It's the coldest, driest, windiest place on Earth – and when it comes to understanding what kind of future our descendants could face, Antarctica may also be the most important place on earth. Science reporter Jamie Morton spent two days in the McMurdo Dry Valleys.

It's just gone 10.30am when I step out of a helicopter and into another planet.

The Dry Valleys and all that's in them – gargantuan glaciers, gravelly basins, flattened ranges and a lack of anything visibly green or growing – appear more like Mars than like McMurdo Sound, where we'd just flown in from.

The short hop from Scott Base had been almost entirely over ice and snow, then we'd swooped into this unearthly enclave called the Taylor Valley.

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It's strange to think you can have an ice-free ecosystem amid the endless white of Antarctica's polar wilderness.

You can reach for resemblances – maybe the South Island's Mackenzie Basin, or Mt Tongariro's Red Crater – but little here is comparable to anywhere you've been on Earth.

It's all so very big – and so deceivingly cold.

Heatwaves can be seen rising as moisture is sucked from the soil, but the air is so bitterly biting that briefly pulling off my gloves to take a picture sends a sharp sting to the fingertips.

The summer temperature typically hovers just south of zero - a balmy afternoon at the beach by Antarctic standards – but it's the browns and reds and greys of the landscape that can make the chill unexpected.

Captain Robert Falcon Scott's first impression of this barren desert was of a "valley of death" but the great explorer probably never saw conditions here rage as violently as they do.

The valleys act as perfect funnels for ferocious "katabatic" winds that can reach speeds of 320km/h and form when cold, dry, dense air is dragged downhill by the force of gravity.

Antarctica's McMurdo Dry Valleys are some of the most extreme places on Earth. Photo / Jamie Morton
Antarctica's McMurdo Dry Valleys are some of the most extreme places on Earth. Photo / Jamie Morton

Because the winds heat up as they descend, any water, ice and snow in their path is evaporated.

Over the winter, the mercury drops as low as -60C; over summer, the valleys are blasted by damaging UVA and UVB radiation.

And in between the seasons, temperatures can swing by 20C in just a day, driving rapid-fire cycles of freezing and thawing that make most life impossible.

You'll find few places anywhere on Earth as extreme as this.

Today, though, it's resplendent; the sky is a brilliant blue and the panorama is all too much to take in.

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The helicopter takes off, sending puffs of scree against the little cluster of yellow tents that hug our hillside.

As I watch it fade to a speck against the mountainside I find scale is about as foreign here as a beach towel.

I judge the Hughes Glacier, just above our camp, to be a 15-minute walk away, yet you can trudge toward it for the best part of an hour and it gets no closer.

Dwarfing that is the monstrous Taylor Glacier, flowing from the plateau of Victoria Land and into the western end of the valley.

Out of its tongue courses a ghastly dark red plume of iron oxide-tainted saltwater, appropriately named Blood Falls, which eventually reaches Lake Bonney, fanning out 7km across the valley floor.

Bonney's surface is permanently covered with a 4m-thick layer of ice and walking on it can be an arduous strain on the ankles.

It feels like someone has draped a white tablecloth over a clay track pocked with deep ruts and cracks; ice crunches beneath your heavy boots, sometimes tinkling and breaking like thin glass.

Nearby, a crumpled brown heap marks the remains of a wayward Weddell seal, whose carcass – teeth, whiskers, skin and bone - has been mummified for thousands of years.

It highlights, and rather grotesquely, an environment frozen in time.

Scientists know this and cherish it as one of the most geologically exotic places in the world.

Antarctica's McMurdo Dry Valleys are used as an analogue for the Martian environment. Photo / Jamie Morton
Antarctica's McMurdo Dry Valleys are used as an analogue for the Martian environment. Photo / Jamie Morton

An extraordinary amount of natural history is all here, neatly layered in the valley rim like a museum display case.

Some of the earliest rock is 600 million years old.

There are dark dolerite sills: a tell-tale sign of a massive volcanic system which, some 180 million years ago, produced eruptions titanic enough to tear the famous super-continent Gondwana apart.

If we fast-forward to 65 million years ago – around the time in Earth's history when dinosaurs met their apocalypse – we come to the birth of the dramatic 3500km mountain range that divides east and west Antarctica today.

Professor Tim Stern has long been in awe of these Transantarctic Mountains, and the ancient secrets they hold.

It so happens these valleys are the best places to unlock them.

Stern first came here as a fresh-faced 21-year-old, and he's returned more than four decades later as world-renowned Victoria University geophysicist.

Students Sam Treweek and Steven Kesler are here with him for a state-of-the-art gravity survey.

Each morning they climb out of their tents, pull on their boots, calibrate their GPS for 30 minutes and head out into the cold wind.

They take turns at lugging a 5kg gravity meter, which they fix into the ground every few hundred metres to record measurements in 15-minute bursts.

Victoria University student Sam Treweek takes readings on a gravity meter. Photo / Jamie Morton
Victoria University student Sam Treweek takes readings on a gravity meter. Photo / Jamie Morton

Their days are long: they're up as the sun rises over the mountains and, 20km of tramping later, they're back at camp by 8pm to cook dinner on a portable gas stove.

By the time I meet the team at the frozen shores of Lake Bonney, they've been at this for weeks and have covered most of their 60km survey area.

They're worn out and craving showers, proper beds - even Milo or a box of Vita-Wheats - but they're cheerful.

They laugh and joke and talk about life back home in Wellington.

"I mean, I could be home at the beach – this is effectively my Christmas holiday, because I'm right back into teaching as soon as I get back – but I love the environment here," Stern tells me.

"I really think the Transantarctic Mountains are one of the most magnificent places on Earth."

Like all Kiwi scientists working down on the ice, the work they're doing will make a critical contribution to global models that we use to observe our fast-changing world.

Their study all comes back to the rock properties and what's happening at the divide between the ancient continent that underlies much of East Antarctica and the far younger earth movements of West Antarctica.

Gravity readings help them calculate the density of mantle rocks at the boundary, which they're essentially trying to pinpoint.

"What's important from our point of view is to understand where this mantle extends, and how far it extends under the mountains," he says.

"And as we've been out walking in the Taylor Valley, we've seen active volcanism within two to three million years, which is a sure indication that the hot mantle is right under it."

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In the context of climate change, the work couldn't be more important.

That's because of something called post-glacial rebound: studies of the last Ice Age show how, as huge ice sheets melted, the outer part of the earth lifted as the weight was off-loaded.

"Global sea level change anywhere on earth is one of the first signals of post-glacial rebound," Stern says.

"So if you want to understand sea level changing – or how much of that is due to human influence versus natural background – you first have to unravel this process."

Antarctica's vast ice sheets store an equivalent 60m of potential sea level rise, yet we still don't know all that we should about how it will respond to a warming world.

Antarctica's Taylor Valley is ringed by enormous glaciers. Photo / Jamie Morton
Antarctica's Taylor Valley is ringed by enormous glaciers. Photo / Jamie Morton

But with every new study, the picture grows grimmer.

Just this month, a major paper co-authored by New Zealand researchers found changes in the tilt of the planet's axis could amplify the effects of climate change's impact on the Antarctic Ice Sheet.

Another recent study indicated that Antarctica's tipping point could be crossed somewhere near another 1C of global warming.

That threshold happens to be the line that nearly 200 nations, including ours, have drawn in the sand when signing up to the Paris Agreement to limit climate change.

Scientists are attacking the Antarctica puzzle from every angle they can: investigating small glaciers to enormous ice shelves, or microbes to minke whales.

Stern says he's fortunate their fieldwork is within short range of Scott Base.

Other scientists are toiling in places so desolate and naturally hostile we couldn't begin to comprehend the conditions.

Take the Siple Coast, a hot-spot for environmental sensitivity some 850km from Scott Base, where the West Antarctic Ice Sheet lifts off the seabed.

The sea ice floats near Antarctica's McMurdo Sound, as Mt Erebus looms in the background. Photo / Jamie Morton
The sea ice floats near Antarctica's McMurdo Sound, as Mt Erebus looms in the background. Photo / Jamie Morton

Even aircraft couldn't reach it, so a New Zealand team forged an 1100km path across the crevasse-covered Ross Ice Shelf, sometimes in total white-out conditions.

Or Cape Adare, a remote peninsula where a full-scale polar blizzard kept Kiwis huddled inside a tent for 35 straight hours.

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Back at Lake Bonney, Professor Ian Hawes is going to his own brave lengths.

He's sitting on the rim of a hole melted four metres through the surface, as his US collaborators make final checks on his cold water wetsuit.

Hawes is a softly-spoken Waikato University ecologist whose experience in Antarctica also spans back to the time he was 21.

Waikato University ecologist Professor Ian Hawes at Antarctica's Lake Bonney. Photo / Jamie Morton
Waikato University ecologist Professor Ian Hawes at Antarctica's Lake Bonney. Photo / Jamie Morton

He'd trudged from one side of the lake to other to greet me; now he's about to drop into water so cold that exposure to it would quickly bring death.

Even in their protective gear, divers can only stay beneath the ice for 45 minutes; when their fingers began to go numb, it is time to head up.

We're standing at the surface, a few metres from a heated little mobile hut where the divers try to warm themselves back up. Hawes checks in from below via radio every few minutes.

Final checks are made of Professor Ian Hawes' dive gear before he descends into Lake Bonney in the Dry Valleys. Photo / Jamie Morton
Final checks are made of Professor Ian Hawes' dive gear before he descends into Lake Bonney in the Dry Valleys. Photo / Jamie Morton

"How the temperature affects the dive gear is probably the main thing we worry about," he later tells me.

"Every night, we have to dry out all the gear and make sure there's no water left inside the regulators, which are ones we know won't freeze up in the cold water."

So what's it like down there?

Hawes describes it as a different world.

Professor Ian Hawes prepares to dive into the icy water of Antarctica's Lake Bonney. Photo / Jamie Morton
Professor Ian Hawes prepares to dive into the icy water of Antarctica's Lake Bonney. Photo / Jamie Morton

"If you look all around in the Taylor Valley, all you see is a moonscape: just dry soils, rocks and chunks of ice," he says.

"But as soon as you get underwater and get to the bottom of the lake, it's like a being in a tropical forest… it's completely covered in life."

That life has been slowly shifting.

Records stetching back to the early 1900s, when Scott's expedition measured the width of the lake, show the water level has been rising, dramatically so over recent decades.

The reason why is simple: more water is entering the lake from the melting of surrounding glaciers than is being evaporated by the sun.

What Hawes and his team want to know is what this means for the mostly microbial organisms living on the floor of the lake itself.

As the water grows deeper, they're receiving less sunlight and less energy, and entire ecosystem processes and functions are forced to change.

Professor Ian Hawes and his team had to melt a hole through the four-metre frozen surface of Antarctica's Lake Bonney. Photo / Jamie Morton
Professor Ian Hawes and his team had to melt a hole through the four-metre frozen surface of Antarctica's Lake Bonney. Photo / Jamie Morton

"We've been diving along a transect in the lake and collecting samples, from photosynthetic organisms, all the way up to nematodes and the highest forms of life."

Because they know the rate at which the lake is rising, the samples they've collected at set depths can be matched up to specific time periods.

Their study forms part of a wider, long-term ecological monitoring programme in the valleys, where other sites have lost entire communities of life that was found nowhere else.

"In the bigger scheme of things, we are looking at the extent at which we're losing and gaining organisms," Hawes says.

"And to step back even further, we're looking at the longer cycles involved – and the ability of these organisms to be resilient to the type of environmental change we're seeing today."

Because we can't see microbial organisms like bacteria, it's easy to forget that they're here in this apparently lifeless valley.

Scientists diving below Antarctica's Lake Bonney can only stay below the surface for 45 minutes at the most. Photo / Jamie Morton
Scientists diving below Antarctica's Lake Bonney can only stay below the surface for 45 minutes at the most. Photo / Jamie Morton

It's also easy to forget what the micro-world can tell us about the one we know, and how climate change is beginning to transform it.

Scientists have discovered a surprising amount of microbial diversity here.

Quite literally, they've barely even scratched the surface.

One Kiwi scientist has begun investigating how some these hardy bugs repair their own damaged DNA, pointing the way to new technologies we can all benefit from.

"One of my particular interests is the way we can use communities that have developed in these lakes to understand how a microbial world works," Hawes says.

"And if you think of the Earth's history, for almost all of it, it's been a microbial world – anything more advanced than bacteria and microbes is relatively more recent.

"So, when we dive down in these lakes, what we're essentially doing is going back millions of years in Earth's history, to a time when there were only microbes here.

"What this lake offers us is a rare window to a time period that is no longer accessible to us, except from fossils.

"And we can use the information to get new insights into how life works in its most basic form."

Even after all his years in Antarctica, Hawes remains just as enamoured by this place as Stern.

"I don't think you could ever get over how spectacular that landscape is when you get out of the tent first thing in the morning," he says.

"You can't ever lose the fascination of working here, and always finding something different that no one has ever seen before."

I later find my own Mars-on-Earth impression of the valleys wasn't far off the mark.

Many researchers who study them do so with one eye toward understanding their geomorphology and bacterial life - and another on the range of potential surface processes and organisms that might be found on the red planet, now and in the future.

In a way, that's possible only on the coldest, driest, windiest continent on the globe, I really had stepped out of that helicopter and into a new world.

Whether it stays this way remains up to all of us, and now.

Jamie Morton was hosted on the ice by Antarctica New Zealand.