'Shattered': NZ glaciers shrink due to global warming

New Zealand's glaciers are suffering from "enduring ice loss" as a result of global warming, according to a government environmental body.

The National Institute of Water and Atmospheric Research (NIWA) says survey flights show the nation's glaciers appear "smashed and shattered due to enduring ice loss".

The scientific agency has been carrying out the surveys since the 1970s to analyse snowline elevation and the state of the glaciers.

"Overall, the snowline has been rising and in the most recent years we're seeing that rise accelerate, so we're experiencing a continued trend of glacial ice loss," said Dr Andrew Lorrey, NIWA's principal scientist for climate and environmental applications.

NIWA scientists even noted that in the latest survey, a glacier that had not been flown over since 2018 is now two-thirds of the size it was then.

The scientists linked the receding glaciers to rising temperatures in New Zealand, which in the past 10 years has experienced seven of its warmest years since records began.

Last year was the second-warmest year on record, a trend that followed the rest of the world, with 86 per cent of the planet recording above-average temperatures in 2023.

"Even if we got a few cooler seasons, they wouldn't be enough to undo the damage that's already been done," said Lorrey, insisting on the need to "tackle the issue of rising greenhouse gases if we are to save our glaciers from melting away".

Glaciers are important sources of meltwater, supporting stream habitats and providing nutrients to lakes, rivers and oceans, as well as feeding hydroelectric lakes, impacting the availability of renewable energy.

New Zealand's glaciers are estimated to contribute about NZ$100 million ($A92 million) annually to the country's economy through tourism.