Research published this week shows regional climate variability caused an “unusual” period in which some of New Zealand’s glaciers grew bigger, while glaciers worldwide were shrinking.
News of these findings came just a few days after the Deep South National Science Challenge announced funding of about $2 million for five new research projects to help New Zealanders better understand their future climate.
The funding is part of the Deep South National Science Challenge which is tasked with enabling New Zealanders to adapt, manage risk and thrive in a changing climate.
This funding round is focused on the potential impacts and implications of climate change for New Zealand to support planning and decision-making around extreme weather events, drought, changes in typical weather patterns and sea level rise.
Central to the challenge is strengthening the links and interactions with the New Zealand Earth System Model. This numerical model will simulate current climate and make projections of future climates with different scenarios of future global greenhouse gas emissions.
Ultimately the Deep South Challenge will help advance understanding of Southern Hemisphere influences on the global climate and give New Zealanders a greater level of certainty in the face of a changing climate.
The new projects include incorporating climate change impacts in land-use suitability.
The others are:
• The impact of climate change on New Zealand’s frozen water resources – developing improved future projections of glacier and snow melt
• National hydrological and water resource impacts of climate change – a study on the potential effects of climate change on the hydrological cycle
• Robust adaptation decision-making under uncertainty in the water sector
• Supporting decision making through adaptive tools in a changing climate
While the projects are funded by the Deep South Challenge, they are undertaken by researchers across a range of institutions including Victoria University, NIWA, Scion, Landcare Research, University of Otago, Plant & Food Research, AgResearch and GNS Science,.
These projects will be delivered alongside the Engagement and Vision Mātauranga programmes that will connect the science to the experiences, needs, and decision-making processes of New Zealanders.
The new projects represent the development of the final part of the challenge, the Impacts and Implications Programme.
The Deep South National Science Challenge is one of 11 Ministry of Business, Innovation and Employment-funded initiatives aimed at taking a more strategic and collaborative approach to science investment.
For more details of the new research projects, visit the Deep South website here.
The scientific journal Nature Communications has published the findings from the study of glacial changes, funded by a core NIWA project ‘Climate Present and Past’.
It was conducted by scientists from Victoria University of Wellington and the National Institute of Water and Atmospheric Research (NIWA) who used computer modelling to understand the drivers of glaciers.
At least 58 New Zealand glaciers advanced between 1983 and 2008, with Franz Josef Glacier advancing nearly continuously during this time.
“Glaciers advancing is very unusual—especially in this period when the vast majority of glaciers worldwide shrank in size as a result of our warming world,” says lead-author Associate Professor Andrew Mackintosh from Victoria’s Antarctic Research Centre.
“This anomaly hadn’t been satisfactorily explained, so this physics-based study used computer models for the first time to look into it in detail.
“We found that lower temperature caused the glaciers to advance, rather than increased precipitation as previously thought. These periods of reduced temperature affected the entire New Zealand region, and they were significant enough for the glaciers to re-advance in spite of human-induced climate change.”
Associate Professor Mackintosh says the climate variability, which includes the cooler years, still reflects a climate that has been modified by humans.
“It may seem unusual—this regional cooling during a period of overall global warming—but it’s still consistent with human-induced climate change. The temperature changes were a result of variability in the climate system that’s specific to New Zealand.
“New Zealand sits in a region where there’s significant variability in the oceans and the atmosphere—much more than many parts of the world. The climate variability that we identified was also responsible for changes in the Antarctic ice sheet and sea ice during this period.”
Associate Professor Mackintosh says the researchers found New Zealand glaciers that advanced had certain characteristics, including specific elevation and geometry.
Franz Josef Glacier actually regained almost half of the total length it had lost in the 20th century but Tasman Glacier, New Zealand’s largest glacier, continued to retreat. New Zealand glaciers accordingly lost mass overall over the study period.