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Nick Mott This season of Threshold is underwritten by the Pulitzer Center on Crisis Reporting.


Amy Martin I’m on the island of Grímsey, off the northern coast of Iceland, standing in front of a huge concrete ball. It’s nine feet in diameter, and it has a grey, pockmarked, sort of lunar- looking surface.

Amy Martin It’s, super strange, ...

Amy Martin Welcome to Threshold, I’m Amy Martin and this thing is called Orbis et Globus – that’s Latin for circle and sphere – and it’s been placed here to mark the Arctic Circle. Grímsey is a tiny island – five square kilometers, or two square miles – and it’s home to less than 100 people. On the day I was there, it was also home to thousands of nervous puffins, a couple of stoic sheep, and about a dozen horses that looked like they’d been trained in picturesque-ness by the Icelandic tourism board. But once I left the village, I didn’t see any other human-made structures, until I came upon this thing. This enormous grey ball sitting in the grass at the end of this Arctic island. It’s wonderfully weird. It feels like I might have found a stone flung from the slingshot of a mythological Nordic giant.

Amy Martin I can’t wait to talk to the artist about it. I love it that it’s got this hole through it, so you can see through it.

I stepped up to look through the hole running through the middle of the ball, and I started to hear something. A low, droning sort of hum.


Amy Martin Oh my gosh, that’s what it sounds like? [LAUGHS]

Amy Martin I am standing on the Arctic Circle. And my voice sounds really strange right now because I am speaking into an enormous ball of concrete. [LAUGHS]

This is the sound of the Arctic Circle. On a windy spring night, at the end of Grímsey island, this lonely piece of art was singing to itself.

So far this season, we’ve focused our attention on two specific Arctic places. This time, we’re going to zoom way out, and try to answer two fundamental questions about the region as a whole. In the second half of the show, we’re going to try to figure out why humans ever came to live in the Arctic in the first place. But we’re going to start with something even more basic than that: what is the Arctic? Like, where exactly does it start and stop? And that’s where this giant singing ball of concrete comes in. It was designed to mark where the place where the Arctic officially begins. But there’s a plot twist here: we put this line on our maps and globes as a fixed, permanent thing, but this sculpture was designed to move.

Amy Martin Why is there a giant ball of concrete on the Arctic Circle? And why does this huge sculpture have to be moved every year in order to stay on the Arctic Circle?

Orbis et Globus, and so much-us more-us, on this episode of Threshold.


Amy Martin One of the most fascinating things about the Arctic is the way it scrambles our relationship with light. If you’re north of the Arctic Circle on the summer solstice, in June, the sun never sets. And on the winter solstice, in December, it doesn’t come up at all. This is why the Arctic Circle is where it is: it’s supposed to mark this spot where there’s 24 hours of light for at least one day each summer, and 24 hours of darkness one day each winter. All across the Arctic, there are signs marking this line: little spots where tourists to stop and get their pictures taken. Sometimes locals set up shops nearby, and sell souvenirs. And that’s the way it’s always been on Grímsey Island, too. Until these two guys got involved.

Steve Christer I’m Steve Christer, and I’m an architect.

Kristinn Hrafnsson And I’m Kristinn Hrafnsson, and I’m an artist.

Amy Martin How do you say your last name again?

Kristinn Hrafnsson Hrafnsson. Easy. Easy.

Amy Martin I met Kristinn and Steve in Reykjavík, Iceland’s capital, where they’ve collaborated on lots of public art projects over the years. In 2013, they heard about a competition to make a piece marking the Arctic Circle on the island of Grímsey. And as Kristinn studied the submission guidelines, he got really intrigued by one small detail about the project.

Kristinn Hrafnsson I stumbled across a small number, they said that the Arctic Circle is moving 14 centimeters a year, and I found this rather strange. So I thought let’s search this out.

Amy Martin Kristinn research led him to the third character in this story–

Thorsteinn Saemundsson My name is Thorsteinn Saemundsson.

Amy Martin Thorsteinn is an astronomer. He’s retired now, but he used to work at the University of Iceland.

Thorsteinn Saemundsson Actually, my specialty is the effect of the Sun on the Earth.

Amy Martin Thorsteinn told them it was true: the Arctic Circle isn’t fixed. It moves. It moves because the angle of the Earth’s axis moves. To understand this, it really helps to have a visual aid, so hold your hand up in front of your face, straight up and down, so you’re looking at the edge of your first finger. Now tip your hand forward just a little bit. That’s what the Earth’s axis looks like. The top of your fingers are in the Arctic, your wrist is in the Antarctic. But now, move your hand back up, just a touch, so it’s closer to straight up and down. Then push it forward again. That’s what the Earth is doing. That’s what we’re all doing. Riding on this planetary seesaw, up and down, between 22 and 24-and-a-half degrees. And this movement changes the amount of the planet that goes into total darkness on the winter solstice and total daylight on the summer solstice.

Picture a giant contact lens resting on top of the globe. The Arctic Circle is the edge of that lens. It spreads out as the Earth’s axis becomes more horizontal, and shrinks up when it gets more vertical. So we essentially have more Arctic when the axial tilt is greater: not necessarily more cold, just more surface area of the planet that experiences these extremes of light and dark. Thorstein says this movement of the Earth’s axis happens in a predictable, cyclical way.

Thorsteinn Saemundsson And this period is about 40,000 years; 20,000 years in one direction and 20,000 years back.

Amy Martin We’re currently somewhere in the middle of that spectrum, kind of splitting the difference between the most-tilted and least-tilted spots. But the axis is moving closer to straight up and down, so the Arctic Circle is moving north. And what this means for Iceland is that the circle is slowly slipping away from them. It used to run right through the mainland, but now, this small island off of the northern coast is the only habitable spot in the country touched by the Arctic Circle. And that’s drawn tourists here for decades, as Steve Christer describes.

Steve Christer You will have noticed when you arrived in the plane is there is this sign that’s made of aluminum. And that’s where they unload the tourists from the airplane, could walk them around the sign, give them a certificate and send them back home again.

Amy Martin In 2013, the local government decided this Arctic Circle marker was due for an upgrade. So, they launched a competition, and like Kristinn said earlier, the information they put out said that the Arctic Circle was moving 14 centimeters a year. But Thorsteinn figured out it was actually moving a lot more than that: an average of 14 meters a year. That’s the difference between five-and-a-half inches versus 46 feet. And at that rate, the Arctic Circle on the island of Grímsey for a few more decades.

Kristinn Hrafnsson It’s heading north, yeah. And it will leave the island in about 2047 I think you calculated?

Amy Martin After that, the Arctic Circle will continue its northern migration for thousands of years, leaving all of Iceland behind, until the Earth’s axis begins to tilt back in the other direction. This was not great news for the people of Grímsey. They’d always been told the Arctic Circle ran through the middle of their island, right next to the airport, and the souvenir shop.

Kristinn Hrafnsson But when we made, found this out, then we saw, this is not true.

Amy Martin Steve and Kristinn realized they had a decision to make. They could ignore the science of how the Arctic Circle actually works, and just make another stationary monument in the same place where it had always been. Or, they could take in this new information, and let it reshape their whole idea of what this monument was about. And as you’ve no doubt already guessed, they decided the complicated facts were much more interesting than the nice, easy fiction.

Kristinn Hrafnsson So everything is changing, everything’s on the move. So it’s a fantastic way of seeing this.

Amy Martin They started to dream up ideas for a moving monument.

Steve Christer We were thinking at one time that we could have a, just a, a band across the island, and we could get a horse to graze across the line. So we had lots of different ways of representing this moment. And then gradually it crystallized into something as simple as, as a ball because it’s something you can move. And it also represents what we’re on because everything that we’re talking about or thinking about is actually affected by balls, so it seems quite logical that the thing that is being affected at the end of the day is another sphere.

Amy Martin OK, so, some kind of ball. Something that can be rolled. But also, something that doesn’t move too much. Grímsey is a windy place.

Steve Christer It has to have a certain presence, a certain physicality, a certain weight.

Amy Martin So what did they end up with? An enormous ball of concrete.

Steve Christer The thing weighs eight tons.

Amy Martin It’s three meters in diameter, or about nine feet.

Steve Christer So it’s, it’s bigger than us. Yeah, that was the thing that we realized: it had to be big enough to be something that you couldn’t put your arms around. Even if five people link their arms, they’d be having trouble. So it’s something you can’t contain. It has its own life and does its own thing. And we just have to follow. Yeah, I’m like, now even though we know it’s going north, this summer it will go south.

Amy Martin Yup. You heard that right. The Arctic Circle isn’t only moving in one direction.

Thorsteinn Saemundsson The moon has an effect, too.

Amy Martin Thorsteinn says that as the Earth’s axis moves slowly back and forth on that 40,000-year see-saw pattern, there’s a much smaller, faster miniature see-saw happening as well. This wobble is caused by the moon.

Thorsteinn Saemundsson And this is called nutation and it is a period of about eighteen point six years.

Amy Martin That’s nutation with an N in case you want to look it up. What it comes down to is this: although the Arctic Circle is currently moving northward, that movement isn’t a straight line. It’s a squiggle: a big line moving in one direction, with a bunch of smaller little zig-zags contained within it. We’ve got pictures of it on our website which definitely helped me wrap my mind around this. And then, just when I thought I really understood what was going on, Thorsteinn said this–

Thorsteinn Saemundsson I must say, I must add that there’s one factor that comes into this, and people never think about that, or seldom think about that. And that is the movement of the Earth’s crust. This is something we can’t predict very accurately.

Amy Martin The Earth’s crust itself is moving. The surface of the planet, it’s made of moving parts. Every spot that we’re standing on was once in a different place, and will be in a different place again, later.

I have to say, as I was learning all this, my heart kind of went out to Steve and Kristinn, and the organizers of this competition. It seemed like a simple challenge: make a monument to the Arctic Circle. You know, just make something pretty or interesting to place on this tidy little line that human beings have drawn around the top of the Earth. But the deeper these two went into that project, the more complexity was revealed.

Steve Christer But I think that’s also something you accept. As you get older, you realize that you don’t have a grasp on everything. The older you get the more you realize you don’t know.

Amy Martin This kind of thing has happened to all of us: this moment when we find out some new information that makes everything so much harder and more complicated than we thought it was. And then we have to decide if we’re going to take that in, or turn away. This happens with climate change. As we learn about how our human activities are impacting the climate, it can get so overwhelming that we’ll twist ourselves into knots in the effort to avoid accepting reality.

And one of those knots is related to this movement of the Earth’s axis, that seesaw thing that we did with our hands before. Some people are spreading the idea that this change in axial tilt is one of several natural processes that are heating up the planet, not human actions. You may have heard this yourself and wondered, could there be anything to that? So, let’s just examine it quickly.

First of all, the Earth’s climate does, of course, change naturally. Historically, the planet has fluctuated between ice ages, and warmer periods, and changes in axial tilt are part of what drives that pattern. But those changes play out over huge timescales – tens or even hundreds of thousands of years. The warming we’re experiencing now is happening at lightning speed in comparison: it can be measured in decades, and centuries. And the cause of that warming is not a mystery. It’s us.

And this is a total drag. Like, it’d be so much easier if this wasn’t true, and we could blame global warming on the stars, or the aliens, or anything other than ourselves. But the reality is, burning fossil fuels moves carbon into the atmosphere, and that heats up the planet. This is not in doubt; it’;s a fact. So we have a choice. Do we accept the truth, as difficult as it might be, or do we try to push it aside, so that we don’t have to change? When it came to making this Arctic Circle monument, Steve and Kristinn chose option number one. They opened themselves up to wherever the more complicated truth might lead.


Amy Martin And it turned out to lead to something pretty darn cool.

Kristinn Hrafnsson This is a moving thing. It follows the circle, which is nothing you can touch or see. And that’s interesting, that the object is following this idea.

Steve Christer The ball is the least important thing about it. The piece itself is the movement.

Amy Martin We humans don’t really like change. We like to make sharp lines, and firm definitions, and once we get comfortable, we want to stay that way. But the actual, physical world doesn’t really work this way. It’s really hard to find a straight line in nature. Instead, there are curves and twists, blurred boundaries and overlapping branches. And always, always, change.

Kristinn Hrafnsson Everything moves. Everything. Nothing excluded.

Amy Martin Even the Arctic Circle. And an eight-ton ball of concrete, both of which are scheduled to leave Grímsey Island in the year 2047.

Steve Christer And that’s when Kristinn and I go up there with our Zimmer frames and kick it into the ocean.

Amy Martin What’s a Zimmer frame?

Steve Christer It’s a walker, a [INDISCERNIBLE]

Amy Martin OK, gotcha. [LAUGHS]


Amy Martin So the question we started with here is: what is the Arctic? The answer? Anything above a zig-zaggy line, which fluctuates between 65-and-a-half and 68 degrees north. Which is so messy and complicated. There’s really nothing about the Arctic that obeys our rules.

Thorsteinn Saemundsson We are very small in this universe. Much, much smaller and less significant than most people think.

Amy Martin We’ll have more after this short break.


Amy Martin Welcome back to Threshold, I’m Amy Martin, and we’re tackling two questions in this episode: what is the Arctic, and why did humans ever decide to live there? And the journey to answer to that second question begins tens of thousands of years ago–


–here. It’s summertime, and in a small Siberian village, next to a river, people are settling in for the night. The kids are exhausted after a long day of collecting berries and catching rabbits in the wilderness. The adults are taking advantage of the 24-hour Arctic light to do some fine hand work. One person etches a pattern into a cup made of bone – just a little design, to add some flair. Another is sewing a parka out of reindeer hide in preparation for the next winter. And when they finally put down their projects and snuggle in under their bison hides, their bellies are full.

Vladimir Pitulko Yeah, it was a good place. It was next to a river crossing.

Amy Martin This is Vladimir Pitulko. He’s an archaeologist with the Russian Academy of Sciences in Saint Petersburg, and in 2001, he was leading the team that discovered the remains of this ancient settlement, which was buried in the partially frozen soil way up in north-central Siberia, near the Yana River. The place is an archaeologist’s dream. They found drinking vessels and axes, plates and spears – and lots of indications that these people were excellent tailors.

Vladimir Pitulko In Yana, we have hundreds of needles. I think this is the biggest collection in the world which comes from a single site.

Amy Martin Before the Yana River discovery, archaeologists thought humans first came to live in the Arctic about 14,000 years ago, toward the end of the last Ice Age. So when the radiocarbon dates came back on these artifacts, Vladimir was stunned. They are 32,000 years old, proof that we’ve been living in the far north more than twice as long as anyone previously thought. And further tests have yielded even older dates.

Vladimir Pitulko It was really fun to know that it was that old. No one would expect that.

John Hoffecker It’s way up in the Arctic right, it’s up at 70 degrees latitude north.

Amy Martin This is paleoanthropologist John Hoffecker.

John Hoffecker And so one of the things that people had to deal with up there for the first time ever, right, was very low sunlight. The sun goes down in, what is it, in late November, whatever, it just and it stays down. It’s all dark. For months.

Amy Martin John is a fellow at the Institute of Arctic and Alpine Research at the University of Colorado in Boulder. He and Vladimir have collaborated for decades on research about early human migration into the Arctic.

John Hoffecker We’ve got stuff coming out of those sites that we don’t have for any other sites, right.

Amy Martin He says it’s hard to overstate the importance of the Yana River site.

John Hoffecker And a lot of this stuff is decorated, right? It’s fancy. It’s not just basic utilitarian stuff, it’s they, they really put some craft and art into this stuff. So we have, for instance, we have these decorated ivory dishes. I mean those are the oldest dishes and cups and things like that in the world.


Amy Martin So, how did the makers of these decorated dishes end up in far northern Siberia? Our species originated in Africa, and began migrating out of that continent at least two hundred thousand years ago, probably even before that. But those early homo sapiens didn’t go to the Arctic. They hung out across the Middle East, made their way to Indonesia and beyond, and even pushed north into central Asia. But once they hit a certain latitude, they stopped.

For tens of thousands of years, homo sapiens stayed south of the Arctic Circle. And then, around 70,000 years ago, a new wave of humans began to leave Africa. And John says this exodus was different than the ones that came before.

John Hoffecker It’s very rapid. It’s very successful. They are very quickly occupying all of these places that people were never able to live in before.

Amy Martin This later wave of humans were the people who went on to populate the globe. They were the ones who came to live at the Yana River site, and many other places across northern Eurasia. They walked east across Siberia until they bumped into a gigantic ice sheet and could go no further. When that ice melted, they quickly entered the Americas. We are all descendants of these adventurous explorers, who went to live in the far north, when no one else had done so before. So the question is, why? After a really long time of not going to the Arctic, why did humans suddenly decide to go live in Siberia?

John Hoffecker Well, that’s, OK, so, ...

Amy Martin John has a really interesting answer to this question. And it has to do with the number of rabbit skeletons Vladimir Pitulko’s team discovered.

Vladimir Pitulko They hunted them in a huge number, and in many cases they just did not eat them. Because you’d find the complete skeleton, so they took the fur and just...

Amy Martin He says it appears that the Yana River people often didn’t eat the rabbits – they were after the pelts, which they used to make long underwear. That must have felt quite soft and cozy, but Vladimir says they wouldn’t have lasted very long. After a few months of steady use, the fur would break down.

Vladimir Pitulko But it doesn’t matter, you have to change it anyway for sanitary purposes.

Amy Martin So maybe everybody needed two or three pairs of rabbit fur underwear each winter. And it takes a lot of rabbits to make one set of long johns. But, I was still puzzled: if they went to all the trouble to catch so many hares, why wouldn’t they also eat the meat? Weren’t they constantly fighting off starvation?

Vladimir Pitulko No, they had, they had lots of good animals for food, bison and horse and reindeer, so they did not care about eating the little hares which is actually not really tasty. I can eat it, but, not really like.

Amy Martin This shocked me. At least some of the time, these prehistoric Arctic Siberians had so much to eat that they could be picky; they could afford to have likes and dislikes.

John Hoffecker OK this isn’t just, like, these aren’t people who are barely clinging to existence right and making, you know, the basic essentials of life.

Amy Martin Certainly, life that far north was hard, but this shows that not every moment was devoted to basic survival.

John Hoffecker These sites look like they’re winter occupations, OK. You know, this doesn’t look like a, like a hunting camp that was occupied by a few people, you know, like in July, who then you know scampered down south again, you know, at the end of the summer or something. These look like houses.

Amy Martin John says it looks like the Yana River people may have used internal hearths, storage pits, all kinds of innovative stuff.

John Hoffecker To me, it seems like there’s a revolution in technology, which is, I think essential for occupying places like the Arctic. And we see it first in Africa, and then it’s like these folks are bringing it with them. And there’s another thing. They also needed some pretty complicated technology to deal with the extreme low winter temperatures. And so we, you know, we see indirect evidence for tailored, insulated clothing for the first time.

Amy Martin In the Arctic, sewing is just as much of a survival skill as hunting. That rabbit fur underwear Vladimir was describing? That was a life-saving innovation. And John believes all of these things together suggest a significant pivot point in the story of human evolution.

John Hoffecker My argument is that there’s a, there’s a change in cognitive faculties.


John Hoffecker I would argue, and at least a few of my colleagues would argue, that there’s evidence for some significant behavioral or cognitive differences.

Amy Martin John says the tools needed for catching rabbits and other small mammals are much more sophisticated than the big game weapons that had already been in use for millennia.

John Hoffecker You have to go through a whole series of logical steps that are computationally more complex than, you know, say, just you know, making a spear.

Amy Martin To be clear here: John is not saying this cognitive change was caused by living in the Arctic. He thinks people in Africa went through some kind of evolutionary change prior to that wave of migration around 70,000 years ago. Basically, he believes they were just a little bit smarter than the very first homo sapiens, who had left the continent much earlier. In his view, it was because of that increased brainpower, that this later wave of people were able to live in places no human had ever gone before. Places like the Yana River, and several other sites that have been discovered in far northern Eurasia. And when these early humans got there, they likely had this whole ecosystem to themselves – no primate competitors.


Amy Martin So, why did we first come to live in the Arctic?

John Hoffecker Because we could.


Amy Martin Because we could. And that may have made us unique.


Maybe the Arctic became the special niche of the most advanced humans ever to walk the Earth. Maybe, if John is right, an increase in intelligence allowed our ancestors to survive in places where earlier strains of homo sapiens just couldn’t make it. In short, maybe we couldn’t become Arctic until we became fully human.


Every human migration story is complex, and this one is no exception. Climate, competition and many other factors were also at play in our first forays into the north, and John says some of his colleagues think he might be overestimating the role of cognitive changes in this story. But there isn’t a debate about the most important point here, which is this–

John Hoffecker You can’t live in the Arctic unless you have some fairly sophisticated technology.

Amy Martin Technology for clothing, shelter, hunting a wider range of land animals.

John Hoffecker Or even better, and obviously, you know, the Inuit were masters here for exploiting a very rich food resources of the northern ocean, the whales, above all.


John Hoffecker And that’s, I mean, the thing is that the Inuit figured out this, this amazing trick of, you know, not only surviving in the Arctic but prospering, I mean building large, relatively stable communities. Villages. And it was to do something extraordinary that I don’t think that you know the Neanderthalers ever would have dreamed of, which is to go out on these big boats, way out into Arctic waters, and hunt, like, the biggest mammals on Earth. And you know haul them back in, you know, and obviously, it was enormous, like, it was better than mammoths, right? I mean a bowhead whale’s like several times larger than a woolly mammoth. So you know it was the ultimate strategy for dealing with northern environments. That was, you know, the master stroke of Inuit technology.


Amy Martin We’re going to meet more descendants of those Inuit innovators in future episodes. But first, we’re going to head in the other direction – west to Scandinavia.

Charlotta Svonni I am Sami, and my country is Sápmi, but it is divided into four countries: Norway, Sweden, Finland and Russia.

Amy Martin That’s next time on Threshold.

Nick Mott Production partners for this season of Threshold are Montana Public Radio and PRI’s The World. Thanks to them, and to the Pulitzer Center on Crisis Reporting, the Park Foundation, and to you, our listeners.

Amy Martin Threshold is created by Nick Mott, Rachel Cramer, Cheryl Skibicki and me, Amy Martin, with help from Frank Allen, Jackson Barnett, Josh Burnham, Michael Connor, Rosie Costain, Matt Herlihy, Rachel Klein, Zoë Rom, Nora Saks, Maxine Speier and Zach Wilson. Special thanks to Kristine DeLong, Joel Harper, Nate McCrady, Steve Running and Jim White. Our music is by Travis Yost.