In a decade, New Zealand’s important glaciers will be gone

Principal scientist Dr Andrew Lorrey, who leads the project, said many of New Zealand’s glaciers were suffering due to “exceedingly warm summer temperatures, exacerbated by a marine heatwave.”

“In a decade, we predict that many of our beloved and important glaciers will be gone. This will have far-reaching impacts, such as altering our beautiful landscape, affecting the livelihoods of people who rely on these natural wonders for tourism, and flow on effects from decreased meltwater during periods of drought,” he said.

“It also emphasises the urgency of slowing climate change because the impacts are going to become increasingly costly and hard to avoid.”

There were just under 3000 glaciers in New Zealand, with most of them located in the South Island.

He said up to 40 per cent of the 50 glaciers being monitored since the 1970s would be gone within a decade.

He said the smaller glaciers in the lower southern and northern areas of the Southern Alps were rapidly dwindling, including Caroline Peak in the Merrie Ranges, Mt Ella, Mt Browning and Mt Franklin in North Canterbury.

The most well-known glaciers, Franz Josef and Fox, were at a higher elevation, so some of them would remain, but already they were less accessible than a decade ago. The only way to access the glaciers now is by air, after it was deemed too dangerous to walk onto the ice in 2012. The Government gave $3.9 million fund for upgrades of walking tracks and to help diversify South Westland’s tourism industry.

“It will impact tourism in a number of ways. Access to the glaciers will get more remote, and you will have to go further and further up to see the glacier.”

Co-chairman of the Glacier Country Tourism Group Richard Benton said the group had started working on marketing campaigns to highlight other activities tourists could do in Franz Josef and Fox Glacier like walking tracks, fishing and visiting the country’s largest kiwi incubation centre.

“The glaciers will always be an important magnet for the region, but we want to make sure tourists know that there are lots of reason to come and stay here,” he said.

Lorrey said tourist activities like tramping near the glaciers might get dangerous as the landscape around would be instable and boating in lakes under a glacier might also be dangerous as there are chances an ice wall might collapse into the lake causing a local tsunami.

He added that loose sediment near the Tasman Glacier, located in the Aoraki/Mount Cook National Park, collapsing into the Tasman Lake have blocked some pathways used by trampers to get up the mountain.

Last week, scientists from Niwa, Victoria University of Wellington, and Department of Conservation took thousands of aerial photographs of glaciers. Some are used to build 3D models that track changes in the ice volume.

The long-term aerial survey provides a valuable evidence timeline, stretching back to 1977, and visually shows how much glaciers have retreated. Since the snowline survey began, the global climate has warmed by around 1.1 degree Celsius.

Lorrey said there was a “clear retreat, which is no doubt thanks to climate change.”

“We were expecting the snowlines to be high because of the warm weather we’ve had and sadly, our instincts were confirmed,” Lorrey said.

“A couple of glaciers, such as Brewster (West Coast), has snowlines at least as high as in 2016, which was in our top five high snowline years. The surface of the Volta Glacier (Mount Aspiring National Park) also showed a lot of snow and ice accumulation layers from prior years, meaning it’s probably a bad year when we can see all those “book pages” from the past being exposed.”

Dr Lauren Vargo, of Victoria University, said the majority of New Zealand’s glaciers lost mass most years over the past decade.

“From what we saw on the snowline survey, most glaciers had reasonably high snowlines, showing that they lost mass this year. But what was more striking to me is how much smaller and more skeletal so many of the glaciers are becoming,” Vargo said.

Niwa climate scientist Gregor Macara said there was a “noticeable difference” on this year’s survey.

“Based on what I saw during the 2022 survey, it looks like our glaciers have struggled compared to last year,” Macara said.

“The snowline elevations this year were high, meaning much of the winter snows had melted, leaving a lot of glacial ice exposed. It appears to be yet another poor year for our ice, continuing the trend from recent years, and it is disheartening to see the ongoing decline in extent of the glaciers we monitor.”

Niwa’s work estimates that more than a third of the ice volume has been lost from the Southern Alps since the survey began.

The scientific results from this year’s survey will be known later this year.