.
The following year, the largest wave ever recorded in the Southern Hemisphere – a 23.8m giant that formed in the thick of a huge, deep storm – was measured by a buoy moored off Campbell Island.
During the depths of winter, these waves were enormous, averaging more than 5m, regularly exceeding 10m – and sometimes likely reaching more than 25m, or the equivalent height of 16 cars stacked on top of each other.
Anything more than 20m high is highly hazardous to vessels – waves that climbed to 14m forced the HMNZS Wellington to turn around partway to the Subantarctic islands in 2014 – and ships tend to negotiate heavy seas by sailing head-on into the direction the waves are coming from.