Antarctica is a unique continent in that it does not have a native human population. Recently, yet again a vast iceberg the size of greater London broke off the Antarctic ice shelf due to the natural process of calving. But the Antarctic ice sheets have been melting and breaking away due to climate change. Read here to learn more about the concerns related to Antarctica.
Antarctica is the fifth-largest continent in terms of total area as it is larger than both Oceania and Europe. Antarctica is a unique continent in that it does not have a native human population.
There are no countries in Antarctica, although seven nations claim different parts of it: New Zealand, Australia, France, Norway, the United Kingdom, Chile, and Argentina.
Despite its size and harsh environment, Antarctica is vulnerable to damage from human activities.
The Continent of Antarctica
The continent of Antarctica makes up most of the Antarctic region. The Antarctic is a cold, remote area in the Southern Hemisphere encompassed by the Antarctic Convergence.
- The Antarctic Convergence is an uneven line of latitude where cold, northward-flowing Antarctic waters meet the warmer waters of the world’s oceans.
- The Antarctic covers approximately 20 percent of the Southern Hemisphere.
The Antarctic also includes island territories within the Antarctic Convergence. The islands of the Antarctic region are:
- The South Orkney Islands, South Shetland Islands, South Georgia, and the South Sandwich Islands, all claimed by the United Kingdom;
- Peter I Island and Bouvet Island, claimed by Norway;
- Heard and McDonald Islands, claimed by Australia;
- Scott Island and the Balleny Islands, claimed by New Zealand.
Also read: Solstice and Equinox
Physical geography
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The Antarctic Ice Sheet is the largest single piece of ice on Earth. The ice surface dramatically grows in size from about three million square kilometers (1.2 million square miles) at the end of summer to about 19 million square kilometers (7.3 million square miles) by winter.
Antarctica has several mountain summits, including the Transantarctic Mountains, which divide the continent into eastern and western regions.
Without any ice, Antarctica would emerge as a giant peninsula and archipelago of mountainous islands, known as Lesser Antarctica, and a single large landmass about the size of Australia, known as Greater Antarctica.
- Greater Antarctica, or East Antarctica, is composed of older, igneous and metamorphic rocks.
- Lesser Antarctica, or West Antarctica, is made up of younger, volcanic and sedimentary rock. It is part of the Ring of Fire around the Pacific Ocean.
- Mount Erebus, located on Antarctica’s Ross Island, is the southernmost active volcano on Earth.
Climate and Waters
Antarctica has an extremely cold, dry climate.
- Winter temperatures along Antarctica’s coast generally range from -10° to -30°C (14° to -22°F).
- During the summer, coastal areas hover around 0°C (32°F) but can reach temperatures as high as 9°C (48°F).
The Antarctic region has an important role in global climate processes. It is an integral part of Earth’s heat balance.
- Ice is more reflective than land or water surfaces. The massive Antarctic Ice Sheet reflects a large amount of solar radiation away from the Earth’s surface.
- As global ice cover (ice sheets and glaciers) decreases, the reflectivity of Earth’s surface also decreases.
- This allows more incoming solar radiation to be absorbed by Earth’s surface, causing an unequal heat balance linked to global warming, the current period of climate change.
The waters surrounding Antarctica are a key part of the “ocean conveyor belt,” a global system in which water circulates the globe based on density and currents.
- The cold waters surrounding Antarctica, known as the Antarctic Bottom Water, are so dense that they push against the ocean floor.
- The Antarctic Bottom Water causes warmer waters to rise, or upwell.
- Antarctic upwelling is so strong that it helps move water around the entire planet. This movement is aided by strong winds that circumnavigate Antarctica. Without the aid of the oceans around Antarctica, Earth’s waters would not circulate in a balanced and efficient manner.
The Antarctic Ocean was officially recognized as the Southern Ocean by the National Geographic Society in 2021.
Flora and fauna
Lichens, mosses, and terrestrial algae are among the few species of vegetation that grow in Antarctica. More of this vegetation grows in the northern and coastal regions of Antarctica, while the interior has little if any vegetation.
The waters surrounding Antarctica are among the most diverse on the planet. Upwelling allows phytoplankton and algae to flourish.
- Thousands of species, such as krill, feed on the plankton. Fish and a large variety of marine mammals thrive in the cold Antarctic waters.
- Blue (Balaenoptera musculus), fin (Balaenoptera physalus), humpback (Megaptera novaeangliae), right, minke, sei (Balaenoptera borealis), and sperm whales (Physeter macrocephalus) have healthy populations in Antarctica.
- One of the top predators in Antarctica is the leopard seal (Hydrurga leptonyx). The leopard seal is one of the most aggressive of all marine predators.
- The most familiar animal of Antarctica is probably the penguin. They have adapted to the cold, coastal waters.
The political history of Antarctica
For many European and North American powers, Antarctica represented the last great frontier for human exploration. Supported by advances in science and navigation, many explorers took on the “Race for the Antarctic”.
- By the early 20th century, explorers started to traverse the interior of Antarctica. The aim of these expeditions was often more competitive than scientific. Explorers wanted to win the “Race to the South Pole” more than understand Antarctica’s environment.
- Because early explorers confronted extreme obstacles and debilitating conditions, this period became known as the “Heroic Age”.
The second half of the 20th century was a time of change initially fueled by the Cold War, a period defined by the division between the United States and the Soviet Union, and the threat of nuclear war.
The International Geophysical Year (IGY) of 1957-58 aimed to end Cold War divisions among the scientific community by promoting global scientific exchange.
- The IGY prompted an intense period of scientific research in the Antarctic. Many countries conducted their first Antarctic explorations and constructed the first research stations in Antarctica.
To prevent conflict over Antarctica, an international treaty governing the usage of the continent was negotiated by a dozen nations, including the United States, the Soviet Union, and other major powers.
- The Antarctic Treaty was agreed upon in 1959 and entered into force in 1961. Today, 47 nations have signed the treaty.
- The treaty established that ‘the region south of 60°S latitude remain politically neutral; no nation or group of people can claim any part of the Antarctic as territory; countries cannot use the region for military purposes or to dispose of radioactive waste, and research can only be done for peaceful purposes.’
- The Antarctic Treaty was an important geopolitical milestone because it was the first arms control agreement established during the Cold War.
The Antarctic Treaty does support territorial claims made before 1961, by New Zealand, Australia, France, Norway, the United Kingdom, Chile, and Argentina. Under the treaty, the size of these claims cannot be changed and new claims cannot be made.
Research in Antarctica
While the Antarctic does not have permanent human residents, the region is a busy outpost for a variety of research scientists.
- These scientists work at government-supported research stations and come from dozens of different countries.
- The number of scientists conducting research varies throughout the year, from about 1,000 in winter to around 5,000 in summer.
- The exploration of Antarctica began in the early 1800s.
- In 1984, a meteorite from Mars was found in Antarctica. The markings on this meteorite were similar to markings left by bacteria on Earth.
Researchers from a variety of scientific backgrounds study the Antarctic not only as a unique environment but also as an indicator of broader global processes.
- Geographers map the surface of the world’s coldest and most isolated continent.
- Meteorologists study climate patterns, including the “ozone hole” that opens over the Antarctic.
- Climatologists track the history of Earth’s climate using ice cores from Antarctica’s pristine ice sheet.
- Marine biologists study the behavior of marine fauna especially whales, seals, and squid.
- Astronomers make observations from Antarctica’s interior because it offers the clearest view of space from Earth.
- Even astrobiologists, who study the possibility of life outside Earth’s atmosphere, study materials found in the Antarctic.
Indian Antarctic Programme
The National Centre for Polar and Ocean Research (NCPOR), inside the Ministry of Earth Sciences of India, is in charge of the multidisciplinary Indian Antarctic Programme.
The first Indian expedition to Antarctica was in 1981.
- The initiative acquired acceptability on a global scale after India signed the Antarctic Treaty in 1983 and built the Dakshin Gangotri Antarctic research outpost, which was replaced by the Maitri site in 1989.
- Bharati, a base made of 134 shipping containers, was the most recent one to be put into service in 2012.
- India, which has made 40 scientific excursions to the Antarctic, is studying atmospheric, biological, earth, chemical, and medicinal sciences as part of the program.
Read here: Indian Antarctic Bill 2022
Future concerns
Two important and related issues that concern the Antarctic region are climate change and tourism.
Antarctic tourism has grown substantially in the last decade.
- Officials worked closely with the International Association of Antarctica Tour Operators (IAATO) to establish better practices that would reduce the carbon footprint and environmental impact of tour ships.
- The system hopes to encourage sustainable tourism to reduce the environmental impacts of the sensitive ecosystem.
Climate change disproportionately affects the Antarctic region, as evidenced by reductions in the size of the Antarctic Ice Sheet and the warming waters off the coast.
- Over the past 50 years, the west coast of the Antarctic Peninsula has been one of the most rapidly warming parts of the planet.
- It has now been established that the Antarctic Circumpolar Current is warming more rapidly than the global ocean as a whole.
- The warming of the Antarctic Peninsula is causing changes to the physical and living environment of Antarctica.
- The distribution of penguin colonies has changed as the sea ice conditions alter.
- The melting of perennial snow and ice covers has resulted in increased colonization by plants.
- Many glaciers have retreated and ice shelves that formerly fringed the Peninsula have been observed to retreat in recent years and some have collapsed completely.
- East Antarctic plateau is changing wind and ocean-current patterns around the continent, and ozone-destroying industrial chemicals have caused a hole in the ozone layer to open above the continent.
The Antarctic has become a symbol of climate change. Scientists and policymakers are focusing on changes in this environmentally sensitive region to push for its protection and the sustainable use of its scientific resources.
Winter heatwave in Antarctica
The temperatures are currently in the range of minus 25 degrees to minus 30 degrees Celsius in parts of East Antarctica, the relatively higher-elevation swathe that makes up two-thirds of the world’s coldest continent.
- For the second time in two years, a record-breaking heatwave is sweeping through Antarctica at the height of its winter season.
- Ground temperatures have been 10 degrees Celsius higher than normal on average since mid-July, and up to 28 degrees higher on certain days.
- Deep-winter temperatures here usually vary between minus 50 degrees and 60 degrees Celsius.
- Scientists believe that the higher temperatures are mainly a consequence of the weakening of the polar vortex, the band of cold air and low-pressure systems that spins around the poles of the Earth in the stratosphere.
- The vortex usually remains strong and stable during winter in the southern hemisphere, keeping cold air trapped over Antarctica and not letting hot air come in. Still, it has been disturbed this year by large-scale atmospheric waves (periodic disturbances in the fields of atmospheric variables).
Read: Polar Code
-Article written by Swathi Satish
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