Home science Secrets of the ice: unlocking a melting time capsule

Secrets of the ice: unlocking a melting time capsule

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Back in August 2018, archaeologists William Taylor and Nick Jarman were scrambling around a snowy, scree-strewn slope in the Altai mountains in northwest Mongolia at the end of an exhausting day. A few hundred metres above Jarman, Taylor and his colleagues were surveying the site, a disappearing ice field that local reindeer herders said had not melted in living memory. Now, each summer, it disappears almost completely.

Taylor looked down the mountain and saw his methodical colleague dancing and hollering, hopping from rock to rock. Thinking he was injured, Taylor headed down the mountain.

“Every time people hear you’re an archaeologist, they want to know the best thing you’ve ever found,” says Jarman, who like his colleague is an assistant professor and curator of archaeology at the University of Colorado Museum of Natural History. “I knew what I had found rewrote all those anecdotes.”

There, in crumbling snow, was a perfectly preserved arrow shaft. It was delicately decorated with ochre markings, its carving and features completely protected by the ice even though it was 3,000 years old. Normally, organic items such as this are destroyed by exposure. Jarman instantly found a piece of another arrow shaft. “You can feel when you’re in a hotspot – where everything has come together to allow stuff to be preserved,” he says.

Deep freeze: archaeologists search for Viking relics at Lendbreen, Norway.
Deep freeze: archaeologists search for Viking relics at Lendbreen, Norway. Photograph: Secrets of the ice

Convinced he would find the arrowhead nearby, Jarman quickly swung his metal detector over the snow. It beeped. “I brushed back 2in of snow and I saw this copper-coloured point. It resolved itself into a bronze arrowhead. It had little scraps of animal sinew still tied around it. It had somehow worked itself free from the shaft, and had just dropped off right there. I yelled and just started laughing and jumping about,” he says. The arrow and its shaft had lain undisturbed, packed deep in the ice since the Bronze Age, more than 3,000 years ago, when it was lost, dropped or shot. It is a totemic thing to see; it shivers with a swift, elegant menace.

“The feeling that I get when I find these supremely well-preserved organic objects, is that I am the first person to encounter this since the original user,” says Jarman. “You feel this connection in time between the last person to use it and yourself.”

The scientists were exploring a previously perennial ice patch at 4,000m in Mengebulag in Mongolia’s Khovsgol province. They were told about the site by a local guide, Bekbolat Bugibay, who showed them another arrow he had found there that he claimed dated from the time of Genghis Khan. “His guidance was indispensable,” says Taylor.

For generations, nomadic reindeer herders had used this munkh mus or “eternal ice” in summer months to cool their herds and offer them respite from the biting insects that plague these heights. And before written or oral history – before humans had domesticated animals – nomadic Mongolians had observed the reindeers’ behaviour, and had lain in wait, ready to hunt.

But in the summers of 2016 to 2018, ice patches in Mengebulag melted for the first time in living memory. Summer temperatures in Mongolia have increased 1.5C in the past 20 years – higher than the global average. And as the great thaw opened a window into a once inaccessible past, the archaeologists were overwhelmed by the sheer volume of material revealed: horsehair ropes, countless shafts, spears, the sinew of animals used for tying arrowheads and making bows, all intact, but all under imminent threat of destruction now that they were free of the ice.

This is a story playing out worldwide as global heating gathers pace, creating a new academic discipline – “glacial archaeology”. This, though, is something of a misnomer, says Professor Brit Solli, an archaeologist at Oslo University, Norway. “Most of the finds emerging from melting ice caused by climate change are not from moving glaciers, which tend to crush and destroy objects, but from large ice patches, which ebb and flow,” she says. That said, some ice patches contain snow that fell over 10,000 years ago, meaning they also offer climate data in the same way as glacial ice cores.

Back in time: a snowshoe for a horse, as yet undated, but the artefacts it was found with are from the Iron Age, around AD300.
Back in time: a snowshoe for a horse, as yet undated, but the artefacts it was found with are from the Iron Age, around AD300. Photograph: Espen Finstad/Secrets of the Ice
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In 1997, Kristin Benedek and her husband, biologist Gerry Kuzyk, were hunting wild sheep in the mountains of the southern Yukon, Canada, when they found a pile of caribou dung that had emerged from a melting ice patch. Sticking out of the pile was an ancient hunting weapon with sinew and feather fletching still attached. The spear, or throwing dart, was analysed and found to be 4,300 years old.

This launched the Yukon Ice Patch Project, which partners six First Nations tribes in whose territory the ice fields are located. It marked the beginning of ice-patch archaeology as an active field of study in North America. There are now thousands of similar sites in the northern hemisphere, from the Yukon through the US, to the Italian Alps, Mongolia, Siberia and Norway – which alone is home to over 50 sites.

The field of glacial archaeology is growing quickly as scientists race to preserve the past before exposure to the elements destroys them forever.

“There is an urgent imperative to do more of this work and to mitigate the loss to cultural and scientific heritage that is occurring as we speak,” says Taylor.

The most common experience among scientists is to arrive and feel they were too late. “It’s ‘rescue archaeology’,” says Jarman. “We’re salvaging stuff that, if we’re not there to document it and collect it, is going to be gone in a year or two.”

The archaeological record and carbon dating of artefacts taken from the ice of Norwegian high mountains reveals how humans adapted to climate change in the past, says Solli. “There is evidence of increased mountain activity in the period known as the Late Antique Little Ice Age [536-660 AD]. When crops failed following tremendous volcanic explosions, people abandoned their farms to hunt for their food instead,” she says.

“It’s an interesting twist that climate change is providing us with some important clues to the long-term trajectory of the relationship between people and climates,” says Taylor.

‘We are salvaging stuff that’s going to be gone in a year or two’: a wooden bit for goat kids and lambs to prevent them suckling their mother, as the milk was processed for human consumption.
‘We are salvaging stuff that’s going to be gone in a year or two’: a wooden bit for goat kids and lambs to prevent them suckling their mother, as the milk was processed for human consumption. Photograph: Espen FInstad/Secrets of the Ice

Dr Shane Doyle, a Crow Indian who now lives in Bozeman, Montana, has acted as consultant on several ice-patch sites, collaborating with archaeologist Craig M Lee of the University of Colorado at Boulder. “It’s so amazing that we can just scrape a few feet down and all of a sudden we’re 10,000 years into the past,” says Doyle. “And it’s also frightening that the ice is melting at such a rapid pace. We have to get these items as soon as possible, because they’re not going to last another year.”

Some objects to have emerged from the ice are so old they could not be dated by standard radio carbon dating techniques. The oldest intact wooden object ever to have been recovered from an ice patch melted out in the greater Yellowstone ecosystem. In 2007, Lee uncovered a birch shaft, believed once to have been launched by a spear-throwing device called an atlatl, that was found to be around 10,300 years old. “I was gobsmacked to see this ancient spear shaft just lying in the runoff channel at the edge of the ice,” he says.

Lee is deliberately vague about the exact location. “Unfortunately in the US, unlike Europe, there’s a difference in people’s relationship to ancient materials – and particularly Native American culture. There’s still a colonial mindset here. Many people don’t realise that there’s really a robust living Native American culture – they want to collect things that relate to a bygone era, but they don’t realise they can still engage with living native people – you don’t just have to romanticise their existence in the distant past.”

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Another standout artefact recovered by Lee’s team was a piece of complex and complete basketwork, probably used for sorting and milling seeds from whitebark pine trees. The wide, shallow bowl was identified in 2013 at the remains of an ancient ice patch whose whereabouts is also protected. Conserved and analysed at Mercyhurst University, Pennsylvania, the rods and coils of the artefact, from around 600AD, are made of willow. It provided a more complex and complete picture of pre-Columbian societies than the standard, predominantly male, hunting-related artefacts, says Lee.

“It’s not to say that women did not hunt,” he says, “but one of the things that you tend to see in indigenous cultures is that the people who make baskets are almost exclusively women. It has been really cool to see something that is almost definitively associated with the hands of women. These locations have resources that would be amenable to use by groups, so not just hunters, but also family.”

Under wraps: parts of the Rhone glacier are covered in blankets above Gletsch near the Furkapass to prevent it from melting so quickly.
Under wraps: parts of the Rhone glacier are covered in blankets above Gletsch near the Furkapass to prevent it from melting so quickly. Photograph: Urs Flueeler/EPA

Doyle says that, from a Native American perspective, it was no surprise to find evidence of community living and gender cooperation in these areas. “We have always known that women and men are equal in so many different ways, and that wherever men went, women went,” he says. “There were families up there – men, women and children. We didn’t differentiate between where genders could go like other cultures did. It was a beautiful thing to see that proven.”

Glacial archaeological work also dismantles the flawed and archetypal view of these environments as “wildernesses”, says Lee. “They are incomplete ecosystems without the humans that once lived, worked, hunted and lived here,” he says. “The wider culture has underestimated where native people went,” agrees Doyle. “My people didn’t just visit… They were there all the time, and they’ve left the remnants of that.”

The icy mountains of Norway have proven rich, latterday hunting grounds for glacial archaeologists and it was here in 2011 that some of the most important finds were made. Solli points out that until scientists began to find these objects and document indigenous use of the mountains in antiquity, many Norwegians knew little about this part of their own history.

Solli’s colleague, Professor Marianne Vedeler, wrote in the journal Antiquity about a sensational 2011 find: an ancient tunic, miraculously intact, found in Lendbreen, a medieval Viking mountain pass. That year, archaeologists were working on the Lendbreen glacier in Oppland County, when they found what appeared to be a crumpled up piece of fabric. The tunic was woven from sheep wool in a diamond twill design between AD230 and 390 and had been well worn, repaired and patched. Only a handful of garments from this period have ever been found in Europe. With a simple cut – it was pulled over the head like a jumper – it was probably worn by a slender man around 5ft 6in tall, Vedeler reported.

Bronze Age leather shoes from 1,300BC and a ski with strapping from 700AD have also melted free in Norway in recent years. Last year, snowshoes for horses and other items relating to the hunting and domestication of animals were uncovered in the same area.

Melting point: cracks in the ice are a result of climate change.
Melting point: cracks in the ice are a result of climate change. Photograph: Alexandre Meneghini/Reuters

Lars Pilo is Europe’s glacial archaeological figurehead, with 15 years’ experience in the field. He points out that, remarkably, scientists in both Mongolia and Norway have discovered that identical, yet innovative hunting methods were used.

Wooden poles known as “scarer sticks” have been found on and around these ice patches where reindeer once flocked. The poles were used to corral the herds into position for hunters, says Pilo. The poles, topped with flags, were planted into the ice and used to alarm the animals, who instinctively fear any sign of motion on the featureless landscapes. The flocks would head away from the fluttering flags, towards the waiting hunters.

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Pilo says he particularly enjoys finding objects with a human feel and connection to them, such as clothing. Once in 2011, he found a small arrow that seemed a little different from others he had encountered. “It turned out to be a child’s arrow, a child’s toy, which showed how central hunting was to these people,” he says.

Also in 2011, Pilo found a piece of wood, around 10cm long, at the Lendbreen site. He was convinced it was a needle and displayed it as such in an exhibition. An elderly visitor approached him and told him it was mislabelled. It was, she said, a small wooden bit, used to prevent young calves and goats from suckling their mothers. She had used the same equipment when she was a girl, on her father’s farm, recalling that tough juniper wood was always used for the job. “Ours turned out to be juniper, too, but it was radiocarbon dated to be from 1080,” Pilo says. “You see bits of pieces of human history that are melting out in a reverse time order. So we started with stuff from the Iron Age. Then came the Bronze Age – and now it’s the Stone Age. We’re melting back in time.”

But, for all the discoveries, the field of glacial archaeology is tainted with a bittersweet aftertaste. Scientists know the only reason they have such an endless bounty of astounding material cascading from melting ice patches is because of systemic climate collapse.

“There is a shadow hanging over all of this work, because the only reason you are able to do this is because the environment is so profoundly out of whack,” says Jarman. “It really pushes me to be the best archaeologist that I can be. It pushes me to hike that extra mile and to do the best job of recording these things that I can, because there is the real possibility that we may only get one chance at it.”

Pilo sees the future in bleak terms. “In our high mountains, 90% of the ice is going to melt away in this century. It’s going to go no matter what we do. That is really hard to comprehend, both rationally and emotionally,” he says.

It is hard, if not impossible, to remain optimistic about the fate of the Earth’s ice. In June, a northeastern Siberian town, Verkhoyansk, set the record for the highest temperature ever recorded in the Arctic Circle. Summer temperatures in the town, which lies 3,000 miles east of Moscow, hit 38C. In July, methane – one of the most damaging greenhouse gases – started leaking from beneath the seabed in Antarctica for the first time ever. We may have now passed a long-feared tipping point.

In a year when the unthink able has become the everyday, when profound changes to lifestyle, economy, travel, ambition and health have been forced upon billions of us by a tiny virus, at a time when science has trumped even the most bombastic rhetoric, it is surely important to stop and reflect on the environmental consequences of our prior economic model. We may soon look back on the Covid-19 pandemic as the good old days before climate change raced away from us.

Will we soon be swapping our smartphones for atlatl, those ingenious ancient spear-throwing devices? It’s too soon to say, but archaeologists have the luxury of a very long view.

“Technological advancement is not permanent. It can fluctuate back and forth,” says Jarman. “We’ve seen that happen throughout human history, and it would be hubris to think that it couldn’t happen again,” he says. “I hope that if it does, that is because we have intentionally managed a soft landing, choosing sustainable technology because we want to, and we know it’s the right thing to do, rather than being forced into it.”



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