In the furthest, most frigid region of our planet’s southern hemisphere, sprawls the highest, coldest, driest, and most isolated place on earth. Antarctica is a vast land of mountains, ice, tundra, and extreme, inhospitable cold that has kept it relatively unexplored and uninhabited even nearly 200 years after its initial discovery. Yet as technology improves and humankind’s ever growing desire to push at the boundaries of our understanding of our planet propels us forward, we are just starting to scratch at the surface of Antarctica’s myriad mysteries. What we are finding is that Earth’s most remote and extreme continent is even stranger than we had ever thought.
Antarctica covers an area of 14.0 million km2 (5.4 million sq. mi), which is roughly twice the size of Australia or one and a half times the size of the United States, making it the fifth largest continent in the world. Although it is 98% covered with ice, which is well over a mile thick in most places, Antarctica is considered to be one of the driest places on earth, with only 200 mm (8 inches) of annual precipitation along its coast and even less inland. The cold in this wind-blasted land is staggering, with recorded temperatures reaching a deadly −89 °C (−129 °F). For this reason, human habitation of the continent is limited, and there are no permanent settlements. For the most part, the extent of human habitation consists of research stations representing many countries found peppered throughout the continent and engaged in various scientific pursuits.
For such a large landmass Antarctica long remained a mere myth, a lost land that was once known as Terra Australis Incognita, or the “Unknown Southern Land,” the existence of which for a long time remained almost a legendary quest and the doom of many failed expeditions to locate it. Although speculation and legends of its existence go far back, and there were discoveries of some of its satellite icebergs and islands, the Antarctic mainland was not really properly discovered until 1820, when a continental ice shelf was spotted by a Russian expedition led by Fabian Gottlieb von Bellingshausen and Mikhail Lazarev aboard the Vostok and Mirny. Even upon this discovery, the icy continent remained mostly neglected and forgotten at the bottom of the world since no one was willing to brave the extremely hostile conditions of this uncharted, extreme wilderness. It wasn’t until 1911 that the first human beings successfully penetrated the interior of Antarctica, when Norwegian explorer Roald Amundsen and four other expedition members became the first to reach the South Pole after a perilous overland journey.
In the ensuing century, Antarctica largely remained an unexplored, poorly understood realm of cold and ice, and it has only been recently that improving technology and satellite imagery have helped us to really start scratching the surface of its frigid mysteries. Even so, Antarctica’s mysteries run deep, and what we are uncovering here at the very bottom of the world is mostly posing more questions than answers. As we look deeper into the ice and probe more thoroughly at the edges of what we know about this hostile and perilous place, Antarctica is proving to be much more than the enormous chunk of ice it was once thought to be.
Some of the most exciting discoveries in Antarctica are related to its very composition. The continent is well understood to be mostly comprised of ice, specifically two massive continental ice shelves that cover nearly 99% of Antarctica’s area and reach to nearly 3 miles deep in some of the thicker spots. There is so much ice here that it is estimated to hold around 90% of the world’s freshwater ice. That’s a lot of ice, and for a long time it was thought that that was all there was to it. Indeed that was what most scientific research in Antarctica was focused on, the composition and depth of the ice here. However, in 1958, a Soviet expedition measuring the thickness of the ice across the eastern half of the continent stumbled across a discovery that challenged the previous notions of Antarctica as basically solid ice. The expedition had been trekking overland over a 2 mile thick ice sheet and detonating explosives every 100 miles to gage ice thickness when they found that the ice in the center of the sheet, which should have been miles deep, was actually much thinner than anticipated. Further investigation showed that the scientists had stumbled across a sprawling range of mountains hidden away beneath the ice in terrain that was otherwise completely flat. These were no minor peaks or hills either. Later called the Gamburtsev Mountains, the craggy slopes reached heights of 9,000 feet (3,000 meters) and meandered for 750 miles (1,200 km) into the interior.
What makes these ice ensconced mountains even more bizarre is the fact that they are even there at all. It is estimated that the Gamburtsev Mountains are around 900 million to a billion years old, enough geological time for most mountains to have eroded away to nothing. Yet these mountains are still there in all of their magnificence, hidden from view under vast amounts of ice. It is thought that some poorly understood geological process transformed the density of the mountains’ roots, essentially making them more resistant to the natural forces that would have been perpetually conspiring to wear them down to nubs. How this has happened remains a mystery and the mountains’ very existence has scientists scratching their heads.
Mountains under the ice are not the only peculiar geological oddity to be found in Antarctica. Although the continent is largely thought of as being nothing but ice and snow, it is also home to one of the world’s most extreme deserts. In a place known as the McMurdo Dry Valleys there is practically no ice to be found at all, and bare, wind scorched bedrock and gravel stretches as far as the eye can see. This peculiar anomaly in a land more than 98% covered in ice is caused by a combination of several unique natural forces. First of all, the mountains surrounding the valleys work to prevent the ice sheet from moving in and covering the area. In addition, fierce, 200mph katabatic winds crash down from the mountains, building heat as they rush to the valley floor and evaporating all moisture in their path, which leaves the valley devoid of any snow, ice, or humidity. The overall effect is a bizarre, otherworldly land of frigid naked rock in a realm otherwise almost entirely covered in blinding white snow and ice. The McMurdo Dry Valleys cover around 0.3% of Antarctica’s total land area, making them the largest ice free region here, and they also happen to hold the continent’s longest river, the Onyx River. The Dry Valleys were designated as an environmentally protected area in 2004
There are other oddities to be found in Antarctica as well. Among the sub glacial Gamburtsev Mountains, near Russia’s Vostok Station and lying beneath a staggering 4,000 m (13,100 ft) of solid ice is an enormous lake of liquid water known as Lake Vostok. At 250 km (160 mi) long by 50 km (30 mi) wide, and sprawling over an area of 12,500 km2 (4,830 sq mi), with an average depth of 432 m (1,417 ft), it is by far the largest of Antarctica’s over 200 documented subglacial lakes. Lakes such as Lake Vostok come into existence when heat from the Earth’s core melts the ice at the bottom of an ice sheet and the top of the ice sheet acts as a sort of insulation. Geothermal heat works to keep the lake water from freezing solid and keeps the water temperature at around 27 degrees Fahrenheit (minus 3 degrees Celsius). It is certainly not a place to take a dip, but the fact that a liquid lake could exist at all under miles of ice is mind boggling.
Lake Vostok was first suspected to exist during seismic surveys by Soviet expeditions mounted in 1959 and 1964, and its existence was confirmed in 1996 by airborne radar experiments carried out by British and Russian researchers. It was not until 2012 that researchers were able to finally penetrate deep enough to pierce the ice shield of the lake, which consequently sent lake water erupting forth through the borehole. The ice core was the longest ever attempted, at 3,768 m (12,400 ft). Samples of freshly frozen lake water in Lake Vostok’s frozen upper layer were taken in 2013 by a Russian team which plans to send a submersible probe into the lake’s liquid layer.
Perhaps just as strange as the existence of a lake the size of Lake Ontario under the Antarctic ice or swaths of land bare of ice in an ice covered realm is the presence of life in these most unlikely of places. In Lake Vostok, getting samples of actual liquid lake water has proven to be a monumental task, and the first such samples were not obtained until 2013. Although the samples have not been thoroughly analyzed yet, there is plenty of evidence that Lake Vostok could support a myriad of lifeforms, far from the sterile, barren environment its location would seem to suggest. DNA samples that were retrieved from frozen lake water scraped from ice buildup over the surface and from glaciers sliding over it suggested a staggering array of life for such a hostile environment. Of the over 3,500 different DNA sequences retrieved from these samples, it was found that in addition to bacteria and eukaryotes, some sequences closely matched more complex organisms such as mollusks, water fleas, and arthropods. The discovery of the presence of microbial life in Lake Vostok would not be unprecedented as such lifeforms were confirmed to exist in another subglacial lake, Lake Whillans, in 2013.
To make things even more exciting, some of the bacteria found were characteristic of the type that live in fish guts, suggesting that some unknown species of fish could be lurking in the depths of the lake, which has proven to be a highly controversial idea in the scientific community to be sure. Since some of the sequences have hallmarks of deep sea thermal vent organisms, it is believed that there could be similar hydrothermal vents beneath Lake Vostok that support a whole ecosystem of never before seen lifeforms. A ridge separating two sections of the lake seems to support this theory as it appears it could be a vent system. Considering Lake Vostok has been under the ice completely isolated from the world for 15 to 25 million years, there is the potential for a variety of extremely unique biological discoveries. Any life found in this most extreme of habitats would be promising for the potential discovery of similar life outside of our planet, such as in the icy seas of Jupiter’s moon Europa.
The McMurdo Dry Valleys, which seem to be as close to the surface of another planet as we can get on Earth, have also shown to harbor tenacious lifeforms that are like no other on earth. Photosynthetic bacteria have been found to live in the moist interior of rocks and getting soil nutrients from summer meltwater from glaciers. Water samples from a place in the McMurdo Dry Valleys known as Blood Falls due to its uniquely red tinted water from high levels of iron dioxide have also turned up the exciting discovery of bacteria that exhibit metabolic processes that are totally unique and never seen before. These bizarre bacteria are anaerobic, with a unique metabolism based on iron and sulfur. The types of life found here have challenged previously held notions of the conditions that life is able to adapt to, and the area draws researchers from all over the world, who keep a base of operations nearby known as McMurdo Station.
Even the ice itself in Antarctica has posed some intriguing biological discoveries. Bacteria have been found to live in tiny veins of liquid water in the ice sheets themselves, squeezing out whatever nutrients they can. It is unclear if these bacteria actually represent a working ecosystem or are in some sort of state of suspended animation, but they have shown some pretty unique qualities. In one case, dormant ancient bacteria estimated as being around 420,000 years old was pulled up from ice nearly 2 miles under the sheet, yet when the water was melted the bacteria sprang to life and began to grow. It remains to be seen just how active an ecosystem these extraordinary bacteria have.
The possibilities of more biological discoveries extends out into the frozen seas of Antarctica as well. The continent’s surrounding waters are home to a plethora of uniquely cold adapted organisms from fish with built in antifreeze to leggy sea spiders the size of dinner plates to tiny waterborne organisms found nowhere else, and it has long baffled biologists as to how such an extreme environment can be so teeming with such a wide array of life. One of the great frontiers of biological intrigue within Antarctica is the mystery of what we might find living under the virtually unexplored ocean below the ice sheets surrounding the continent. Ice shelves such as the Ross Ice Shelf, at 197,000 square miles (510,680 square km) in area, can be absolutely gargantuan. Very little to nothing is known of what kind of life exists under these impenetrable realms of ice, glaciers and icebergs. These frigid, ice-ringed seas are a vast mystery that we have only just begun to poke at, and there are truly more remarkable extreme lifeforms and ecosystems yet to be found living here.
Perhaps the biggest mystery of all is why Antarctica is experiencing major upheavals in terms of its ice composition in modern times. It is becoming more and more apparent due to ongoing research that the Antarctic ice shelves are far more vulnerable and a much bigger source of global sea level rises than anyone ever thought possible. Up until around the 1980s, Antarctica was not seen as a significant player in global climate change, as it was thought that the sheer enormity of the ice sheets would make it impossible for climate changes to have any significant impact, however, ongoing research has painted a different picture. It has been found in the past couple of decades that the Antarctic ice sheets lie on shifting, malleable sediments that allow the glaciers to slide smoothly along their paths, and that large portions of the sheets lie well below sea level, both of which point to a far more vulnerable environment than was ever suspected before.
It has been observed that the ice sheets, particularly the West Antarctic Ice Sheet, are undergoing rapid changes of an unprecedented magnitude. The seemingly unstoppable plains of thick ice are losing mass at an amazing rate. Scientists are observing changes that should have taken a century occur over the course of a decade and no one is really quite sure why as it is hard to peer under these vast expanses of solid ice. What is known is that the effects on the rest of the world could be considerable. If, for instance, the aforementioned West Antarctic Ice Sheet were to melt completely, world sea levels would rise by an estimated 16 feet (5 meters). That is enough to erase a whole lot of beach front property and completely obliterate some island nations from the face of the earth.
It is clear that the land at the bottom of our planet is a lot more than a big, barren wasteland of ice. Thousands of scientists from a myriad of countries continue to utilize ever growing technologies to try and understand this last mysterious frontier of the natural world. Antarctica is truly a majestic and mysterious domain that encompasses deep enigmas both geological and biological. Here we are learning about the very extreme limits of what life is capable of enduring and finding models on which to base speculation of possible life on far away inhospitable worlds. There are so many discoveries awaiting the many scientists from all over the world who brave the snow and wind blasted terrain of this alien realm, but they may be running out of time. It is somewhat sad to think that large portions of this frozen, enigmatic land so brimming with potential discovery could dwindle away before we ever really truly understand it.