Ends of the Earth: Journeys to the Polar Regions in Search of Life, the Cosmos, and Our Future

by Neil Shubin

I’ve proceeded from that rookie experience in Greenland to lead my own expeditions in the Arctic and Antarctica over the past three decades, my original trepidation has been replaced with gratitude for the privilege of working in some of the most extraordinary landscapes on Earth. How many times can you work in places that few, if any, humans have ever encountered before? And to do that exploration in the service of understanding the fundamentals of our world and the ways it came to be?

Stating that the sole purpose of any nation’s use of Antarctica is for scientific discovery alone, the Antarctic Treaty was signed by twelve nations in 1959.

In this book, polar science will be our lens to see the natural world and the extraordinary ways we have come to know it. We will see how work in the Arctic and Antarctica reveals profound connections among oceans, climate, and all living beings—a delicate network that will shape the coming centuries on our planet.

Ever since humans first set foot on polar landscapes, scientific insights have been gained by researchers often isolated in small field camps or stations, living in environments that can freeze flesh in minutes, and jury-rigging failed equipment to keep life and work going in adverse conditions. Scientific discovery itself has become the product of another kind of science—that of polar exploration. Success comes from employing techniques and ideas developed by Indigenous Peoples who first settled the region thousands of years ago and the European explorers who followed them centuries later. Across time, humanity has expanded its knowledge of the world at the poles through endurance, resilience, serendipity, and tragedy.

each week of fieldwork involves several weeks at home planning. And still, wonderfully detailed itineraries, field lists, and objectives go out the window as soon as one sets foot on the ground. As Mike Tyson once famously said about boxing, “Everybody has a plan until they get punched in the face.”

The continuous light of the sun, coupled with the vastness of the landscape, brings an almost boundless metabolic energy that powers long hikes, intense conversations, and deep companionship.

The world becomes small and intense—defined by the colleagues on the expedition, the supplies and gear that we bring, and the rocks, rivers, and tundra that are accessible on foot. With these local and intimate interactions, the landscape—its shapes, textures, and rhythms—gains a personality, almost like a member of the expedition. The shifting weather and light of the Arctic and Antarctic shapes our work, lives, even our emotional states. With no news, internet, or external sources of information, the main distractions in camp are the ones we carry inside of us.

sunlight that arrives at the Antarctic continent at an angle of 30 degrees on a cloudless summer day carries half as much energy as that which falls on the surface near the equator. Because polar regions receive far less energy from the sun throughout the year than other parts of the Earth, the poles are low-energy places. Creatures that live there either find new ways to produce energy, conserve it, or learn to live with little of it.

The energy on the surface of the planet ultimately comes from the sun, and polar regions have no incoming solar energy for months at a time. Living things run on a kind of fuel reserve during these dark periods.

Polar regions encompass 8 percent of the total surface of the Earth but hold an outsized influence on the state of the planet. Almost 70 percent of all the planet’s fresh water is frozen in ice. On land, permafrost in the polar regions holds 1,600 billion tons of carbon—roughly double that in the entire atmosphere today.

Humanity’s experience with glacial ice, both on mountaintops and at the poles, is a story of adventure, tragedy, and scientific observation.

McMurdo is the port of entry for most expeditions on the ice, and it feels like a waystation similar to the fictional Mos Eisley spaceport in Star Wars or Rick’s Café from Casablanca. The entire population is temporary: those in transit to field sites, such as me and my team, interact with people who are on base for six months or more and maintain and support its operations. Many people are waiting for flights into the field, others for flights home.

Each year, several expeditions get stuck on the base for months, or never get into the field because of equipment failures or weather changes. Some arrive at McMurdo only to find their entire scientific project scuttled because a part for an experiment didn’t arrive or the weather where they want to work is too forbidding.

because pressure and temperature are related physically, ice under pressure melts at an even lower temperature. Ice lining the bottom of a glacier sits at such high pressure that it is right on the cusp of melting. The fact that “ice is hot” spawned one of the most vicious scientific debates of all time.

look for fossil fish near the poles, the movement of the continents during Earth’s history means that rocks that formed near the equator millions of years ago can now be found at high northern and southern latitudes. After my colleagues and I discovered the fishapod—a 375-million-year-old fish with arms and legs—in rocks in the Canadian Arctic in 2004, we later found scientific papers attesting to similar rocks in Antarctica.

Frozen water absorbs all other wavelengths of light, leaving blue reflected.

Blue ice is so frictionless that even the simplest motion becomes fraught. There is absolutely no way of getting enough traction to move on a flat patch of it. Crampons often don’t work because they cannot etch into the ice’s rock-hard surface. Snowmobiles caught on a slope of blue ice have been known to slide hundreds of feet downhill.

Occasionally, an ice floe will hit an obstruction such as a mountain range and blue ice will extrude upward from the deep layers of the glacier. This ice can rise vertically hundreds, if not thousands, of feet. The deepest layers hold the most dense, hard, and ancient blue ice—some of it is more than 6 million years old.

At the base of a mountain in Antarctica there’s the pervasive threat of disastrous winds, sometimes over 100 miles per hour, that not only can stop work but can wipe out a camp. Ice at elevation makes the surrounding air cold and very dense. That dense air can flow downhill and, gaining speed as it descends, generating intense windstorms in the floor of a valley. Forrest was famously caught in an Antarctic gale that sent his team’s snowmobiles flying though the sky.

A set of parallel valleys, covering almost 2,000 square miles, lies 40 miles west of McMurdo Station. While these valleys are flanked by ice, their walls and floors are pure bedrock with barely a patch of ice inside. The area looks like the surface of a rocky, lifeless desert. In winter, temperatures here can drop to −90 degrees Fahrenheit. The region is so cold and barren, it is used to model the geology and possibilities for life on Mars. The landscape of these valleys, known as the Dry Valleys, appears as a paradox. If ice lies on the mountains above the valleys, and their interior gets extremely cold, why is there no ice within the valleys themselves?

If there’s a Murphy’s Law of paleontology, it is that the best fossils are often found at the tops of mountains. Our fossil site was no exception.

An ancient tropical river once teeming with life is now a rock layer lying atop an Antarctic peak surrounded by ice that extends hundreds of miles to the South Pole.

The tops of these mountains contain rocks formed in ancient rivers and streams and hold fossils of ancient fish and sharks.

Math, as he was told by his teachers in France, was a ticket to interesting careers. And in his case, it was—the discipline opened doors for him to explore his passions in engineering, aeronautics, and astronomy.

If the same spot is measured several times, the signals can be combined to reveal the velocity at which objects below are moving. The technique can be so precise that changes on the order of a millimeter can be measured from space.

Rignot and his team at JPL, NASA, and international space agencies scanned the satellite data to make detailed measurements of the movement of ice across the entire continent of Antarctica between 2007 and 2009.

The satellites reveal that the entire ice sheet of Antarctica is continually on the move from the center of the continent to the ocean. If you put a boulder that could be traced year after year at the South Pole, it would end up in the ocean within one hundred years.

When the ice hits a mountain or some other obstruction, the conveyor belt continues and it flows around the obstacle while some ice from the deepest layers wells up. These regions also develop cracks, crevasses, and ice cliffs where the ice folds and bends.

The greatest change in the height of the ice, meaning the fastest melt, happens along the coastline, where the ice meets the ocean. Changes at the coast then propagate inland to the center of the ice sheet. The “business end” of the ice sheet is where it meets the warm water of the ocean.

These satellites monitor gravity and mass 24 hours a day, 7 days a week, 365 days a year. We now have a continuous record of changes in the mass of polar ice over time. The GRACE missions send data that Rignot calls a “Weather Report” of the changes to the mass of ice in Antarctica and Greenland.

These satellites are nicked “Tom and Jerry”. Where “Tom” follows (chases) “Jerry” by 140 miles.

At the coast, ice meets the sea and liquid water interacts with solid ice. The melting here is the most dramatic because the warmth of the ocean causes the edge of the glacier to thin, collapse, and crumble into the sea. Melt can also happen from below when the relatively warm water of the ocean flows underneath the glacier between the bedrock floor and the ice. This melt can set off a chain reaction: the more the leading edge collapses, the faster the ice streams will bring ice from the interior to the coast, leading to more ice interacting with the warm ocean waters. Some coastal glaciers, such as the Cadman Glacier, have lost as much as 60 feet of height—the equivalent of a five-story building—in a single year.

H. P. Lovecraft had published his classic horror novel At the Mountains of Madness, in which geologists from Arkham’s Miskatonic University uncover alien civilizations under the ice. These kinds of fictional accounts and popular myths of subglacial military bases, alien spacecraft, and lost civilizations in Antarctica have been a common theme in popular culture.

the work of physicists such as Lord Kelvin in England, who speculated that ice under pressure can transform into liquid water deep inside glaciers.

Expeditions were returning from Antarctica revealing a continent of ice. Kropotkin saw something else. He proposed that underneath the ice of Antarctica sat vast lakes—entire worlds sealed off from Earth’s surface.

In 1957, after the signing of the Antarctic Treaty, Russia built the first of its Antarctic research stations. One of them, named Vostok (Russian for “east”) after the ship of the First Russian Antarctic Expedition in 1820, has the reputation of sitting on the most extreme and dangerous place on the continent, if not the entire planet. Located nearly 12,000 feet above sea level, on a distant part of the ice cap, Vostok has experienced the lowest temperatures ever recorded on planet Earth: –127 degrees Fahrenheit.

The ice at Vostok is almost 12,000 feet thick, and the lake sits almost two miles below the surface. Dubbed Lake Vostok, the sixth largest freshwater body in the world by volume, it is roughly the size of Lake Ontario. We now know that the lake contains several islands and is one of four hundred freshwater lakes under the Antarctic Ice Sheet. Some of them, such as Lake Vostok, may have been separated from the world above for over 15 million years.

In Vostok, drilling takes decades and is fraught with potential contamination issues, logistic challenges, and political entanglements. Priscu’s idea was to identify subglacial lakes that were not as deep as Lake Vostok, that were more easily accessible logistically, and where he could deploy sterile drilling technologies. Subglacial Lake Whillans fit the bill. This lake sits 300 miles from the South Pole and is within a two-week tractor drive over the ice from McMurdo Station. Supplies could be ferried there much more easily than to Vostok. Moreover, radar and seismic studies revealed that Whillans is buried under only an estimated 1,800 feet of ice.

DNA sequencing revealed nearly four thousand species living in Lake Whillans under the ice. Priscu’s team was able to isolate and grow thirteen of them in the laboratory.

Being removed from the sun as a source of energy, these species evolved ways to extract energy by metabolizing the ammonium, sulfur, and iron in the lake waters.

They have the remarkable ability to shut their metabolism off and hibernate for almost five years. They can survive in places and conditions where other animals will perish: from extreme heat up to 304 degrees Fahrenheit to extraordinary cold down to –328 degrees Fahrenheit. They’ve even been shown to be able to survive in the vacuum of space.

Tartigrades.

the Russians were continuing with their own drilling at Vostok. In 2012, the Vostok team hit water. The hole had to be closed as the extreme weather was setting in and the team had to depart for the season.

an isolated red island grew ever larger in the distance. Sitting like a red bull’s-eye on the edge of a glacier, the shape of the feature emerged as we approached. One of the glaciers terminated in a cliff that rose about five stories high and stood out from all the rest for hundreds of miles. A river of red spewed out of the top, almost as if thousands of gallons of paint were gushing from its insides. Blood Falls was appropriately named.

they contain a high concentration of iron. This fact explains the red color. The iron in the water is derived from the iron-rich rocks below the glacier. When the waters emerge from cracks in the ice, they interact with the oxygen in the atmosphere to make red rust. But something else inside the water was puzzling—it had extremely high concentrations of ocean salts.

Blood Falls.

Why does rust spill out of a relatively tiny patch in the vast Antarctic ice? And why would ultra-briny seawater be emerging from a glacier that sits almost a hundred miles from the nearest ocean?

the Southern Ocean extended deep inside the fiords in this part of Antarctica. Then, starting 5 million years ago, the climate became colder and glaciers encroached into the region. While the sea retreated, a portion of that ancient ocean water got trapped underneath the glacier as it grew. Under Blood Falls lies a fragment of sea that has been isolated from the ocean and sealed under the ice for at least 1 million years.

As ice forms, salts remain in the ancient water that is still in the liquid phase. As more seawater freezes, the liquid water becomes ever brinier.

increasing glacial melt—that is, more warming—will lead to larger numbers of viruses being released that can infect local hosts.

Everywhere we look for viruses in ice, we find them. As the polar regions melt, creatures from the past are exposed to the modern world. In 2014, researchers found thirteen viruses frozen in the ice of Siberian permafrost. Some of them had been trapped in the ice for almost 50,000 years.

In the summer of 2016, temperatures in western Siberia reached nearly 100 degrees Fahrenheit. The warm summers there in recent years have led to the melt of the upper layers of permafrost. Mud and sinkholes are starting to become regular features of the landscape. So, too, is animal disease. That summer, the nomadic peoples in the region noticed that reindeer were dying off in large numbers. By the end of August, more than 2,000 reindeer perished. In addition, 42 local villagers got sick that month and one of them, a twelve-year-old boy, died.

the telltale sign of anthrax infection lay in the blood and respiratory tissues of the victims. Anthrax can survive as bacterial spores that can lie dormant for decades. It is thought that these spores were released as the melting permafrost disgorged a long-dead infected deer from the ice. The deer was a victim of the last anthrax outbreak in the region seventy-five years ago. The spores from the newly exposed carcass then entered the water supply, where it later spread to both reindeer and humans. A plague from the past had reemerged in the warming permafrost.