Being over
10,000km away from the frozen region of Antarctica, the importance of the
Earth’s southernmost continent is often overlooked in the UK. The 1910 race to
the South Pole[1] was
driven by potential claims to new territory, thirst for discovery and knowledge
gain; the latter two are the main reasons we travel to and remain in the
continent to this day. Antarctica has become an international science
laboratory seeing frequent advances in study of climate, oceanology,
meteorology, geology and many other areas.
The continent
was originally split using the sector method by Britain in 1908; this proved
impractical, as subsequently other nations, namely Argentina and Chile, claimed
areas which overlapped with previously distributed land. Conflicts arose until
1957 when, to prepare for the International Geophysical Year, a conference took
place to coordinate Antarctic research[2].
International cooperation was encouraged and many countries were allowed to
establish bases and share resources and scientific information, reducing
geopolitical rivalry. At the end of the IGY, these bases were kept and to this
day over 4000 scientists are simultaneously researching harmoniously on the
continent.
Politically,
Antarctica is unique. It is the only place on Earth with no military presence, as
stated by the Antarctic Treaty System[3].
The system was put into place in 1959 to regulate international relations with
respect to the only continent on Earth without native peoples. The two main
aims were to protect Antarctica’s ecozone and to support scientific research,
making it a continent of peace, environmental protection and science. This is
put into practice by prohibition of military activities, mineral mining,
nuclear explosions and nuclear waste disposal.
Plate Tectonic
Theory professes that that minerals found in the mountains of South America are
likely to match those found in Antarctica as together they once formed part of
Gondwana. As scarcity of natural resources increases, the value of Antarctica’s
rises, thus the incentive to extract them grows. About 50 million years ago
Antarctica was covered by ancient swamps, and in this tie coal was formed along
its coast and throughout the Transantarctic Mountains. Apart from providing
heat for small research stations, it is possible that in the future when coal,
as a non-renewable resource, is depleted in the rest of the world market, Antarctica could become a vital source. Antarctica accounts for 90% of the world’s fresh water;
this has opened many pathways for developing means to a sustainable future:
ideas such as towing icebergs to parts of the world lacking fresh water along
with using Antarctica as a long term deep freeze storage site for food.
Although costs prohibit these particular ideas, this is not to say they are not
achievable in the future.
Small deposits of minerals have been found in
Antarctica[4]. It is
likely that the peninsula contains high quantities of metallic minerals, as do
many other continents that once made up Gondwana, formed by one of three
processes: hydrothermal, magmatic segregation or sedimentation. Uses of the
metals range as much as their economic value, from nuclear fuel (uranium) to
the jewelry industry (platinum). While the Antarctic Treaty has banned
exploitation of Antarctic minerals indefinitely, the future could see
Antarctica as the only viable option as a mineral source, and with development
of more sustainable mining techniques, improving the ease and accessibility of
drilling, it could be that these resources become allowed to be mined in the
future.
Antarctica
plays an integral role in regulating the world’s climate system, and in this
way serves as a global thermostat by way of the albedo effect from the white
ice cover, coupled with the effect on the ocean’s heat budget of the dark sea
surface surrounding the continent. There has been a strong correlation between global
sea level and temperatures in Antarctica over the past 520 000 years[5].
The Earth’s warm ocean currents are driven largely by the sinking of cold
surface water with high salinity in the Southern Ocean. Moreover, the carbon
cycle is affected by the Southern Ocean, which links the physical climate
system to the marine ecosystem. The worldwide ocean food chain’s foundation
depends on phytoplankton, microscopic marine plants which bloom in the Southern
Ocean surrounding Antarctica. These microscopic marine plants thrive in the
nutrient-rich waters and constant summer sunlight of the ocean which accounts
for 10% of the Earth’s surface.
The ocean
absorbs over 40% of the total annual uptake of carbon dioxide from the
atmosphere, although this figure is slowly decreasing[6][7]. The reducing capacity
has been caused by the overall rise in ocean temperature, as warmer water can
take up less carbon dioxide, as well as altered circulation and interactions in
the oceans, ice system and atmosphere. The graph below shows the direct
correlation between carbon dioxide levels and global temperature, proving
fluctuations in one are accompanied by fluctuations in the other.
Antarctica is acknowledged to be one the of the
world’s most vital ‘natural laboratories’. The hole in the ozone layer was
discovered in the 1980s by British Antarctic Survey scientists. Thus Antarctica
is a continent which not only regulates but also indicates the extent of
climate change. The Antarctic Ice sheet system sees ice shelves as a vital
component, which accrete as a result of basal freezing and snowfall. A
convincing piece of evidence for global warming is the break up of the large
Larsen B Ice Shelf in 2002. NASA’s MODIS satellite shows that over 35 days, the
3,250 km2 ice shelf broke. Ice shelf thinning and collapse may be monitored: Satellite
Remote Sensing may record geographic extent (using infrared), thinckness (by
use of laser or RADAR altimetry) and motion (InSAR). Over the past decade,
these methods of data collection brought together provide insight into the huge
extent of thinning of ice shelves around the peninsula, leading to the thinning
of glaciers once connected to them. Thanks to satellite altimetry, we can also
conclude that thinning is taking place even south of the -9oC isotherm. The most likely explanation for
this is basal melting of ice shelves is ocean warming. When shelves collapse,
this has a regional effect on the ice feeding the shelf system: glacial systems
are buttressed by the ice shelves they feed and without they see rapid
increases in velocity. Until new buoyancy thresholds are established, the
glacier will pass topographic obstacles which partially stabilise it but cause
sudden changes in friction. This process has been recorded by satellites
viewing the periphery of the former Larsen B embayment.[8]
Research into understanding ice-aerosol layers in the
Earth’s atmosphere is crucial to identifying the effects of global climate
change. In the summer of 2008, by use of complex radar and lidar instruments
(for ground-based measurements) and AIM satellite, five scientists observed the
first Southern Hemisphere study of noctilucent clouds. These clouds only appear
in the polar regions in the summer and form at about 85km high in the
mesosphere at temperatures below -120ºC, but are a sensitive indicator of
climate in the middle atmosphere. Greater occurance and coverage of noctilucent
clouds (as observed in the Northern Hemisphere) will help to verify the climate
models which predict a cooling of the mesosphere.[9]
Furthermore, cylindrical sections of ice called ice cores are drilled from
ice sheets in Antarctica. They represent 800 000 years of snow accumulation and
each acts as a time capsule with information about the atmosphere at the time
of snowfall. Precise evidence can be obtained from ice cores in a number of
forms: air temperature from the stable isotope ratios of oxygen to hydrogen, quantity
of snowfall from the thickness of annual layers and extent of wind erosion and
levels of vegetation from dust concentration. Even major volcanic eruptions can
be identified by the tephra shards and acidity levels of the ice.
Home to the Southern Hole
(providing a view into the very early universe), Antarctica’s reputation as “a
continent dedicated to science”[10]
can be attributed to its laws against destructive uses and the vast opportunity
it provides for research. The continent attracts astronomers: radiation at
miniscule, submillimeter wavelengths can be observed due to the absence of
water vapour and thin atmosphere above the continent. The low air pressure also
reduces noise from the atmosphere and wind is reduced by the extremely low
temperatures. As
well as scientific research, tourism in Antarctica began with sea tourism in
the 1960s. During the tourist season of 2009-2010, over 37,000 people visited
the continent[11].
This is a dangerously high number of people to be visiting such a fragile
environment, and if the tourist industry is to continue expanding, it will have
to be regulated because the unique environment of Antarctica matters and should
not be deteriorated.
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