by Chris Turney
Shackleton once remarked, “Sentiment has been the ruling force in every great work that has ever been done, and I shall be sorry when the day comes when science is divorced from sentiment or sentiment from science.” The great explorer realized science on its own was not enough. You had to engage the public, to tell a story, to get them excited in the work. A century ago, science and adventure in the Antarctic were very much one and the same thing. You couldn’t go off the map and play it safe. To be a scientist in Antarctica, you needed to be an adventurer; if you wanted an adventure, you had to have a scientific justification to get the funding. Shackleton and Mawson sold the Edwardian equivalent of space travel. No wonder the public were so excited. And they paid to make it happen.
Today we live in an age in which society is crying out for scientific solutions to global problems. The urgent need to transition to a carbon-free economy, the need to develop new drugs to combat disease, and the need to improve agricultural yields to meet the appetite of a growing world population are just a few of the many considerable challenges we confront. But in parallel to this increasing demand for science, we face a worrying trend across most of the Western world. From high schools to universities, there’s a long-term decline in the number of students of science, technology, engineering, and mathematics— the so-called STEM subjects—just when we need them most. If we’re going to sort out the big issues of tomorrow, we not only need more graduates of STEM, we need a more scientifically literate society, one that can meaningfully debate issues to make informed judgements. It’s not about knowing a random number of scientific “facts,” it’s about understanding how science works. It’s about making observations to test ideas and reach the simplest explanation; it’s about using critical thinking in all walks of life. The question is, how do you engage without making it boring? As I’ve taught around the world, I’ve become convinced that we can do more to excite students and the wider public about science and technology. We need to remember how Shackleton told stories and captured people’s imagination.
When I first started teaching at university in the late 1990s, I inherited a course on how to date geological records. Drily called Quaternary Geochronology, the ten-week lecture series was designed to show students how different scientific methods could be used to date the landscape of the last 2.6 million years. The course had been around almost as long. Passed on from staff member to staff member over the years, there were lots of incomprehensible words and mind-bending equations, and virtually no images—very little to excite anyone. I struggled with the delivery and became concerned that I was actually putting the students—and myself for that matter—off science. After a few weeks, I noticed that the only time the students woke up was at the end of each lecture when I gave an example of how a particular technique had been used. I remembered the photograph of Shackleton’s ship from my childhood. Start with the story, and then weave in the science. It was a revelation.
The next week, I tried something completely different. I was due to give a lecture on how radioactivity can be used to date rocks. Instead, I decided to go back to basics and look at the modern calendar. I started with the opening scene from the wonderful movie Monty Python and the Holy Grail in which King Arthur and his faithful sidekick Patsy ride through the mist with coconuts. The date: a questionable AD 932. Over the next hour, we looked at how civilizations had wrestled for thousands of years with developing a calendar that described time properly, something we take for granted today but which is very much rooted in science. We looked at the age of King Arthur, how Belgium missed Christmas with the introduction of the modern Gregorian calendar, and why Britain had time riots with fatal consequences—all linked to how our planet orbits the sun. The students were engaged from start to finish.
From then on, I always started with a story. The next year, I renamed the course Dating the Past, and my class numbers doubled.
Scientists need to tell stories—just like Shackleton did.
CHAPTER TWO
A Step into the Unknown
Six months after my beachside call with Chris, I was standing in front of a packed auditorium of 300 expectant faces. An Australian Broadcasting Corporation film crew were up in the wings, their camera lights blazing onto the stage. The glare was so fierce I could barely make out the figures beyond. I was hot. My mouth was parched and my palms were clammy.
How on earth did I get here?
It had been a crazy six months. With the support of Google and the University of New South Wales, the expedition went from an aspiration to reality almost overnight—and with it, the workload went into overdrive. With the launch of the Doodle4Google competition, the university was hosting my public announcement of the Australasian Antarctic Expedition 2013–2014. Personal invitations had been made across Sydney, journalists informed, and the room was packed to capacity. I could hardly believe the response. The idea of a privately funded science expedition in the spirit of Shackleton and Mawson had struck a very big chord with the public. Just a couple of hours before stepping on the stage, I’d received a letter of support from the Australian prime minister, the Honourable Julia Gillard. It was a wonderful shot in the arm, but I was terribly nervous.
I cleared my throat and tried to compose myself.
I looked down at the front row and saw Annette, Cara, and Robert smiling encouragingly back at me. It hadn’t been an easy time for the family. Preparing for the expedition had meant I’d been away a lot. And at home I’d spoken of little else; bouncing around ideas about the educational program with Annette, asking the children how best to engage with teenagers and kids. They’d all been brilliantly supportive, working up ideas for the expedition, encouraging me when I felt overwhelmed by the never-ending barrage of tasks. It was a real family effort. I don’t deserve them. I really don’t.
Right, here goes.
“Well, good evening, ladies and gentlemen . . .”
* * *
Cape Denison is as isolated, extreme, and wild as it gets—even by East Antarctic standards. Hit by wind speeds of over 200 miles an hour, “the windiest place on Earth” sits at the foot of the ice sheet, a pinprick of rock hemmed in by sheer ice cliffs at the head of Commonwealth Bay. It is one of a handful of all-too-rare natural harbors along this part of coastline. Getting there is no simple affair. Sitting at 67 degrees south—142 degrees east of Greenwich and 1,400 miles south of New Zealand—Mawson’s Antarctic base never became a permanent research station. The practical upshot is there is no airstrip, and few government vessels visit. Some cruise ships are known to dare the Southern Ocean in the summer months, but the remoteness, stormy seas, and ever-present threat of sea ice puts off all but the most adventurous of tourists.
Cape Denison may not be for the fainthearted, but it’s a magnet for Earth scientists. The violent winds that roar past it make the offshore region a prodigious producer of sea ice—one of Antarctica’s great “ice factories”—and with it one of the great drivers of our planet’s climate. What happens at Cape Denison through the seasons is an exaggerated version of what happens in Antarctica on an enormous scale each year.
With the fall of the winter sun below the horizon, air temperatures plummet, rapidly chilling the ocean and setting off a cascade of dramatic changes across the Antarctic. Pinpricks of ice crystals join to form plate-size sheets, coalescing on the surface into pancake-like shapes that ultimately become floes of ice. The scale at which sea ice is formed is truly spectacular. One month of freezing temperatures, winds, waves and snowfall is enough to create sea ice up to twenty-five inches thick. At the height of winter, it’s estimated some twenty-three square miles are produced every minute. By the end of the season, the Antarctic has effectively doubled in size, with nearly 8 million square miles of sea ice. But with the arrival of the summer sun, the system suddenly switches into reverse: warmer temperatures and the seasonal change in winds cause the sea ice to “break out” and flow north, where it melts and returns to the ocean from which it came. Each year the cyc
le is repeated: vast amounts of sea ice are formed only to melt and then reform twelve months later.
Off Cape Denison, the whole process massively speeds up. The chilling Antarctic winds that blow off the continent year-round freeze the surface of Commonwealth Bay, regardless of whether it’s winter or not: the sea ice is formed, blown offshore, a new open area of water known as a polynya is formed, and more seawater is frozen in its place. Instead of once a year, the whole cycle can take just a few days in Commonwealth Bay.
But Cape Denison is special in more ways than one. As sea ice is created offshore, a fundamental process takes place below the surface. The salt in ocean water is effectively squeezed out of the ice—a process described as “brine rejection”—creating a dense mass of water. In most of the Southern Ocean, this cold, super-salty water just diffuses away. In Commonwealth Bay, however, the conditions are perfect for the formation of something known as Antarctic Bottom Water, a key part of the ocean circulation system.
At a basic level, the world’s oceans are connected as though by one enormous conveyor belt. At one end of the loop, warm tropical waters popularly known as the Gulf Stream drift up into the North Atlantic where, over the course of a year, the evaporating surface delivers heat downwind equivalent to the output from a million power stations. It’s a major reason for the starkly different temperatures experienced along the northern fiftieth parallel; why Europe is over 30F warmer than Newfoundland and Labrador on the other side of the Atlantic. Eventually, however, this northward-flowing current becomes too cold and salty to stay afloat, and sinks, heading south miles below the surface. Antarctic Bottom Water helps drive the southern, lower limb of this conveyor belt, “recharging” the system with deep water that flows around the continent before splitting off north into the Indian and Pacific oceans to eventually warm and return to the surface, closing the loop.
Sea ice alone isn’t enough for the production of Antarctic Bottom Water, however. It needs just the right configuration of coastline and sea floor. And Commonwealth Bay has it all. Each year, the armadas of sea ice formed under the continuous blast of Antarctic winds create the densest water in the world, pouring off the continental shelf to the bottom of the sea floor. It’s estimated the polynyas in and around Commonwealth Bay produce a quarter of all Antarctic Bottom Water. This makes it a big player in the world’s climate system.
Or it should.
Everything changed with the arrival of iceberg B09B in 2011. The word “berg” doesn’t really do it justice—B09B is a monster. Weighing in at an estimated 450 billion tons, this block of ice is sixty miles long and over twelve miles wide. There’s enough freshwater in B09B to provide for all of New York’s drinking needs for 300 years. And it started out even larger. In 1987, an iceberg the size of Bali broke free from the continent in the Ross Sea. It was one of the largest bergs ever seen. Unlike sea ice, bergs are formed from continental ice, fragments of the ice sheets that cover the Antarctic, created from snowfall that’s been buried under intense pressure for thousands of years. At the edge of the continent, the ice either melts or breaks off as flat-topped or “tabular” bergs. If the balance between the lost ice and replacing snowfall falls out of balance, sea levels can either rise or fall, in contrast to sea ice which has no real impact on the world’s sea level. Riding the westward-flowing ocean currents, the Ross Sea berg smashed its way along the coast. By the time it reached Commonwealth Bay, the largest remaining part was labeled with the unassuming moniker B09B. Smashing a tongue of ice from the Mertz Glacier that extended sixty-two miles out to sea, the berg grounded itself in Commonwealth Bay. The arrival of this colossus had an immediate and devastating impact on the area. The sea ice that forms in Commonwealth Bay could no longer be swept offshore and became trapped instead. Some scientists have suggested that the arrival of B09B might have collapsed Antarctic Bottom Water production, slowing down the ocean conveyor belt that is so important to the world’s climate.
This chain of events could really help scientists understand what’s happening elsewhere in Antarctica. Since the 1970s, satellites have provided an almost daily view of what’s going on around the Antarctic. Against all expectations, and in spite of a warming world, there seems to be more sea ice surviving the East Antarctic summer each year. It’s not by a lot—some years it goes up, some years down—but the trend is unmistakably on the up at the rate of around 1 per cent each decade. It’s become so bad in some regions that government ships struggle to reach their bases. One example was at the French base Dumont d’Urville, seventy miles west of Cape Denison, where no open water was seen between March 2012 and November 2015. Air temperatures weren’t excessively cold at this time, but the “winter” ice just wouldn’t break out. In 2014, it was so bad that supplies had to be driven and helicoptered over the sea ice to keep the science program going.
The East Antarctic is throwing up a wall of ice around its perimeter and no one is quite sure why. One possibility is that the coastal underbelly of the East Antarctic ice sheet is being melted by a warming ocean. If so, the freshwater in the continental ice may be diluting the antifreeze properties of seawater, making it easier to form sea ice on the surface. Worryingly, the largest increase in sea ice appears to be happening just off the Wilkes Basin near Cape Denison—the same part of the East Antarctic that holds enough freshwater to raise global sea levels by a staggering ten feet, and an area that may have collapsed in the past, as some research has suggested. Another idea is that the winds may be playing a role. Sea ice rarely remains where it forms and is moved around by the prevailing air currents. With a change in direction or strength, sea ice can be shuffled into areas that aren’t so easily melted in the summer. Of course, both may be happening.
The bottom line is that satellites can only tell us so much. They can show us what’s happening on the surface but not under the ice, and they’re essentially silent on what happened before the 1970s. If there is going to be more sea ice off the East Antarctic in the near future, an extreme event like the arrival of B09B in Commonwealth Bay, a moment in time when the seascape froze and stayed frozen, may help scientists understand what the future will be like.
* * *
There’s an old sailor’s expression: “Below 40 degrees south there is no law, below 50 degrees south there is no God.” Since the sixteenth century, sailors have spoken in awe of the violent westerly winds and seas they experienced fighting their way across the Southern Ocean. With few landmasses to slow them down, the winds found across 40 degrees latitude often reach speeds of twenty-five knots—about 40 percent stronger than their northern hemisphere counterparts—earning them the title the “roaring forties.” As shipping pushed farther south, explorers realized that these winds form part of a vast storm belt that includes the “furious fifties” and “screaming sixties,” names more reminiscent of terrible rock bands than a major part of our planet’s circulation system. The early hunters and traders didn’t understand it at the time, but these winds are created by a procession of low-pressure systems carried east by the jet stream, a river of cold air hurtling and twisting round the Antarctic at 30,000 feet. Importantly, something quite profound appears to have been happening in recent decades: The winds seem to be getting even stronger and moving south. To properly understand what’s happening at Cape Denison and the wider East Antarctic, our expedition would have to take into account what the winds are doing over the Southern Ocean. They’re a crucial part of the bigger picture.
Trying to get a handle on what’s happening in the Southern Ocean, however, is easier said than done. Because the region is notoriously wild, it’s sparse in scientific data. Most of the records we have today come from satellite observations and sporadic records taken by ships as they hastily beat a path to safer latitudes. Fortunately, scattered across the Southern Ocean are a number of tiny pinpricks of land, the so-called subantarctic islands, many of which are home to weather stations that have been taking careful observations since the mid-twentieth century. In the southwest Pac
ific, the Australian Macquarie Island lies at the southernmost end of a chain of archipelagos extending down from New Zealand, straddling 48 to 54 degrees south, right under the path of the winds.
If we wanted to understand the changes in westerly winds and what effect this is having on the Antarctic, the expedition would have to dedicate time to the subantarctics. These islands, precious sanctuaries for wildlife and, covered in vegetation, peat bogs, and lakes, offer the possibility of finding centuries-old plant and animal remains that preserve a record of the changing impact of the roaring forties and furious fifties.
To make the most of our time south, we decided to split the expedition into two legs, to complete a scientific program that would reach all the way to the Antarctic continent. During the first ten days, we aimed to restrict ourselves to the subantarctic islands known as Snares, Auckland, and Campbell, where we’d focus our efforts on changes in the Southern Hemisphere westerlies and in the flora and fauna on these remarkable islands. Returning to New Zealand, the team would then be rotated, followed by a second, four-week voyage to work across the Southern Ocean and on to Cape Denison via Macquarie Island . . . hopefully. By dividing the expedition in two, we had maximum flexibility on who we could take. For the first leg, subantarctic experts; for the second, Antarcticians. There was also a very real fringe benefit: During the first voyage, we could give the ship and all our gear a full shake down. Any problems, and we still had a chance of getting repairs done or gaining replacements before setting out for Cape Denison. We only had one shot at this.
* * *
I’ll always remember the first time I heard the name Mawson. In 1997, Annette and I had been married one year. I had just completed my doctoral thesis and was incredibly fortunate to be offered a research position in New Zealand. Annette was pregnant with our first child, but we wanted to see as much of the world as possible, young family or not. We moved to the garden city of Christchurch, a city rich in Antarctic history, through which many of the great explorers—Shackleton, Scott, and Sir Edmund Hillary—had passed on their way to the icy continent. One evening over dinner, a friend mentioned another name: Douglas Mawson.
