Glaciers continue to shrink this year - NIWA

The annual end-of-summer snowline survey of more than 50 South Island glaciers has revealed continued loss of snow and ice.

Each year, the NIWA monitoring programme evaluates many glaciers and the altitude of the snowline to see how much of the previous winter’s snow has remained covering each glacier.

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°C.

NIWA Principal Scientist Dr Andrew Lorrey, who leads the project, says that many of New Zealand’s glaciers are suffering thanks to exceedingly warm summer temperatures, exacerbated by a marine heatwave.

"What we’re seeing is a clear retreat, which is no doubt thanks to climate change. 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 of decreased meltwater during periods of drought. It also emphasises the urgency of slowing climate change because the impacts are going to become increasingly costly and hard to avoid," says Dr Lorrey.

Dr Lauren Vargo from Victoria University of Wellington says the retreat that we're seeing is due to the majority of New Zealand’s glaciers losing mass most years over the past decade.

"Based on what I saw during the 2022 survey, it looks like our glaciers have struggled compared to last year. The snowline elevations this year were high, meaning much of the winter snow 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".

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