Underland

by Robert Macfarlane

  He shows me a hand drill. It is a strikingly analogue tool. A 1.5-metre sleeve of metal, an internal drill bit with tool-steel teeth, a screw-form outer that guides the ice chippings up between the bit and the sleeve, and pop-out fins that prevent the torquing of the barrel when the drill is in action, but retract when it is being drawn back to the surface.

  The drill is lowered, cuts its core, is retrieved, the core is disgorged, the drill is lowered again. Lower, bite, drill, raise, disgorge; lower, bite, drill, raise, disgorge. Repeat some 700 times to bore a kilometre of ice.

  Ice-core science is industrial work, hard labour. Mulvaney once cored for ninety-two consecutive days, working up to fourteen hours a day in temperatures of -15°C. Ice-core scientists don’t tend to be the kind of people who bring workplace lawsuits because the office air conditioning is set too low for comfort.

  Ice-core science also tests patience. Once, Mulvaney tells me, he lost a drill 1,000 metres down. That was it. There was nothing to be done. It couldn’t be fetched up.

  ‘It took a year to set up the drill site, a year to drill to a kilometre, a second to lose the drill, and another year to relocate the drilling site.’

  When core is brought up it is cut into standard ‘bag’ lengths, which are then wrapped, tagged and made ready for transfer out to the cold stores of laboratories around the world. Back in the labs, each core section is cut along its length into six parts, according to a standard profile. One of these parts is known as the Forever Archive, kept in case everything else is lost. The others are used for research.

  In Greenland, Mulvaney was involved with a project known as NEEM, the North Greenland Eemian Ice Drilling Project. NEEM’s aim was to drill and analyse core from the Eemian, the last interglacial period, which extended from around 130,000 to 115,000 years ago. The Eemian is of intense interest to scientists because it is thought to approximate to the climate processes and feedbacks that may be expected by the end of the twenty-first century. It has become, says Mulvaney, ‘a hot spot for predictive research’. Fourteen nations were involved in the project.

  At the NEEM research site in north-west Greenland, a 25-foot-deep drill-pit was chainsawed out of the ice and covered to create an ‘ice cave’. Down in the ice cave, ambient temperatures were a balmy -20°C, and scientists were able to work twenty-four hours a day during the field season to extract and analyse the core. Over the course of two years they drilled more than two and a half kilometres to hit bedrock. The core they extracted was the first complete record of the Eemian.

  What that core revealed was that intense surface melt of the Greenland ice cap had occurred during the warmth of the Eemian period. The meltwater had soaked into underlying snow and refrozen, leaving tell-tale long-term signatures in the ice layers. Uncannily for the researchers, similar conditions repeated themselves during the coring work in the summer of 2012 – temperatures rose, rain fell, and the meltwater formed refrozen layers: Eemian echoes in the Anthropocene.

  Mulvaney reaches behind his computer and picks up two small objects.

  ‘Hold out your hand.’

  He drops one of the objects into my palm. It is a small, heavy grey fang. I recognize it as the tooth of a coring drill bit. The cutting edge of the tooth is deformed, like a bullet after impact.

  ‘That’s one of the drill teeth that hit bedrock in Antarctica,’ says Mulvaney proudly. ‘Nine hundred and fifty metres down below Berkner Island.’

  It looks good for nothing but spreading butter now.

  ‘Is hitting bedrock an ice-core scientist’s hallelujah moment?’ I ask. ‘Like a tycoon striking oil?’

  ‘Oh yes, there’s nothing better. Here, look at this, too.’

  He hands me the other object, a small transparent plastic phial. I hold it up to the light. It contains a pinch of blond sand.

  ‘These are the grains that came up in the last core before we hit bedrock on Berkner,’ he said. ‘This is the basal sediment. If you look at these under magnification, you’ll see that they’re rounded grains: they’re aeolian – wind-blown quartz fragments, around 0.2 milli-metres in diameter, smoothed and frosted.

  ‘Show these to any geologist, and they’ll tell you they were formed in desert-like conditions, and got rounded off by the wind. So what we know from these is that, at some point, the land that now lies a kilometre below the ice was once a Sahara.’

  ‘They’re beautiful,’ I say. ‘Desert diamonds from the bottom of the world.’

  ‘I can tell you’re not a scientist,’ he says.

  Mulvaney takes me to the cold store. We open a heavy door and push through butcher’s-shop hanging strips of heavy plastic.

  The cold of the cold store is a killing cold, a knives-under-the-skin cold, a needles-in-the-eyes cold. It is so cold the ink in my pen freezes in under a minute. Mulvaney doesn’t seem to notice. He wears a shirt with the sleeves rolled up. I am wearing three layers and wonder how long I can survive.

  Mulvaney creaks the lid off a white polystyrene chest. It is filled with core sections in marked transparent bags. He rummages, then picks out a bag. Written on the side in black marker is ‘140,000 YA’.

  ‘This one’s from well before the last interglacial,’ he says, giving it to me. I cradle it like a newborn baby, though it is very old, then I place it gently on a work surface, as far from an edge as possible.

  He slides something from a plastic sleeve and passes it to me. It is a disc of ice a few millimetres thick that has been cut from the end of a section of core.

  ‘That’s young ice,’ Mulvaney says. ‘Baby ice. Maybe 10,000 years old, no more. Hold it up to the light.’

  I lift it to the strip-light. It is instantly, witchily beautiful: silver and translucent, and seething within it like stars are scores of gleaming ice bubbles.

  ‘Those are where the real gold is stored,’ Mulvaney says. ‘Each bubble is a museum.’

  I remember Browne’s use of the word ‘conservatorie’ in Urne-Burialle, to mean a space where something is conserved. Ice has long been one of our most brilliant ‘conservatories’: ice houses kept peaches and strawberries fresh long before the invention of fridges, chilled shipping containers move luxury perishables around the world, glaciers curate the bodies of the long dead, and in cryogenic facilities, billionaires with Lazarus delusions prepare the technology necessary to freeze their brains after death. In all of these scenarios, ice serves as a substance that slows change, and reaches far into both the future and the past.

  ‘The search is now on for the oldest ice,’ says Mulvaney. ‘We want to drill to at least a million years, maybe even a million and a half, in Antarctica.

  ‘It’s a ten-year project at least,’ he continues. ‘First we need to locate the perfect drilling spot for ultra-deep drilling – and there’s plenty of dispute over that. Strangely, the Japanese think it’s near their territory, whereas the Russians think it’s around Lake Vostock, where they have their base, and the British and Americans think it’s around Dome C, where they work!’

  He speaks with pride of the achievements of ice-core science.

  ‘We helped get rid of lead in petrol. And we produced the CO2/temperature graphs that rang the bell on climate change. A few years ago, I thought my science was mostly coming to an end. What was there left to do now we’d called out global warming and cleaned up cars? Now I see a whole future opening up, in the search for the oldest ice. There’s a climate puzzle that no one has been able to solve. Around one million years ago, the climate flips its periodicity from a 40,000-year frequency to a 100,000-year frequency. Why? No one knows. And if we can’t explain that about the climate, how can we claim to know anything? If we can find and drill the oldest ice, well, we might just solve that puzzle. The secrets are in the depths.’

  Before I leave I ask Mulvaney a last question, a version of the one I asked Christopher, the dark-matter physicist, far below the earth at Boulby.

  ‘Does working in spans of time as great as those you inhabit – 100,000 years,
a million years – make the human present, our hours, our minutes, seem somehow brighter and more true, or does it crush them to irrelevance?’

  He thinks for a few moments.

  ‘Sometimes I hold a piece of rock and a piece of ice in my hand,’ he says. ‘Both have come from far under the surface, both carry messages from pre-human history. But in ten minutes’ time the ice will have vanished, while the rock will still be here.’

  Pause.

  ‘This is why ice is exciting to me and rock is not. This is why I’m a glaciologist and not a geologist. Ice still thrills me with its durability and its perishability, even after all these years and all this core.’

  ~

  Crunch and rasp of broken glass, the ice snapping at our feet. A hot, high Greenlandic sun, its light more white than yellow. Bergs in the bays, but a cloudless sky. We move in line, roped, sharp, wired.

  From the bay that morning we follow a stream uphill from camp and enter a wide valley slung between peaks. There we come upon the shores of a shallow lake, unforeseen, its far shore set tight in the shadows of the easterly peaks. It appears frozen, but on approaching I realize that what seems to be ice is in fact alluvium: silt scoured from rock by the glaciers whose melt-streams feed the lake, giving it its burnish. Our arrival sends up a flock of seagulls, wings clapping the water as they take off.

  We move along the lake’s western shore, hopping from boulder to boulder, stepping on foot-hugging cushions of moss. The low-lying flora is vibrant: slews of pink fireweed, scarlet lichen beds, yellow willows.

  An hour’s work brings us to a low pass above the lake, and there the sound of our footfalls changes as we pass onto fine gravel, beached in a gorge between boulders. We rest. Matt unslings the weapon he always carries across his back, rolls his shoulders to ease them out. The clear cries of geese can be heard, growing in strength as they near, echoing off the mountain cirque to our east.

  ‘That’s a perfect fourth!’ says Bill delightedly. He listens to landscapes like no one I have travelled with before, sees and hears them musically.

  The geese pass high overhead, a dozen or so in a tight V. I take them to be pink-foots, and guess they are beginning their autumn migration south: probably to Iceland as their next stopover, and from there to England, where they might land honking on the fields around my parents’ house in Cumbria.

  ‘This valley is one of the great highways of this region,’ says Matt. ‘For creatures and also for people. It’s the main dog-sled route from Kulusuk up to the northern fjords. From the village you come across the bay on the sea ice – if it’s thick enough – make landfall not far from our camp, then up and over this low pass and down towards Igterajipima and on towards Sermiligaq. Geo and Helen and I have done it dozens of times. We ski it all the time, too, if we don’t need the dogs. It’s like a main road for us.’

  I think of the aurora of the night before, the long green scarf that had shimmered down the length of the same valley. What was it that Barry Lopez called these old routes of movement and migration within the landscape? Corridors of breath. That was it – and the auroral light had seemed like a vivid, otherworldly breathing.

  The gravel gorge is the route of a dry glacial stream, and it leads us directly to the snout of the glacier. This is the back of Apusiajik, the landward side, where it flows eastwards off the mountain that makes it. Where the tongue of the glacier dips to meet the rock, it is dirty with dust and debris. The tongue is hollowed where meltwater streams emerge from beneath it, leaving a brown carapace of hard ice arched above mouths of melt-tunnels that lead far back under the glacier.

  We step up onto the carapace one after the other, stamping our feet, testing the ice for weakness. Each step booms, echoing through the underhang of the snout.

  When you move onto a glacier, you enter its space. Sound changes, temperature drops, danger grows. The cold comes at you not in the form of fingers, probing, but as a cloud, an aura that surrounds you and settles in your core: You’re in my zone now.

  So much of an iceberg is below the water’s surface; so much of a glacier is below the ice’s surface. As a river flows calmly over gentle ground, so does a glacier. Where it moves over steeper ground – a ‘roll-over’ – or turns a corner, the ice disrupts and cracks. Crevasses are the glacier’s equivalent of river rapids: expressions of turbulence in the flow.

  Mountaineers speak of ‘dry’ zones and ‘wet’ zones on a glacier. In the wet parts of a glacier, the ice is covered by a layer of lying snow; in dry parts, there is no such covering. Wet zones are often easier to move on, but more perilous, as the dangers of crevasse and berg-schrund are concealed, and it is hard to predict the weight-bearing qualities of the snow. When travelling on a wet glacier, the experience is one of near-continuous menace. A sense builds and stays of what lies beneath you: the great blue depths under the lying snow, the ever-present underland of ice. You are conscious of taking each step with care.

  The lower reaches of the glacier that day are dry, and so we can see down into the ice’s depths. There are little eye-shaped dolines, shimmering with cobalt meltwater. Fine fissures, only as wide as a finger or a palm or a forearm, narrow below us into blue. Crevasses yawn into chasms big enough to swallow a car or a house. Rounded pipes plunge vertically down, so straight and true it seems you might loose an arrow into one and hit bedrock.

  Everywhere the underland of the glacier declares itself less as structure than as hue, a radiant blue brimming in every fissure or shaft. In Scandinavia, this blue light is sometimes known as the ‘blood’ of the glacier: an uncanny image for an uncanny phenomenon.

  I stop to drink at a meltwater pool, dip my face to the ice, feel the blue blood-light soak into my eyes, my skull.

  Our aim that day is a nameless peak, one of the summits whose upper corries breed the ice that gathers to become the Apusiajik glacier. The only map of the region, an unreliable 1:250,000, scarcely notices it. Its summit is a graceful curve of tawny rock rising from a glaciated cirque. It is very attractive indeed – and it is just one of the countless thousands of summits that rear from the ice and the fjords up and down this coast.

  Far up the glacier we find a moulin, our first – and nothing to what we will find and descend many days later on the Knud Rasmussen glacier, far to the north of here. A moulin – the word is French for ‘mill’ – typically begins to form in a declivity on a glacier. Meltwater gathers in the declivity and, being slightly above freezing in temperature, warms the ice on which it pools. This increases the declivity, which in turn draws more water, which in turn begins to drill deeper as current and gravity come also to bear as boring forces. Under certain circumstances the meltwater will bore a hole into the glacier; grinding through the ice, sinking a shaft. Some moulins are skinny, only a few inches across. Some are hundreds of yards in diameter. Some reach only a few dozen feet into the ice before dispersing into side channels or sealing up completely. Some are up to a vertical mile in depth, and drop all the way to bedrock.

  Moulins have become increasingly of interest to glaciologists and climate scientists for two reasons. Firstly because they are signs of rising surface melt-rates on glaciers and ice caps. And secondly because the deepest moulins duct water directly to the bed of the glacier. Because the meltwater is warmer than the ice, it transports thermal energy deep into the glaciers and melts more ice – so-called cryo-hydrologic warming. It is now also understood that the water can sometimes act as a lubricant, hastening the rate at which the ice slides over the rock beneath it, such that glaciers ride their own melting.

  This quickened slide-speed can in turn quicken the rate at which glaciers calve into the sea, which in turn quickens the rate of sea-level rise. Across Greenland – as across Antarctica – glaciers are both shrinking and speeding up. The East Greenlandic glaciers presently have some of the fastest retreat rates and fastest flow rates of any on the planet. In warmer temperatures, meltwater lakes grow over days on the ice sheet, before abruptly draining through a self-create
d moulin in the course of a few hours.

  A sub-science of speleo-glaciology has emerged, with scientists abseiling into moulins to retrieve information about temperature and flow rate, or sending data monitors into their depths. In north Greenland a NASA scientist named Alberto Behar launched a flotilla of yellow rubber ducks down a mile-long moulin to see if they would emerge at the tidal snout of the glacier: a low-tech way of mapping the interior of the ice, recalling the pine cones dropped into the karst rivers of Greece and Italy to fathom their courses.

  The moulin we find that day is perhaps four feet wide, perfectly circular at the surface, and its blue shaft slides away at a diagonal into the depths of the ice. And it sings, the moulin sings, with a high, steady, neck-tingling cry. Air is moving within it and within the invisible system of melt-carved ice tunnels to which it connects, driven by water flow far down in the glacier’s tunnel system.

  Bill tilts his head towards the moulin, then looks up in wonder.

  ‘That’s an A, a D and a C sharp,’ he says. ‘It’s the harmonic series of D!’

  The moulin is a pipe of the vast aeolian organ of the glacier itself. I wish we could tune in, record its sounds, learn what it has to say.

  ‘Sea ice is incredibly musical too,’ says Helen. ‘In the winter, it really hisses and whistles – around the tideline, especially, it seems somehow to hum.’ I feel again the eerie sense of the ice as alive: the repertoire of its sounds, the variety of its forms, its colossal, shaping presence in this landscape.

  As we approach the upper cirque of glacier, the ice becomes more contorted, the crevasses almost fully covered. We move over a soft white snowfield, aware we are walking above great depth. Everyone is vigilant, keeping the rope tight in case of sudden fall. I have again a sense of doors locking behind us; remember entering other intimidating labyrinths through which I have passed – the boulder ruckle in the Mendips, the catacombs in Paris, the descent of the Abyss of Trebiciano. Here, our footprints are our Ariadne’s thread: the thin winding line that will show us the safe route out at the end of the day.