The rapid thinning of the Antarctic glaciers could last for centuries, according to a new study from Victoria University.
Its Antarctic Research centre has presented the first recorded evidence that the process has already taken place in the past - 7000 years ago.
It provides a new insight into parts of the Antarctic ice sheet that are currently thinning because of a warming ocean.
Deputy director Andrew Mackintosh said the research was a wakeup call that retreat of the ice sheet could happen very quickly and continue for a thousand years.
The discovery was important for understanding the current thinning process caused by warmer seas, he said.
He hoped it would help with predicting rising sea levels.