Farmers need to adapt for a drier future as once-in-a-lifetime events like the North Island drought become closer to the norm, a top climate scientist warns.
James Renwick, Associate professor of physical geography at Victoria University, said global warming was the only explanation for the current drought, which he described as "an exceptional event".
"It's probably the first time in 50 years that it's been this dry over this much of the country," he told TVNZ's Q+A programme today.
He warned conditions as dry as this summer's would become more common, as average temperatures increased due to climate change.
A dry summer now would be closer to the norm in 50 to 100 years' time, while a one-in-50 year event like the current drought would be a one-in-20 to one-in-25 year event by the middle of the century.