Sunday, 4 February 2024

Antarctica's Denman Glacier is one of the most remote places on Earth. This is what it's like to work there.

 Extract from ABC News

The vast Denman Glacier snakes 110 kilometres across East Antarctica, but what lies beneath it?(Supplied: Kate Selway)

Kate Selway is in a helicopter on Christmas Day, roaring over a vast expanse of snow-covered moving ice.

Beneath her, the Denman Glacier stretches across the Antarctic horizon as far as the eye can see.

Riddled with crevasses — giant gaping cracks in the ice — it is spectacular, wild and treacherous.

"It's really stunning," she recalls. "You can see ice is flowing and cracking as it does."

She had been looking forward to seeing this view since she arrived earlier in December, after two years of hard work and planning to get to one of the most remote places on Earth.

Kate Selway in fur hat
This is Kate's third trip to Antarctica.(Supplied: Kate Selway)

Even though she's been to Antarctica twice before, this is her first glimpse of the glacier from the air.

And this is no ordinary joyride. It's part of a project to discover what lies beneath, and how this mass of ice might behave in a warming world.

Glacier melting faster than expected

The Denman Glacier spans an area 16 kilometres wide and 110km long in East Antarctica, around 5,000km to the south of Australia.

The glacier was first traversed by Sir Douglas Mawson and his team in 1912.

"It was so tough … doing this work with early equipment, bad clothing and no helicopters," says Dr Selway, an earth scientist with the University of Tasmania.

Today, it's melting before our eyes — faster than scientists expected.

Satellite view of Denman Glacier
A satellite view of the Denman Glacier taken in November 2022, with an inset map showing its location in East Antarctica.(Supplied: European Union Copernicus Sentinel-1)

Underneath the glacier lies what scientists think may be the deepest canyon on Earth, plunging around 3.5km below sea level.

And the valley may contain so much ice that if it melts, it could raise sea levels by 1.5 metres.

But while satellites and modelling have given researchers these tantalising clues, this helicopter journey is the first step towards setting foot on the glacier to see what's really going on.

"Our big question is how deep the trough of the glacier is," says Dr Selway, who studies how fast ice sheets are melting.

Before she arrived in Antarctica, Dr Selway planned on exploring five sites.

But where she sets foot isn't entirely up to her.

Crevasse
A crevasse that is about 50 metres wide. A snow bridge is still covering some of it while the rest has fallen away.(Supplied: Kate Selway)

This pristine environment is also perilous. If she unknowingly wanders onto a bridge of snow across a crevasse, it could collapse, sending her plummeting.

So her fate lies with mountaineers who must head out onto the glacier, secured with ropes, to check the sites are actually safe.

After making her first flight, she returns via helicopter to base camp at Bunger Hills — a bunch of dome-shaped tents on a rocky bit of ice-free land, 45 minutes away — to await their verdict.

Life in the deep field

Base camp is home to 27 scientists from a number of universities studying the glacier, and a host of support staff.

This is what's called "deep field" research. The nearest permanent research outpost, Casey Station, is 400km away.

The camp is in an area known as Bunger Hills.(Supplied: Kate Selway)

"Whatever happens back at home, you're not going to be able to get back," Dr Selway says.

But when she's there she switches into what she calls "Antarctic mode".

"I'm immediately in an alternate universe that is all encompassing."

Everything here gets flown in, including fibreglass domes used for medical and communication centres, yellow pyramid tents to house the camp toilets, and yellow dome tents for sleeping.

Toilet tent at Antarctic camp
The camp must limit its footprint and all solid waste is taken to Casey Station for processing.(Supplied: Kate Selway)

It's high-tech but still basic, and the droning hum of the generator can be heard from 6am to 8pm every day.

Temperatures usually hover around freezing and there's no heating in Dr Selway's modest hiking tent, so she must sleep in thermals, woolly socks, and a beanie.

The blackout lining in the tent gives respite against the ever-present sunlight.

"I haven't seen the Sun go down at all," she says.

The 24-hour daylight makes it hard to keep track of time and plays havoc with her body clock.

"Sometimes you have to force yourself to stop working and go to bed because your body still thinks it's the middle of the day."

Night time sun in Antarctica
In the Antarctica summer, sunlight is an ever-present feature, even late at night.(Supplied: Kate Selway)

As she chats to me via a voice messaging app, the internet signal pinging from a satellite, a helicopter thunders overhead.

This one isn't ferrying people, but is emptying waste from the camp toilets.

The scientists must protect Antarctica's special ecosystem from non-native microbes, pathogens, and contaminants.

"You can't just pee on the rocks," Dr Selway says.

"It's all got to be dealt with properly for environmental reasons. Quite a big part of life here is dealing with human waste."

Battling ferocious winds

After waiting two days, Dr Selway is cleared by the mountaineers to head out to the glacier to install her equipment, as long as she follows their strict instructions.

Despite only walking around 50m to put her equipment on the snow, she must stay on the exact paths set out by the mountaineers.

Avoiding crevasses is just one the challenge. Battling unpredictable and extreme weather is another.

A storm at the Bunger Hills camp.(Supplied: Kate Selway)

Out on the glacier, it's minus 20 degrees Celsius.

To stay warm, Dr Selway is cocooned in a big, thick suit she's made herself. At 152 centimetres tall, she finds it hard to get any off the shelf that fit properly.

At times, even standing up is difficult. Ferocious winds rip across the glacier surface and pummel her slight frame.

"As a small person, as soon as the wind gets to 30 or 40 knots, it's hard to keep upright."

As well as two balaclavas, ski goggles, and beanies to protect her from frostbite, Dr Selway wears two pairs of gloves which make plugging things in difficult.

Kate Selway working in glacial wind
It's a struggle handling equipment in the blowing snow.(Supplied: Constanza Manassero)

And it can be hard to see what's going on when driving snow blows over her face and equipment.

Dr Selway studies the huge ice mass using instruments that measure electromagnetic fields from the Earth to detect if the base of the glacier is melting.

"If [the glacier's] got a lot of meltwater at the base, then it can flow really fast. If it's really frozen at the base, then it's not going to flow and collapse as easily," she says.

Her work forms just one part of the larger Denman Terrestrial Campaign project studying the glacier.

Other scientists on the team measure the thickness and depth of the glacier using gravity, or sound waves, like those from "ice quakes" in the moving glacier.

And others collect ice cores, geology, and soil samples to study past climates and the glacier's history.

The winds are generally strongest in the morning.(Supplied: Mike Battersby)
Researchers drilling in a lake
Researchers drilling in a lake formed between an ice shelf and land. Samples can help reconstruct the past behaviour of the ice sheet and glacier.(Supplied: James Newlands)

While the team's on the ice, the helicopter pilot keeps an eye on the conditions.

If the weather turns bad or the winds pick up, safely flying back to camp becomes much harder.

Even when it's just overcast, the Antarctic landscape blends into the sky, so if the horizon threatens to disappear, pilots try and get people back to camp early.

Kate Selway with colleagues sheltering on a glacier in a 'survival' bag
Kate and colleagues Tobias Staal and Gemma Woldendorp sheltering in a bothy (survival) bag on the Denman Glacier waiting for the helicopter to return.(Supplied: Constanza Manassero)

"Getting stuck out there is the last thing you want," Dr Selway says.

"So, whenever we go anywhere up on the ice, we take stuff to be able survive for a week up there — tents, dehydrated food, and stoves."

On one of her later trips out to the glacier, Dr Selway got stuck with a group of colleagues for an hour in nasty weather while a helicopter went back to camp to refuel.

To keep warm, they sat in a circle in an emergency shelter.

"It was really cold and windy so all of us huddled together and drank hot chocolate until [the helicopter] came back."

Christmas on ice

By the time Dr Selway lands in Hobart on February 5, she'll have been in Antarctica for more than two months.

And she's ready to come home.

"I'm kind of sick of being cold all the time. And I'm really looking forward to flushing a toilet, and I'm really looking forward to eating some fresh food."

But she will also return with fond memories of the friendships she's made in this remote and pristine land.

Because the forecast for Christmas Day looked perfect for flying over the glacier, the team decided to gather for a celebratory lunch on Christmas Eve instead.

A bunch of people laughing and wearing Christmas hats
Kate loves the team she works with.(Supplied: Jacqueline Halpin)
Chief Scientist David Souter and camp chef Jacqui Hsieh in the kitchen tent on Christmas day
Chief Scientist David Souter (left) and chef Jacqui Hsieh (right) in the kitchen tent on Christmas Eve.(Supplied: Jacqueline Halpin)

But, thanks to bad weather, the cook's carefully planned meal for the occasion got stuck at Casey Station, so they ate an improvised replacement feast of cheese, prawns, and pastries.

"There are incredible communities of people in places like this … lots of scientists, and lots of people supporting us," Dr Selway says.

"You're down here for two months but make lifelong friends with all of these people."

Kate Selway with sketch of camp in Christmas gear
Kate with a sketch of the camp by biologist colleague Laura Phillips.(Supplied: James Newlands)
A hard dome structure with a kitchen inside
Inside one of the hard dome "melons" at camp containing a back-up kitchen, which Kate says is also a lovely place for a quiet cup of tea.(Supplied: Kate Selway)

Worth the challenges

Just days before she must leave camp, Dr Selway collects her final instrument — and its precious data — from the Denman Glacier.

And not a moment too soon. It's been a nail-biting time.

There's been a lot of bad weather lately, which gave her no choice but to sit tight and hope the skies would clear enough so she could grab the instrument before heading home.

Otherwise she would have to leave it on the glacier, and hope someone else retrieved it before winter set in.

Whatever the challenges, though, she says it's all been worth it.

"It really feels like an extraordinary privilege to be here.

"The landscapes are so stunning and otherworldly and things that most people just never get to see."

Ice Sheet Cliffs
Where the East Antarctic Ice Sheet meets the ice-free Bunger Hills you can see these impressive ice cliffs.(Supplied: James Newlands)

Dr Selway has seen the wonders of the icy north too. She's been to the Arctic five times, where she witnessed the melting of the Greenland ice sheet.

"Climate change is such a massive global challenge, and I feel like my skills of being able to do the science is how I can contribute.

"As I go on in my career, it's the science that keeps me coming back."

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