A study led by the University of Otago’s Dr Christian Ohneiser has revealed the region may have experienced decades of reduced rainfall — or a "mega drought" — thousands of years ago.
Published in scientific journal Nature Communications, it suggests drought may become more common in the region if the world keeps warming.
Ohneiser and his co-authors analysed a 6.1-metre sediment core taken from the picturesque lake in 2015.
In a "paleoclimate reconstruction", their analysis of the core shows that during a period called the ‘Younger Dryas’ — between about 12,900 and 11,700 years ago — New Zealand’s climate was warmer than it is now.
The findings enable a useful comparison between the climate then and what it could become in a few decades if the world keeps warming, the authors say.
"In this region, the Younger Dryas was warmer than today, which indicates persistent drought conditions may return as the climate warms."
They note that until about 10,000 years ago, Lake Hayes was part of an enlarged Lake Whakatipu, so the sediment core may have captured a better record of the wider Whakatipu Basin than it does today.
