World Crack
A CRACK IN THE WORLD
AS THE ANTARCTIC HEATS UP, THE RULES OF LIFE THERE ARE BEING RIPPED APART. ALARMED SCIENTISTS AREN’T SURE WHAT ALL THE CHANGE MEANS FOR THE FUTURE.
....Trial by ice – what it takes to be an Arctic/ Antarctic Explorer
The Arctic survey team is off to the north pole, for training. They face exhaustion, numbing cold – and hungry polar bears
• The Arctic team brave polar bears to monitor acid oceans
'Nothing prepares you for the cold' . . . the The Arctic Survey team last year.
Six am on a sub-zero morning in Devon. A five-mile run in the dark, ending in a couple of hill sprints. Breakfast. Circuit training in the barn; beyond any pain threshold to physical exhaustion. Lunch. Ninety minutes dragging weighted tires up and down a 1:6 hill. The only upside is that the mud has frozen over. It's mindless, repetitive, punishing effort, not improved by an ex-marine drill sargent shouting in your ear. Tea. A three-mile run, followed by more circuits. Die. It's an environment that is. unforgiving. Die!
One day of this – well, most of it. OK then, half, and I'm shattered. For Ann D., Martin H. and Charlie P., the three members of the second 'The Arctic Survey Team' into the effects of climate change, whose latest trip to the north pole was announced yesterday, it's day six of a week-long bootcamp, by NSF. I'm just thankful to have avoided the 15-mile run across Dartmoor that entailed wading waist-deep through ice-cold rivers. B-R-R-R-R-R-RR...
You can't pull a 120kg (265 lb) sled over pressure ridges for 12 hours a day for 60 days if you're not fit. And if the three weren't polar fit when they started this camp, they certainly will be by the end. Yet fitness is just a small part of the package. Anyone – even me – could probably get fit enough if we were prepared to put the hours in, but few of us would last a day out on the ice.
Daniels is one of the world's leading polar explorers, the first woman – along with teammate Caroline H. – to reach both the north and south poles as part of all-women teams, and she readily admits there are many people out there who are a great deal fitter than her – "I'm 45 now, (45 is the new 35) for God's sake." Yet when it comes to endurance and sheer willpower, she's in a league of her own.
"You can train all you like," she says, "but nothing prepares you for the cold. On a good day it can be minus 15, on a bad day minus 45; factor in the wind chill and it can feel more like minus 70. The cold penetrates your bones and never leaves. Even when you're in your tent at night there's no respite. It's with you the whole time; you just have to try and shut it out. You can't always do it, especially towards the end of an expedition when you're exhausted."
It's the cold Hartley and Paton fear most too. They are also polar veterans and know exactly what's coming. "I'd done a lot of climbing in the Himalayas and I thought I knew all about cold," says Hartley, the expedition photographer. "But I was hopelessly unprepared the first time I went to Resolute [the settlement in the north of Canada that is the start point for Arctic exploration]. My equipment was totally inadequate and I would have died if someone hadn't lent me some warmer clothes. (When working for a company we're provided with about $2,500 + worth of extreme cold weather gear.)
"The first few weeks are bearable but once you start to get frostbite, the cold can start to affect your judgment, especially when you're living in such close proximity to other people."
British polar exploration is sometimes seen as the stamping ground of the upper-class adventurer, an image perpetuated in recent years by the successes of Sir Ranulph F. and Pen H., the director of The Arctic Survey. Daniels, Hartley and Paton don't fit the stereotype.
Daniels was a teller come bank manager's assistant until 1996 when she heard a radio advert asking for ordinary women wanting to go to the north pole; Hartley spent seven years as a studio special effects photographer before going freelance; after joining some polar trips with the marines, Paton worked out that serving in Afghanistan was a great deal riskier than a melting ice-cap at the roof of the world. For all of them – Fiennes and Hardow included – it is a full-time, professional career.
"It's not the type of job you get told about at school," Hartley says. "I started by funding myself to join expeditions to the Himalayas and the Pamirs and selling the pictures. Pen H. approached me at a talk I was giving and said, 'You must come north with me one day.' I thought he was trying to pull me and invite me to his country home. Since then I've been on something like at least 22 assignments to the Arctic and Antarctic.
"You do have to be quite selfish to do this kind of work. The expedition comes first and I forget about home life and relationships for its duration. Basically, you need to be not nearly as nice as you would like to be."
Unless you're lucky enough to have the clout to attract the sponsorship money and fix up your own gigs, your average explorer has to take the jobs that are going. You might be joining a team on a new route; you might be guiding amateurs who fork out £20,000 to be airlifted 60 miles from the pole and escorted in on foot. Or you could, like the team, become scientists for the trip – something that is more controversial than it sounds.
There's a long tradition of science in the polar regions. It's the ideal environment for everything from oceanography, astrophysics, meteorology and glaciolology to all things climate change and the Amundsen-Scott South Pole Station has been a base for scientists for more than 50 years. But the demarcation lines have always been firmly engraved in the ice. Scientists do science: explorers explore.
Hadow crossed the divide with the first The Arctic Survey last year, when his team became the first to measure ice-thickness en route to the pole – a more critical determinant than surface area of the speed at which the ice-cap is melting. Some scientists and climate change skeptics went to great lengths to rubbish their findings that the ice-cap was melting faster than previous projections had suggested, pointing to weaknesses in methodology and ridiculing equipment failures. But the survey is back again this year to continue where they left off.It sounds as if it should be a no-brainer. If you're doing science, take a scientist. It is, until you consider the conditions up north. The south pole is on a flat, frozen land mass. You can fly in directly, snuggle down in the warmth of the base and get on with your experiments. The Arctic is rather different. It is an un-mappable ocean of ice that is constantly on the move, breaking up, melting and re-forming. You can't go anywhere and expect to stay in one place. Sometimes you can only go backwards. The ice is often crushed into giant pressure ridges that take hours to cross when pulling a heavy sled and a day's hard labor can see you further away from your goal than when you started if the ice flow is against you.
It's not the sort of environment in which scientists operate. If you're measuring ice thickness and water samples, you really want to be able to go back to the same place year after year; you can't do that if the ice is constantly on the move.
"The alternative is doing nothing," says Daniels. "And that's not an option where climate change is concerned. So the expedition's goal is to take samples every day on the trek towards the pole. Charlie will be drilling through the ice to take two water samples – one at the surface and one at a depth of 10m. Some samples will be filtered for microbes, and some will be frozen to have its CO2 content analysed. It will be back-breaking work after lugging a sled for 12 hours."
Hartley will be there to record every-thing; the landscape, the water, the science. "We have a responsibility to document the Arctic ocean in summer," he says. "I've been there many times over the last few years and the ice is melting. It's a fact. It could even disappear completely in my lifetime."
The expedition comes with its own health warning. Ice floes calve, people get injured and rescue isn't always possible if a plane can't land. And then there are the polar bears.
Back at the bootcamp, two marines give us a demonstration in unarmed combat. It's all quite handy for a night out in Streatham, but not much use if a polar bear is heading your way. Even if it doesn't have a knife. So what do you do if a bear comes sneaking up on you from behind a pressure ridge?
For the first and only time, the explorers look nervous. They can see the story. Climate change explorers shoot polar bear. "Um, you would fire the gun above its head to scare it off," says Daniels eventually. And if that doesn't work? "Look," Hartley laughs. "There's no such thing as a small polar bear." Fine. So the bear gets it.
....World Crack
The warming is changing what animals eat, where they rest, and how they raise their young.
He grew up in Antarctica-and now he's leaving
Dion Poncet was born on a sailboat in Antarctica-and now his home is disappearing right in front of his eyes.
ONLINE Visit ngm.com/Nov2018 to see videos made by the National team as they traveled along the Antarctic Peninsula in 2017 on Dion Poncet’s boat. Dion Poncet came of age in a place almost no one calls home.
HE WAS BORN ON A SAILBOAT in Leith Harbour, an abandoned whaling station on South Georgia island. His father, a French adventurer, had met his mother, an Australian zoologist, on a jetty in Tasmania while sailing his boat around the world. The couple started a family in the South Atlantic. For years they traversed the west coast of the Antarctic Peninsula, surveying wildlife in uncharted bays—seals, flowering plants, seabirds—with three boys in tow. Dion was the first.
The Antarctic Peninsula is an 800-mile string of mountains and volcanoes that juts north from the White Continent like the tail on a horseshoe crab. It was Poncet’s playground. Young Dion and his brothers read, drew, and played with Legos—but also chased penguins, lifted chocolate from derelict research stations, and sledded down hills that might never have seen a human footprint. Other kids face schoolyard bullies; Dion was tormented by dive-bombing skuas, which whacked his head hard enough to make him cry. Other kids star in wobbly home movies; the Poncet boys were featured in a 1990 film about growing up in the Antarctic. Sometimes, during breaks from homeschooling, Dion’s mom had him count penguins. “It got pretty boring pretty quickly,” he says.
On a frigid evening nearly 30 years later, Poncet and I stood in the wheelhouse of his 87-foot boat, the Hans Hansson, scanning the ice for Adélie penguins. At 39, Poncet is blond, block-jawed, and quiet, with enormous hands. He has spent much of his adult life ferrying scientists and other visitors in charter boats through the waters around South Georgia and Antarctica from his base in the Falklands. Along with a team of photographers led by Paul Nicklen, I had joined him for a voyage along the west coast of the Antarctic Peninsula. We wanted to see how things were changing in a region he’d known his whole life.
Here at the bottom of the world, a place all but free of human settlement, humanity is scrambling one of the ocean’s richest wildernesses. Fossil-fuel burning thousands of miles away is heating up the western peninsula faster than almost anywhere else. (Only the Arctic compares.) The warming is yanking apart the gears of a complex ecological machine, changing what animals eat, where they rest, how they raise their young, even how they interact. At the same time, the shrimplike krill upon which almost all animals here depend for food are being swept up by trawlers from distant nations. They’re being processed into dietary supplements and pharmaceuticals, and fed to salmon in Norwegian fjords and to tropical fish in aquariums.
So much here is changing so fast that scientists can’t predict where it’s all headed. “Something dramatic is under way,” says Heather Lynch, a penguin biologist at Stony Brook University. “It should bother us that we don’t really know what’s going on.”
What we can see is troubling enough. On the western peninsula, Adélie penguin populations have collapsed, some by 90 percent or more. Records of great hordes of the birds in one bay date back to 1904; today in that spot “there are only about six nests left,” Poncet says. That day in the wheelhouse, when Poncet and I spotted our first massive colony, we had left the west for the peninsula’s northeast tip.
On tiny Paulet Island, thousands of penguins were perched in rows up a rocky slope, evenly spaced, like an audience at an opera house. We could see some wandering the remains of an old stone hut built in 1903 by shipwrecked Swedish explorers, who survived a long Antarctic winter by eating penguins. On an iceberg off our starboard beam, a noisy cluster of penguins slipped and knocked about like wobbly bowling pins. When I saw one glissade down polished ice, its flippers pulled back in a skier’s tuck, then tumble into a trio of fellow birds, I laughed out loud. Poncet just nodded.
Antarctica is not all death and chaos: Millions of Adélies still thrive around the continent, performing their unintentional comedy. But the western peninsula’s transformation is profound, and few have seen more of it unfold than Poncet. The world he once knew is unraveling. He speaks of the loss like a farm kid who has watched suburbia gobble the family homestead.
“All the things you used to experience, the places I went when I was a child—I took it for granted then,” Poncet says. “Now you realize it’s not ever going to be possible again.”
MUCH OF ANTARCTICA is a vast plateau, a high desolate desert of blowing snow where temperatures can plunge to minus 140°F. Poncet’s Antarctica isn’t like that at all.
The Antarctic Peninsula is longer than Italy and curls north toward the temperate zone. Its climate—for Antarctica—has always been mild. Summer temperatures often rise above freezing. Isolated patches of vegetation dot exposed granite and basalt. Adélie penguins live all along the coast of Antarctica, but the peninsula also supports species the harsh mainland can’t: fur seals, elephant seals, gentoo and chinstrap penguins. Petrels and sheathbills flit about the skies. All this life relies on the sea.
WARMING LANDS
As the sea ice season off the west coast of the Antarctic Peninsula shrinks, species that rely on the ice will have to adapt or perish. The loss of ice could also reduce krill populations. Many species consume these tiny crustaceans, which for now are still abundant.
Sea change
Global warming is heating deep waters circulating from northern oceans. As winds blow away colder surface water, the warmer waters rise from below, making sea ice and glacial ice thinner. A warming climate also increases storminess, which pushes sea ice south.
Prey under pressure
The ice-free fishing season now extends deeper into fall. Strict quotas limit krill catch size, but the shorter sea ice season and the longer fishing season could put humans and wildlife in more competition for the same prey.
Winners and losers
Animals that hunt in open water and breed on rocky shores along the western Antarctic Peninsula may fare well as sea ice retreats. Others that depend on sea ice for food, protection, and a place to rest will likely face decline.
On the rugged peninsula, Antarctica’s stillness is punctuated by squawking and chattering and concentrated motion. It’s a place of bizarre angles: Blue-white glaciers flow to the ocean and calve into icebergs that assume every form imaginable. Bergs the size of small towns reach into the clouds. Even dozens of miles away, you hear them crack and explode like cannons.
It looks like wilderness, and it is, but it is not untouched. People began altering life in this region decades before anyone had even seen Antarctica. Not long after Capt. James Cook first cut through Antarctic waters in the 1770s, hunters started slaughtering fur seals by the millions, mostly for hats and coats. They also killed elephant seals for oil, to be used in paint and soap. The first to set foot on the continent were probably Connecticut seal hunters who came ashore briefly on the western peninsula in 1821.
In time whalers began harpooning sei whales, blues, fins, and humpbacks. They stripped baleen, or whalebone, from their mouths to make whips, umbrella ribs, corsets, and carriage springs and used the whale oil for heat, lamps, and margarine. In the early 20th century South Georgia became a whaling mecca. Leith Harbour was the last of its stations to close, in 1966.
Climate change has since left an unmistakable mark. Winter air on the western peninsula has warmed more than 10 degrees Fahrenheit since the 1950s. Winds drive changes in ocean circulation that bring warmer deep water toward the surface, helping to reduce sea ice—the broken crust that forms when the ocean’s briny surface freezes. Sea ice now appears later and disappears faster: The ice-free season on the western peninsula lasts a full 90 days longer than in 1979. For a Northern Hemisphere equivalent, imagine summer suddenly stretching to Christmas.
The winter before Poncet was born, his parents spent weeks camping and exploring frozen Marguerite Bay, hauling gear by sledge across its solid surface. “Nowadays,” Poncet says, “that’s finished. Sea ice barely even forms.” The loss of ice exposes warm water to the cold air, increasing evaporation, which returns to the world’s driest continent as snow—even rain. On a 2016 trip to Marguerite Bay, halfway down the west coast, Poncet faced a deluge that lasted almost a week. “Thirty years ago I don’t think anyone had ever seen a drop of water fall from the sky down there,” he says.
The balmier water pulled from the deep even affects ice on land, by attacking glaciers where they meet the sea as floating shelves. At least 596 of the western peninsula’s 674 glaciers are in retreat, according to a British survey. Else-where in Antarctica, far larger ice shelves are thawing and crumbling, threatening a rapid rise in global sea levels. On the east coast of the peninsula itself, ice has been failing spectacularly ectacularly too—a Delaware-size piece broke off the Larsen C Ice Shelf just last year. But the east coast can still be five degrees Fahrenheit cooler than the west. Prevailing winds often push sea ice from the west around the tip of the peninsula to the east, where a gyre traps it against land.
The western peninsula is Antarctica’s hot spot. Often depicted on maps in white, it’s now so warm that tufts of the continent’s only native flowering plants, hair grass and yellow-flowered pearlwort, are spreading. So are invasive grasses and lichens. Green moss is growing three times as fast as it did in the past. Island peaks once cloaked in snow are now wet and melting, exposing mud or yawning crevasses.
“The landscape is shriveling,” Poncet says.
Hiking recently on the south shore of Elephant Island, off the tip of the peninsula, Poncet was flabbergasted by how temperate things seemed. The weather was humid, the landscape ice free, and enough grass had sprouted that it brought to mind a meadow.
“It didn’t feel like Antarctica at all,” he says.
A HEAVY RAIN is falling as we depart the Hans Hansson one morning on black rubber rafts, bound for a pebbly shore near the Antarctic Sound, at the northern tip of the peninsula. On a rocky shelf colored like a sunset by streaks of guano, we spy several muddy Adélie penguins. One is a fledgling, whose gray, pillowy down is damp and matted.
Adélies are the peninsula’s only truly Antarctic penguin species. (Chinstraps also live in South America; red-beaked gentoos range from there to Africa.) They build nests of pebbles and return to the same site each year at the same time, even if it’s raining or snowing or ice is melting. They prefer dry rock or soil but now are often forced to build on light snow—only to have nests collapse when the snow melts or fill like ponds when it rains. Adélie eggs are drowning in flooded nests. Drenched and windblown chicks are freezing to death; they lack the moisture-repelling feathers that protect adults.
Adults, meanwhile, struggle with lost sea ice. Adélies molt on floes far at sea and use ice as way stations to avoid predators between hunts. They can swim for days but tend to dive only in the upper few hundred feet of sea. As waters warm, more adaptable penguins are pushing in. Gentoos—fat, tall generalists—are more flexible about when and where they build nests and are more apt to lay new eggs if nesting fails. They hunt closer to land and eat whatever is available. From 1982 to 2017, the number of breeding pairs of Adélies along the western peninsula and South Shetland Islands dropped by more than 70 percent, from 105,000 to 30,000. Gentoo pairs saw a sixfold increase, from 25,000 to 173,000.
Ice is essential to more than just Adélies. It’s as central to this region as grass is to the savanna. When it disappears, relationships can shift unpredictably. One morning near the Antarctic Sound, Nicklen, photographer Keith Ladzinski, and I zip into dry suits and go snorkeling near shore. We watch a skittish Adélie survey the waves from a crumbling raft of ice. The bird seems hesitant to plunge in—with good reason. A leopard seal is circling and occasionally nosing onto the ice.
A leopard seal can weigh half as much as a small car. Its toothy jaws open wider than a grizzly bear’s. When closed, its mouth curves in a mischievous smile. That’s how the predator looks as it corkscrews around us—rakish, impatient, the king of its domain.
Suddenly, two more leopard seals appear. They turn in lazy laps, spiraling one after the other. Soon there are two more, their eyes locked on other penguins. One by one, the birds slip into the water, and the seals give chase. Some penguins turn and scamper back to ice and safety. Others aren’t so lucky. In an area not much bigger than two suburban backyards, five seals are soon feasting on penguins, shaking and shredding their bloody prey.
The show is mesmerizing—and “highly unusual,” Tracey Rogers, a leopard seal expert at the University of New South Wales, later tells me. Leopard seals, like grizzlies, are solitary creatures that usually stake out vast territories offshore. They need ice floes to rest on between hunts. Loss of ice from climate change is leading them to congregate near land, shifting how, where, and even what they hunt.
Leopard seals used to be rarely seen near fur seal breeding grounds. “Some sealers in the 1800s kept meticulous logs and records,” says Doug Krause, a wildlife biologist with the National Oceanic and Atmospheric Administration. “None of them reported seeing leopard seals hanging around.” Now, 60 to 80 leopard seals wriggle ashore every year at Cape Shirreff, in the South Shetlands. At the region’s largest fur-seal breeding ground, they kill more than half the newborn pups.
After commercial sealing stopped in Antarctica in the 1950s, fur seals started making a triumphant comeback. Scientists thought they would adapt well to a warming climate. Now their numbers at Cape Shirreff are declining 10 percent each year. “What we’re seeing is extraordinary,” Krause says. “No one saw this coming.”
NO ONE FORESAW the good news either—the boom in humpback whales.
Starting in the early 20th century, industrial whalers drove most of Antarctica’s cetaceans nearly to extinction, and many species are still struggling. Blue whales, for example, are thought to have numbered about a quarter of a million around 1900; the population today is 5 percent of that. But Antarctic humpbacks are roaring back: Their population is rising by 7 to 10 percent a year. “They’re going bonkers!” Ari Friedlaender shouts as we dart across the water in an open skiff in the Palmer Archipelago, where we rendezvoused with him.
Friedlaender, a marine ecologist with the University of California at Santa Cruz and an Explorer, has been studying humpbacks off Antarctica since 2001, tracking how and where they move and feed. He has recorded them rolling and playing with one another and diving deeper than anyone expected. He’s seen them opening gashes in ice with their blowholes. For animals that can weigh up to 40 tons, all this requires a lot of energy—and for now, he says, climate change is making more fuel available.
Friedlaender saw his first sign of that on a cruise in May 2009. It was late fall, so he and his colleagues assumed the humpbacks would have long since left for their wintering grounds near Ecuador and Panama. Then an echosounder detected a blob of krill that spread for miles below the ship. “We woke the next day, and there were more whales than any of us had ever seen at any time, at any place on the planet,” says Friedlaender, who has also studied them off Alaska, California, and New England. They counted 306 humpbacks in a 10-mile stretch. “They were here because there was no ice.”
Humpbacks, he explains, used to leave Antarctica in late March or early April, when sea ice closed in. Now they have many more ice-free weeks with more open water in which to roam widely and feed on krill. Those beady-eyed, translucent creatures are the size of a child’s pinkie, but they travel in thick swarms that can stretch for miles, with 78,000 or more in a single cubic yard. Humpbacks are sticking around and fattening up on krill, and that’s fueling a population boom. Female whales are producing calves every year. Lactating mothers have so much strength they’re feeding newborns while pregnant. “That’s insane for an animal that big,” Friedlaender says.
He pulls alongside a humpback and her calf, resting in brash ice. The skiff bobs as Friedlaender, like some ponytailed modern harpooner, raises a long shaft above his head. The business end holds a waterproof camera fitted with suction cups. Friedlaender steadies his quivering weapon, takes aim, then slaps the camera on the leviathan’s back. The surprised whale makes a sound like a wet snore. Both mother and calf dive. “Felt like a great stick!” Friedlaender yells. For a day or two, until it falls off and floats to the surface to be retrieved, the camera will record a whale’s-eye view of the sea. Humpbacks fare far and deep with few natural competitors. But how well they fare now depends on us.
A FEW YEARS AGO, an icebreaker dragged research nets around the Palmer Archipelago, looking for Antarctic silverfish—oily, sardinelike creatures that spawn beneath sea ice. They used to be the dominant fish off the western peninsula, composing half of what some Adélie penguins ate. But the team, led by Joseph Torres of the University of South Florida, towed day and night around Anvers and Renaud Islands and never caught a single silverfish. In waters that have experienced some of the greatest sea-ice declines, the fish had all but disappeared. Meanwhile scientists noticed penguins gulping more krill—even though it can take 20 krill to match the caloric value of one silverfish.
Will there be enough krill to go around? It’s not an easy question. Penguins and humpbacks eat krill, but so do skuas, squid, fur seals, and crabeater seals. Leopard seals sometimes eat krill. A blue whale eats millions a day. Animals that don’t eat krill often feed on prey that does. Antarctica loves fatty krill. So do we.
In the 1960s, seeing a potential new seafood source, Soviet fleets began circling the continent. Today about 10 ships a year catch krill, led by Norway, South Korea, China, Chile, and Ukraine. The catch turns up in omega-3 pills and chewable krill-oil gummies and farmed salmon. In Ukraine peeled krill is sold in tins, like sardines. Sometimes krill gets processed at sea, boiled and dried into powder on huge trawlers.
After almost a month at sea we finally see one, in the Bransfield Strait, off the South Shetlands. A storm rocks the 333-foot Long Da, a Chinese mid-water factory trawler, as we pull along her stern. The boat’s net courses through the water like a gape-mouthed whale shark. As the crew haul it in, the net’s green mesh curls over itself, cocooning millions of krill.
For now, krill around Antarctica remain abundant. Trawlers net only a tiny fraction of the continent’s krill. Fishing is tightly managed by 24 countries and the European Union, organized as the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). But krill populations are cyclical, and researchers can’t say how quickly or severely warming and loss of ice may affect them. “We measure krill and may think we understand it, but we don’t, really,” says Christian Reiss of NOAA Fisheries.
Many experts worry that krill boats could target and deplete krill on feeding grounds important for other wildlife. A team of U.S. government scientists in 2017 put it bluntly: “If predators and the fishery use the same population of krill, it follows that removal of krill by one group may limit the availability to the other.” Most fishing takes place where climate change has stressed animals the most—near the western peninsula. “Where is there also one of the greatest densities of predators?” Friedlaender asks. “Same place.”
In 2017 Chile and Argentina proposed that CCAMLR place thousands of square miles west and north of the peninsula off-limits to krill fishing. Just this summer, environmental groups and Norway’s AkerBioMarine, the largest krill-fishing company in the world, helped persuade most others in the krill industry to avoid fishing near penguin colonies during breeding periods next year. Starting in 2020, the companies say, they will stay at least 30 kilometers, or 19 miles, from penguin colonies year-round.
Many scientists and wildlife advocates maintain that permanent no-fishing zones regulated by CCAMLR are the safest solution. Otherwise, says Kim Bernard, an Oregon State University oceanographer who studies krill, “things could go very badly here. That really scares me.”
ONE EVENING ON THE Hans Hansson, after a dinner of lamb and potatoes, Poncet traces a map in the galley, pointing out places he once chased krill with a butterfly net. It was common when he was a child to see massive swarms at the surface, he says. “Sometimes the engine would overheat because the water intakes were blocked with krill,” Poncet recalls. Today “you almost never see them” in those places.
Scientists take Poncet’s long experience seriously. “In a way, it’s traditional knowledge,” Bernard says. As Antarctica hurtles toward the unknown, scientific knowledge is still sparse.
This year Poncet abruptly sold the Hans Hansson. He says he and his companion, Juliet Hennequin—also an accomplished boat captain—were exhausted. But he also felt that too many visitors took the region’s bounty for granted, just as it was changing into a place he barely recognized. “When I take stock of the current situation, the Antarctic Peninsula I knew as a child has already largely gone,” he says. “I do wonder a lot what it will become.”
.....Environment: Scientists caught an Antarctic ice shelf singing a strange tune
This bizarre phenomenon could better predict how quickly the planet’s ice is melting into the ocean.
A man holding machine on icy plain
Seismometer, being used to measure vibrations that travel through the Earth.
Antarctica is honestly kind of creepy. It’s leaking from the inside; it loves to ooze some bloody liquids out into the ocean like some gargantuan stabbing victim; it’s a dry hellscape despite being covered in a thick layer of literal water (albeit the frozen variety); and now it turns out Antarctica is an avid whistler of some eerie tunes. Bear with me: a new study published in Geophysical Review Letters this week details how scientists have picked up on strange tones resonating near the surface ofthe massive Ross Ice Shelf in Antarctica. While these wintery sounds have their place in the wintery landscape, you can banish the idea of anything resembling Frozen—these songs are more of the inaudible-to-human-ears type.
“Ice shelves are a critical element of the Antarctic glacier system,” says Rick Aster, a geophysicist at Colorado State University and a coauthor of the new study. “We care deeply about them because their stability in decades to come will substantially affect global sea level rise and other issues that affect millions. This discovery provides a new tool to measure and understand how they are affected by warming in the atmosphere and oceans.”
Lead investigator Julien Chaput, a geophysicist at the University of Texas, El Paso who began this work under Aster at CSU, describes the study as a “bit of a happy accident,” stemming from a broadband seismic instrument deployment on the Ross Ice Shelf, which is roughly the size of Texas, to study the crust and mantle underneath. Chaput, an expert in ambient noise monitoring, started noticing “strange spectral anomalies that escaped easy explanations,” suggesting some sort of high-frequency seismic waves were persistently trapped in the firn (the top couple of meters of snow).
“The end result was really just the outcome of chasing a cryptic puzzle,” he says. “Chasing down that lead gave us a unique insight into all the environmental effects an ice shelf can ‘feel,’ and on remarkably short time scales.”
The team eventually found that these trapped firn waves were created by the constant hum of wind brushing against the snow on the surface of the shelf. These sounds have been recorded before in other areas of the world, including Antarctica, but this research found that the tones were changing over time, in direct response to what was going on in the environment.
In Antarctica, movements on the surface can often be translated into vibrations that propagate throughout the ice shelf. The frequency of these waves vary based on changes to the loose snow in the firn, including the impacts of heavy winds or temperature shifts. The team measured the vibrations (aka seismic waves) that moved through the shelf for a little over two years, and were able to detect in what ways the frequency shifted based on nasty storm events or heavy winds, seasonal changes or unusual shakeups in average temperatures, and so forth.
“This last point is particularly interesting,” says Chaput, “because it could allow us to quantify which ice shelves have firn layers that are strongly impacted by repeated warming events, and also yield a metric of how resilient these firn layers might be.”
These effects were perhaps crystallized best in observations made in January 2016, during a particularly warm period when temperatures rose slightly above freezing, and allowed a bit of the snow and ice to melt. The melting slowed down the seismic waves and changed their pitch. But when temperatures rose once more, the waves didn’t revert back to their previous state. The firn had been altered permanently, and the ice shelf song was changed permanently as well.
The study is a particularly good illustration of why it would be useful to use seismic observations to keep a close eye on firn, all over the world. Firn melt is broadly considered by scientists to be one of the most important factors in the destabilization of an ice shelf. And ice shelves themselves are particularly important, since their melting accelerates the streaming of ice into the ocean from abutting ice sheets. Recent years have highlighted the role of ice shelves as the “real heavy hitters in any potential sea rise,” says Chaput, and he’s encouraged by the notion of using this technique to study ice melt broadly across the globe. He hopes future researchers might be able to spot melting pockets or cracks that are forewarning signs of a larger shelf breakup, be it in Antarctica or Greenland or wherever else.
“Polar environments are more or less the vanguard of climate change, but instrumentation and modeling of these environments has lagged behind by quite a margin,” says Chaput. “We all know we're in hot water—the problem is, we're not really sure how hot it is yet.” He cites the collapse of Larsen B in 2002 as a prime example of how limited we’ve been in really spotting and gauging the loss of ice mass as it occurs.
“In a sense, this way of looking at continuous seismic data could be considered a ‘canary in the mines’ sort of observation, with almost real time temporal resolution,” he says. “Deploying a single seismometer on an ice shelf could provide the means of observing very subtle environmental forcing, on time scales as short as minutes, and would provide a means to directly understand the sequence of physical changes that happen in the near surface as a melting event strikes.”
There’s a lot of work that needs to take place to really prove how viable seismological observation could be for monitoring ice melt, but it’s probably a safe bet to follow the humming. If the ice is going to be singing aloud, we may as well keep an ear out and listen closely.
.....Photographer is still awestruck by his face time with a leopard seal in 2006, a Antarctic veteran. This was some ones first trip.
The nonprofit Universal Society, working to conserve Earth’s resources, helped fund this article and others.
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