Like rivers of ice in retreat, melting glaciers are seen as a symbol of climate change. But how much of their change can actually be attributed to it?
It’s a question that’s led glaciologist Dr Lauren Vargo into a life on ice studying the frozen world – a world she’s now introducing to the next generation of potential scientists. “One of the great things about glaciers, and one of the reasons I started studying them, is they’re such a good visualisation of climate change,” Vargo explains. “They’re often pointed to as this impact of climate change – we see the glacier melting – but I think it’s really important to be able to say that we know that this melt was due to climate change or we know some percentage of this melt was due to climate change.”
A research fellow based at Victoria University of Wellington’s Antarctic Research Centre, Vargo has a special interest in measuring the impact of climate change on glaciers. She began asking the question as a focus of her PhD, which she completed in 2019, for which she developed a workflow to quantify climate change’s role in glacial change for New Zealand’s Brewster and Rolleston glaciers.
Her PhD research included monitoring changes in glaciers by drawing on Niwa’s end-of-summer-snowline survey, which has captured photos of 50 New Zealand glaciers annually since 1977, and measurements made during trips to the glaciers to measure their total gain or loss of ice over year. The research determined that the extreme glacial melting seen in 2018, when New Zealand experienced a marine heatwave, was made at least 10 times more likely due to climate change.
Having secured $360,000 from the Marsden Fund, administered by the Royal Society Te Apārangi, Vargo is now starting a project where she’ll be asking the question of how climate change is affecting glaciers on a global scale. Alongside other international researchers, she will use computer models to simulate glacier mass change in scenarios where greenhouse gases are at both a third of current levels and at today’s levels (in a world without climate change, and in a world with it). It will look at the impact of climate change on glacial melt in 230 glaciers globally, as well as project future changes as temperatures rise.
Being able to attribute how much glacial melt is due to climate change is important for communicating humans’ impact on these frozen environments, she says, but the work informs a wider picture. “Glaciers have contributed more to sea level rise than the ice sheets melting so far,” she says. “They’re also really important for water resources – maybe a little more so in other parts of the world – but in New Zealand, glaciers are also important for tourism and they have this cultural importance.”
It begs a question: does working in this field and seeing such dramatic changes in glaciers frighten her? “It’s strange because when you do the day to day, it’s almost exciting to see these big changes. If we were monitoring glacier change and they weren’t changing at all, you’re showing that nothing’s happening; you don’t get those kinds of dramatic results. But then once you take a step back and think about what these changes in the glaciers mean and the bigger picture of climate change, yeah, I think it makes me worry about climate change maybe more than people who don’t think about it every day.”
Vargo spends most of her working life in the office, but getting out on the ice to conduct fieldwork is an important element of the job and one that she loves. It was part of what motivated her to co-found Girls* on Ice Aotearoa around three years ago, alongside Dr Ruzica Dadic, a fellow glaciologist and climate scientist who was then a research fellow at the Antarctic Research Centre. (The asterisk denotes that girls include female-identifying, non-binary and intersex students.)
The programme falls under the umbrella of Inspiring Girls* Expeditions, a programme that began in the US more than 20 years ago and provides opportunities for teenage girls to go on expeditions where they get involved with scientific fieldwork, art and outdoor adventure.
Vargo was an instructor on a Girls* on Ice Alaska expedition last year, where a group spent almost two weeks living next to a glacier, learning how it works, and using art to observe it and the wider environment. In January 2024, she’ll help lead a group of 15- and 16-year-old girls on the first New Zealand expedition, where they’ll be based at Mount Ruapehu. While there, they plan to hike to its glaciers, learn about the alpine environment, conduct science experiments and create art pieces.
Vargo herself wasn’t raised among mountains and glaciers – although it snowed heavily during winters in Cleveland where she grew up. She loved spending time outdoors, but admits she wasn’t that interested in science until she took an environmental geology class as part of undergraduate study at the College of Wooster in Ohio.
“I realised that there is this kind of science where you can learn about the world around you and you can be outdoors for some of the time,” she recalls. “And in the last year of my undergrad, I got to do some work in Alaska studying how glaciers have been changing on longer time scales, over the last few hundreds of years, and that’s how I got into studying glaciers – almost more as a way to study climate change than kind of studying the glaciers themselves.”
As part of her Master’s at the University of New Mexico, she spent some time carrying out fieldwork high in the Andes, studying signs of past glacial activity, before working at the Los Alamos National Lab, using computer models to explore ice sheet change. While there, a mentor talked about how he’d done his PhD in Wellington – and recommended she do the same. She’s lived in Wellington since arriving to undertake her own PhD in 2016, and these days has a New Zealand-born partner and an application for permanent residency in train.
At the beginning of this year, Girls* on Ice Aotearoa co-founder Dadic moved to Davos, Switzerland, where she heads the Snow and Atmosphere Research Unit at the WSL Institute for Snow and Avalanche Research SLF (the Swiss Federal Institute for Forest, Snow and Landscape Research). However, she continues to work on scientific projects with Vargo, and one of Dadic’s students has stepped in to help with Girls* on Ice Aotearoa. Dadic says she and Vargo knew the programme would be time consuming, but actually getting it underway has required more work than they thought. But Vargo is someone who “gives a damn”, Dadic says, and is determined to make an impact through science.
She describes Vargo’s PhD work to quantify the impact of climate change on glaciers as “groundbreaking” – important not just in the field of glaciology, but for communicating to society the toll human activities are taking on our frozen environments. “I think something that gets lost when you have nice people who do a lot of outreach, is that her scientific contribution is just as valuable,” says Dadic. “She’s foremost a scientist and she uses being a scientist to help improve society.”
