The prospect of mining in and around Antarctica really came to public attention in the 1970s, after the international oil crisis. In the late 1980s the Convention on the Regulation of Antarctic Mineral Resource Activities (CRAMRA) was adopted as part of the Antarctic Treaty System as a precautionary attempt to put rules in place in case the region did become accessible to commercial mining. However, this action was opposed from various angles. Environmental groups such as Greenpeace protested against the potential despoliation of the wilderness, asking instead for World Park status. Developing nations – particularly Malaysia – voiced concerns that the region would be divided up by richer nations, and suggested that Antarctica be managed instead by the United Nations.35 This controversy meant that Australia and France refused to sign the Convention; other nations soon joined them. The result was the Protocol on Environmental Protection to the Antarctic Treaty or ‘Madrid Protocol’, mentioned earlier. Signed in 1991 and entering into force in 1998, the Protocol included, among other things, an indefinite ban on mining (the Protocol can be reviewed in 2048).
Another form of ‘mining’ has been happening in Antarctica for decades. ‘Bioprospecting’ – searching for naturally occurring biological substances that can be used for health or other benefits – has obvious potential in Antarctica, where the extreme environment produces organisms with unusual capabilities. A prominent example is the antifreeze glycoproteins produced by the group of fish called notothenioids (such as the Antarctic toothfish). First discovered in the late 1960s, these biological agents prevent the fishes’ body fluids forming ice crystals in sub-zero temperatures. They could have a range of applications, from preserving tissues more effectively during transplant surgery to prolonging the shelf-life of frozen food. It is not just the continent’s rich surrounding waters at stake here, however; the ice itself and subglacial lakes can also be home to ‘extremophiles’, and present potentially useful – and lucrative – resources for bioprospectors. However, the activity, enabled by scientists supported by national programmes in a continent that is still unowned, raises many legal, ethical, commercial and environmental issues, which are currently being debated by Antarctic Treaty nations.
A far more high-profile threat to Antarctica’s current environment is global warming. The continent is playing a crucial part in climate change science and political debate, in several senses: as a tool for understanding climate variation; as a region that may be severely affected by warming temperatures; and as the possible source of disastrous impact on the rest of the globe, should its ice sheets become unstable. The ice sheets store millions of years’ worth of climate data that, retrieved in the form of ice cores, demonstrates the connection between increased atmospheric carbon dioxide and temperature, and provides a background of natural variation against which current changes can be compared.36
This satellite image of the Larsen B Ice Shelf from early 2000 shows pools of meltwater and icebergs splintering off. The shelf collapsed in 2002.
The impact of anthropogenic climate change on the region is more complex: while East Antarctica is thus far little affected, the waters around the continent and West Antarctica – particularly the Antarctic Peninsula – are warming. Spectacularly, several large ice shelves have broken off the Peninsula. In 2002 the enormous Larsen B shelf, having stayed stable since the last ice age, collapsed – an event scientists believe is related to anthropogenic changes to atmospheric circulation.37 The West Antarctic ice sheet is increasingly losing mass due largely to the interaction between the warmer ocean and its marine glaciers.38 The potential impact of a melting Antarctica is catastrophic. The continent contains ten times more ice than the rest of the Earth put together: an increase in temperature of several degrees could cause the collapse of the whole West Antarctic ice sheet, producing a sea level rise of about 1.5 m (5 ft).39 If the much larger East Antarctica sheet were eventually also to collapse, the net rise would be around 58 m (190 ft). It is the grounded ice that would produce this rise, as opposed to ice that already displaces water, such as floating ice and ice below sea level.40
Where does this leave the Geographic South Pole? Neither high nor dry, if all the Antarctic ice were to melt. This worst case scenario is not likely in the foreseeable future, but climate models show that future temperature changes will be amplified on the Antarctic plateau, about 20 per cent higher than average. The South Pole would be several degrees warmer – a scenario that has occurred before in interglacial periods, with a corresponding sea-level rise.41 The poles – defined as the points where the planet’s axis meets its surface – will shift as a result of this melting: redistribution of water can change the location of the planet’s rotational axis. Research has shown that the North Pole, drifting on average southwards along the 70 degrees west meridian over the last century or so, has recently made a lurch to the east, most likely due to increased rates of melting ice.42 The South Pole, it stands to reason, must have made its own shift. Only a century ago, humans had barely reached the poles; now, it seems, we have inadvertently managed to move them.
An image of Earth in September 2005 with the entire Antarctic region visible.
7 Looking Up and Looking Down
The South Pole’s unusual combination of physical features gives it peculiar advantages as a site for scientific investigation. However, the science that takes place at the South Pole is not necessarily about the place itself. There is no wildlife to observe there, no trees or flowers to study, no exposed rock to examine. Instead, the Pole is an excellent place to look from, whether this is up into space or down into the ice – or into the core of the Earth. Research that seems very local can have global – even cosmic – significance.
Not just the Pole but the whole polar plateau offers itself as a site for research. The plateau’s physical extremes – its status as the highest, driest, coldest, most isolated and, for some months of the year, darkest region on Earth – bring unique scientific advantages. There are, admittedly, specific benefits for some experiments in being on the Earth’s rotation axis (the Pole itself). For much scientific work, however, there are many places on the plateau, including other stations, that are as good as or better than 90 degrees south, judged purely on environmental conditions. The Pole’s advantage – ironically, for the ‘last’ place on Earth – is its comparative accessibility and pre-existing infrastructure. Heavy equipment can be flown in and out by U.S. military aircraft or hauled across the ice on motorized vehicles along a pre-smoothed ‘road’. Scientific and support personnel in the hundreds can be accommodated in the station and nearby ‘summer camp’.
A wide variety of scientific experiments take place at the South Pole. Its clean air, which is free from most of the usual local pollutants, is used to determine wide-scale changes to atmospheric composition; levels of carbon dioxide and ozone have been continually monitored for around 50 years. In its long winter darkness, auroras are studied for what they can tell us about space weather (the environmental conditions of the region of space near Earth). NASA uses the interior of Antarctica as an analogue for the terrain and temperatures of Earth’s neighbouring planet Mars. Even scientists themselves become subjects of study by psychologists interested in the dynamics of isolated groups. However, the South Polar science that attracts most attention – and costs the most money – involves examining data found in the sky above or the ice below.
Antarctica provides the world’s best conditions for astronomical research. While some forms of astrophysics can be conducted from coastal bases such as McMurdo and Mawson stations, it is the plateau that offers astronomers ‘the best seeing conditions, the darkest skies and the most transparent atmosphere’.1 The plateau’s primary attraction for astronomers (who use numerous techniques, including optical, radio and infrared telescopes) is its high, cold, dry and isolated location. For telescopes looking at the microwave and infrared radiation arriving from deep space, the dry air is paramount. Water vapour absorbs and re-emits the radiation, interfering with the data. Both t
he height of the plateau and the cold temperature reduce water vapour significantly. In addition, the dryer the atmosphere, the more uniform it is; the ‘noise’ of local fluctuations is reduced.2 The isolation means that anthropogenic disturbances such as aerosols, aircraft contrails and light pollution are minimized.
Unoccupied, snow-covered Jamesway huts wait for the summer station population to arrive.
NASA’s robot explorer ‘Tumbleweed’, a prototype of a device that could be used to look for water on the Martian icescape, was released at the Pole in 2004, making a 70-km (43-mile) journey over the plateau.
The Pole itself (as opposed to the plateau more generally) has both pros and cons as an astronomical site. The six months of darkness mean that problematic diurnal temperature changes are absent; moreover, if your telescope is at the Earth’s axis of rotation, it has continuous access to the same area of sky.3 Visible objects stay at the same elevation, rather than rising and setting, meaning that the amount of atmosphere you look through stays constant, resulting in more stable observations. However, located on the slope rather than the centre of the plateau, the Pole is lower than some other possible plateau sites, slightly windier (creating less stable air conditions near the surface), cloudier and more subject to interference from auroral activity.4 Dome A is probably the best of the occupied inland sites for astronomical projects, with Dome F also very favourable, and the presently uninhabited Ridge A (running southwest from Dome A) the best site of all.5 However, while several plateau stations do include astronomical research – such as the PLATeau Observatory (PLATO) at Dome A, robotically controlled to run year-round – the station facilities and the ability to fly large amounts of equipment in mean that the primary site of Antarctic astronomy and astrophysics has been the South Pole.6
The South Pole Telescope at twilight, 2012.
Astronomical research at the South Pole began in 1979 with observations of the sun over a long continuous period, and really took off in the early 1990s with the construction of the Martin A. Pomerantz Observatory (MAPO), named after the scientist who had led many of the early experiments.7 Like other instruments used by astronomers and astrophysicists, this observatory sits in the ‘Dark Sector’, located across the compact-snow skiway from the station, where light and radio pollution are kept to a minimum. While a range of projects are under way at any one time, the investigation of the Cosmic Microwave Background Radiation (CMBR) has been particularly prominent. CMBR is the background ‘glow’ left over from the explosion that began the universe, the ‘Big Bang’; it is strongest in the microwave section of the electromagnetic spectrum. While this radiation is largely uniform, small variations provide information about the early universe and hence about its current structure. Observations of stellar explosions have shown that the universe is expanding at an accelerating rate, despite the opposing force of gravity, suggesting the existence of another mysterious entity, dubbed ‘Dark Energy’. This phenomenon, among others, is investigated using the South Pole Telescope (SPT), a 10-m (33-ft) radio telescope that sits white and strangely beautiful against the horizon. Built at a cost of more than $19 million, the SPT began collecting data in 2007. A neighbouring telescope, BICEP2, has made major contributions to understanding the universe’s beginning: in 2014 it identified the influence on the CMBR of gravitational waves that occurred in an unimaginably small instant following the Big Bang. This in turn confirmed the theory that the very early universe experienced a period of ‘inflation’, or exponentially accelerating expansion. This data could also shed light on the fundamental issue of how quantum physics and relativity are connected.8 The South Pole, the symbolic ‘last place’, may have provided an important step in the search for a ‘Theory of Everything’.
A flagline in the ‘Dark Sector’ helps people to find their way during the long Antarctic night. The South Pole Telescope can just be seen on the horizon.
A closer shot of the South Pole Telescope (SPT), with some new additions, in 2013.
Less visible than the SPT but equally high-profile is the experiment buried within the ice: the IceCube Neutrino Observatory. Costing USD$279 million, IceCube began operating in 2010. Where the SPT takes advantage of the height of the plateau to look up at the stars, IceCube exploits the depth of the ice, using it as a giant telescope to watch for elusive particles. These are tiny, almost massless neutrinos, which travel very close to the speed of light. Neutrinos are another key to understanding the structure and evolution of the universe. If a neutrino collides with other particles, this event can be detected from the light it produces. However, because the particles are so small and uncharged, these interactions are very rare: if the detecting area were human-sized, it would take around 100 years for an event to occur – 100,000 years in the energy range that IceCube can detect. The larger the detector, the more often you will see an interaction; IceCube uses a cubic kilometre of ice. More than 5,000 detectors are buried between 1,450 and 2,450 m (4,760 and 8,040 ft) below the surface of the plateau, attached to cables placed in 86 holes made using hot-water drills. The darkness and clearness of the ice is ideal for detection: IceCube observes about 275 neutrinos every day. And although the ice moves 10 metres per year, it moves in one piece, so the experiment remains intact.9 As with the SPT, the immense size of the project, along with the enigmatic nature of the particles it is designed to observe, creates a cachet that is reinforced by its glamorously remote South Polar location.
Another group of scientists who look down from the South Pole are seismologists. The South Pole is an excellent place to study earthquakes, but not because Antarctica is particularly prone to this phenomenon. On the contrary, it suffers the least number of tremors of any continent. Again, this is a case of science using the South Pole to look elsewhere: its position at the spin axis means that the Earth’s rotational forces do not affect measurements as they do in other places, so seismic events elsewhere in the planet can be observed with an unusual clarity. The North Pole also has this advantage, but there is no Arctic continent to which recording equipment might be secured.10
The most recent seismological station – one of a global cooperative network – is housed in the South Pole Remote Earth Science Observatory (SPRESO), located in the Quiet Sector, 8 km (5 miles) away from the main station building, where vibrations and noise produced by equipment and vehicles are kept to a minimum. To achieve even less interference, seismometers have been buried 300 m (1,000 ft) down into the ice. As a result, they can record ‘the quietest vibrations on Earth, up to 4 times quieter than ever before observed’.11 This means that SPRESO can detect seismic activity that has propagated through the Earth from distant regions of the globe, gathering data about the planet’s internal structure. As the science writer Gabrielle Walker explains, the observatory ‘could act as a sort of inward telescope, constructing an image of the Earth’s mantle of rock, its liquid outer core made of almost pure iron, and the hot hard solid sphere of iron that lies at the centre of the Earth’.12 Studies of seismic activities were a crucial part of the original station’s programme in the late 1950s, and now form the longest-running of any scientific data set at the Pole. They provide evidence that the Earth’s solid core spins more quickly than the rest of the planet.13 And SPRESO can also detect anthropogenic disturbances to the planet: it acts as a monitoring station for the Comprehensive Nuclear-Test-Ban Treaty. The very lack of activity – lack of spin, lack of noise – means that it is a unique place from which to listen to the hustle and bustle of the rest of the globe.
Scientists seem to be drilling enough holes at the Pole at present to satisfy even John Cleves Symmes Jr. Where the Ice-Cube physicists bury their neutrino detectors deep in the ice to create a giant telescope, and the seismologists of SPRESO lodge their detectors hundreds of metres down to escape extraneous noise, glaciologists drill down to examine the ice itself – or rather, the atmospheric traces it contains. Retrieving and analysing ice cores is one of the most urgent and important scientific activities in Antarctica. An
ice core is a continuous vertical sample drilled from an ice sheet or glacier, stored in cylindrical sections about a couple of metres long. These are, in a sense, solidified representations of time. Analysis of materials in the ice, including dust, volcanic ash and trapped gas, provides information about the Earth’s environment over past periods, such as temperature and levels of carbon dioxide – something of vital importance to understanding and contextualizing current changes in climate.
In any one place, if there has not been significant faulting or folding, the deeper the ice from which the core is retrieved, the longer ago it was deposited. However, the varied rate of snow accumulation in the Antarctic interior means that the equation between depth and time changes from place to place. High up on the plateau, the snow accumulation is very low, with the result that the kilometres of ice offer a very long record. Vostok Station is well situated for examining long-term climate variation through ice cores. A 150,000-year, 2-kilometre core recovered in the late 1980s, followed by a 420,000-year, 3.3-kilometre core in 1996, provided important data showing the link between temperature and carbon dioxide in the atmosphere.14 Along with other ice cores, such as the 800,000-year, 2.8-kilometre sample recovered at Dome C, they offer a record of natural variation against which current changes can be compared, establishing evidence for anthropogenic climate change.
At the South Pole, snow accumulation is significantly faster than at Vostok, and the ice is correspondingly younger; records are thus shorter but finer in their detail.15 The South Pole Ice Core project (with the appealing acronym SPICE) aims to retrieve a 1,500 metre ice-core, representing about 40,000 years – not much in terms of time compared to the core recovered at Dome C. Its resolution, however, is expected to be the highest of any East Antarctic core.16 The movement of the ice is another factor: the South Pole core ‘should offer relatively well-ordered stratigraphy, meaning the layers are well defined and the youngest layers are on top and the oldest layers are on the bottom, with no evidence of folding or faulting in between’. As with much South Polar science, however, the ‘logistical support’ already available at the station is a strong factor in the location of the experiment.17
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