New Zealand's renowned glaciers continue to lose snow and ice, as revealed by the latest annual end-of-summer snowline survey conducted by NIWA. The 2023 survey, marking the 46th year of collaboration between NIWA, Victoria University of Wellington, and the Department of Conservation, captures aerial images of over 50 Southern Alps glaciers each year to track their changes, according to a National Institute of Water and Atmospheric Research media release earlier this month.
NIWA, @WgtnUniResearch, @docgovtnz & @MonashUni flew over 50 South Island glaciers last week for the annual end-of-summer snowline survey, revealing a continued loss of snow & ice for New Zealand’s glaciers.
— NIWA (@niwa_nz) March 31, 2023
Full story here 👉 https://t.co/jdoGhuwpqv
📸 Rebekah Parsons-King pic.twitter.com/4g3tLW3yvk
South Island's hot summer exacerbates glacial retreat
NIWA Principal Scientist Dr. Andrew Lorrey, who coordinates the survey, stated that while there is variability in the health of New Zealand's glaciers, the trend of ice loss from previous years continues.
"With the South Island's incredibly hot summer, we were expecting snowlines to be very high. The picture from this survey was a mixed bag. Snowlines were clearly visible across some glaciers while others had exposed ice from prior years laid bare up to the mountain top," according to Dr. Lorrey.
Walking off Brewster Glacier, Mt Aspiring National Park w @AMacGlac & @bexparsonsking after filming for a @niwa_nz piece on monitoring glaciers. There is a multicentury ice recession history here, but a lot has gone in recent decades. The mountains are experiencing fast changes. pic.twitter.com/LWfQxTuAHY
— Drew Lorrey (@DLorrey) April 1, 2023
Implications for tourism and meltwater supply
The ongoing loss of snow and ice from these glaciers not only poses a threat to the glaciers themselves but also has significant consequences for the people who rely on them for tourism and meltwater supply during periods of drought.
Dr. Lorrey expressed concern over these potential impacts, stating, "This trend is worrisome – not only do we risk losing the glaciers and our intimate relationship with them completely, but it will also affect the livelihoods of people who rely on these natural wonders for tourism, as well as flow on effects from decreased meltwater during periods of drought."
Iconic glaciers such as Fox and Franz Josef markedly retracted
Professor Andrew Mackintosh from Monash University, who joined this year's flight, observed that the Southern Alps glaciers have retracted significantly since he last participated in the end-of-summer snowline flight.
"I was shocked by the state of the small low elevation glaciers, which have largely disappeared. Iconic glaciers such as Fox and Franz Josef have retreated markedly. The scale of retreat is confronting, even to a glaciologist. It emphasises the urgency of slowing climate change because the impacts are going to become increasingly costly and hard to avoid," said Professor Mackintosh.
Urgent need to address climate change to preserve glacial ecosystems
As the scientific results from this year's glacier and snowline survey will be available later this year, these initial findings underscore the urgency of addressing climate change to preserve New Zealand's glaciers and their surrounding ecosystems. The ongoing ice loss trend, as highlighted by NIWA's annual survey, serves as a crucial reminder of the need to take proactive steps towards mitigating the effects of climate change on these fragile and vital natural resources.