Waves are forecast to become larger and more powerful and to shift direction if the climate continues to warm at its current rate, with southern Australia among the regions to be hardest hit globally, new research says.

The study, led by scientists from Griffith University and published in Nature Climate Change on Tuesday, comes as meteorologists forecast a "quite rare event" later this week as a potentially damaging swell hits eastern Australia.

A monster wave in January 2015 that washed a woman off Nobbys breakwall in Newcastle. Credit:Cordelia Troy

Using about 150 model simulations, the researchers found about half the world's coastline was "at risk from wave climate change" by the final two decades of this century if greenhouse gas emissions remained at their current "business-as-usual trajectory".

The wave changes, driven primarily by strengthening winds "might potentially exacerbate or even exceed in some coastal regions, impacts of future sea-level rise", the paper said.