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Here is a term paper on ‘Climate Change and Antarctica’ for class 8, 9, 10, 11 and 12. Find paragraphs, long and short term papers on ‘Climate Change and Antarctica’ especially written for school and college students.
Term Paper on Climate Change and Antarctica
Term Paper Contents:
- Term Paper on the Introduction to Antarctica
- Term Paper on Antarctic Ice and Icebergs
- Term Paper on the Life in Antarctica
- Term Paper on Recent Climate Change in Antarctica
- Term Paper on the Impact of Climate Change on Antarctic Life
- Term Paper on the Remarks on Climate Change and Antarctic Life
Term Paper # 1. Introduction to Antarctica:
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Antarctica is the fifth largest continent of the seven continents of the world. The continent itself makes up about 9.4 per cent of the land surface of the ice sheets and ice shelves being about 14 × 106 km2. It is roughly circular in outline and forms eccentric hub around the South Pole. The continent comprises the area south of 66°33’S latitude with two deep indentations the Weddell Sea, south of the Atlantic Ocean and the Ross Sea, south of the Pacific Ocean breaking the almost circular landmass.
It contains open water in summer to above Lat. 78°S and floating ice-shelves all the year round extending to about 82°S and 85°30’S respectively at the heads of these seas. The tail of the continent, the Peninsula extending northwards from lesser Antarctica to south American continent at Lat. 63°15’S. The nearest country is Chile (950 km, Lat. 55°50’S), next come New Zealand (2000 km, Lat 46°40’S), Australia (2500 km, Lat 42°50’S) and South Africa (3800 km, Lat 34°24’S). It is over 10,000 km away from India.
Geomorphologically, the Antarctica is twin continents, the Greater and the Lesser Antarctica separated by some deep under ice channels.
Antarctica is divided into three main geographic regions:
i. West Antarctica,
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ii. East Antarctica and
iii. The Antarctic Peninsula.
The West Antarctica is the youngest of the three geographic regions due to the buckling and folding of the earth’s crust, and is characterized by huge mountain ranges both above and below sea level. The Antarctic Peninsula is the northern most section of Antarctica as well as the most moderate in climate due to its latitude. It is an extension of the Trans-Antarctic Mountain Range and is a fertile breeding ground of many life forms.
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About two per cent or 8000 km2 of Antarctic rock and soil are exposed from the ice. The oases in general are continuous ice-free rocky desert-like areas of low precipitation and freezing temperatures with some snow cover in winter in Antarctica and collectively form only a small part of the total land surface of the continent.
Term Paper # 2. Antarctic Ice and Icebergs:
Ninety eight per cent of Antarctica is covered by thick ice sheets that contains about 90 per cent of world’s ‘permanent’ ice and 70 per cent of its fresh water. Sea ice is made of sea water freezing at -1.5°C to -1.9°C. It may be called as fast or pack sea ice as per the location. There are numerous floating slabs of extended land ice sheet, the ice shelves. The Antarctic ice sheets are nearly 2.5 to 3 million years (M.y.) old and have an average thickness of 2,400 m with maximum thickness of 4,786 m at Terre Adelie, about 400 km from the coast.
The thinnest ice sheets are near the centre of the continent. The Greater Antarctica fronts on the Atlantic and Indian Oceans and has an ice dome upto 4,200 m thick ice and the Lesser Antarctica fronts on the Pacific Ocean with ice dome upto 2,000 m thick ice.
Icebergs are large floating mass of ice calved from ice shelves. It is of varying shapes and sizes having a covered area of about 31,000 km2 with about 335 km in length and 97 km in width-the size of Belgium The icebergs generally drift northwards by the ocean currents at a speed of about 10-20 km/day and normally remain within Lat. 50°S – 62°50’S.
Term Paper # 3. Life in Antarctica:
The harshest climate in Antarctica obviously became the greatest hurdle for survival of life there. However, the southern sea surrounding the Antarctic continent is enormously rich in marine life. How the life will survive in a continent like Antarctica 98 per cent of which is covered with 2-3 km thick ice sheet? So the life is very scare on continental Antarctica. Whatever richness of plant and animal is found that is in Antarctic Peninsula and surrounding island where climate is to some extent tolerable.
i. Plants:
Only two species of native flowering climbers viz., the Antarctic hair grass Deschampsia antarctica and a cushion-forming pearlwort, Colobanthus quitensis are found to grow in western coast of Antarctic Peninsula (56°S) and nearby islands like South Orkney Islands and the South Shetland Islands.
Besides these, in other areas of Antarctica, small forms of plants such as algae, lichens and mosses can be found beneath insulating layers of rocks or any other shelter to avoid cold mostly near the coasts and Trans-Antarctic Mountains where rocky lands are present. The most abundant of these three plants is algae. They grow on rocks, ice and in sea.
These blue-green, yellow, orange, brown and grey coloured algae are very old life-form in Antarctica, the age of some algae is 6000 years or more. There are 300-400 species of algae, 200 species of lichen having beautiful colours like yellow, red, white, black, etc., 100 species of mosses and 25 species of liverworts. Mosses mostly grow surrounding the glacier lakes. They maybe deep green or brown in colour and 1 cm to 30 cm thick.
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ii. Animals:
In Antarctica faunal diversity is poor but very rich in population. The terrestrial fauna of Antarctica consists mostly of invertebrates, mostly microscopic living in soil and vegetation.
The invertebrates in the Continental Antarctica include moss and soil inhabiting wingless collembola (Insecta), acarine (Arachnida), nematoda, protozoa, tardigrada, rotifera and wingless midges (Belgica antarctica). Besides these animals, around 65 species of winged parasitic insects are found in Peninsular Antarctica and neighbouring islands. These animals are capable of tolerating very low temperature.
Unlike the Continental and Peninsular Antarctica, the water around Antarctica or southern ocean are teeming with-life of plant and animal species. The most fertile land in the world will loss to southern ocean in respect of production of protein, carbohydrate, fat, sugar, etc. This is due to extreme cold of sea for which the ocean can contain much more oxygen and carbon dioxide. The sea water in winter contains about 95 per cent oxygen.
Due to highly fertile sea the phytoplankton shows enormous growth and very rich in population. As the zooplanktons live on phytoplanktons, they are also very rich both in quality and quantity. The most important and unique zooplankton is a Crustacea-the krill (Euphausia superba).
These pinkish prawn-like animals of 2″ to 3″ long are present in sea in such a number (5-6 billion ton or more) that the colour of water turns reddish. These krills are full of protein and one of the body pigments may be used as medicine of ulcer. The whale, seal, penguin totally live on krill. A whale eats about three ton krill per day.
The other wildlife of Antarctica mostly thrive in the sea are squids, sea anemones, jelly fishes, arrow worms, combe jellies, snails, salps, starfishes, seals, whales, penguins and other sea birds like skuas, terns, petrels and albatrosses.
Fish population in Antarctic sea is very rich and over 200 species are known to live in the water. About 75 per cent of fishes belonging to five families under the order Notothenioidea, a relative of cod fish, make up the fish population.
The blood of some species of fish is white in color due to absent of red blood cells. There are some species like Dissotichus mawsani and Trematomus sp. which can withstand extreme cold for presence of an antifreeze substance glycopeptide which prohibits coagulation of blood.
Antarctic seals include crabeater seal (Lobodon carcinophagus), Antarctic fur seal (Arctocephalus gazella), leopard seal (Hydrurga leptonyx), Weddell seals (Leptonychotes weddellii) and elephant seal (Mirounga angustirostris). Only the Weddell Seals can be found in Antarctica year-round. Other seals migrate to the north by following the pack ice.
Whale the largest mammal can be found in Antarctic waters and only during the summer time. The species of whale found around the Antarctic continent are blue whale, minke whale, humpback whale, fin whale, sperm whale, killer whale (Orca sp.), southern right whale, Arnoux’s beake whale, southern bottlenose whale and hourglass dolphin.
Around 35 species of birds visit Antarctica and nearby islands to breed or live. They range from magnificent wandering albatross capable of flying thousands of kilometers for feeding and mating to gulls, cormorants and terns. Most of them return to the same site each year.
Eighteen species of penguins live south of equator including southern coast of South America, South Australia, New Zealand, tip of Africa and all around Antarctica. One species, the Galapagos penguin, lives on the equator near Peru. Seven species are the regular visitor of Antarctica and only two emperor and Adelie penguins breed exclusively on the Antarctic continent.
Term Paper # 4. Recent Climate Change in Antarctica:
Since the International Geophysical year of 1957-58, Antarctic surface temperatures have remained stable over much of the continent. The majority of stations in East Antarctica showed no significant warming or cooling trends. On the contrary, large and sufficiently significant warming trends are seen at the Antarctic Peninsula.
The most rapidly warming part during the past 50 year’s period is the west coast of the peninsula. The annual mean temperatures at the peninsula have risen by nearly 3°C, with the largest warming occurring in winter. This rate of temperature increase is approximately 10 times the mean rate of global warming as reported by the Intergovernmental Panel on Climate Change. The east coast of the peninsula warmed slowly showing largest warming in summer and autumn.
The Southern Ocean showed significant warming. Upper ocean temperatures to the west of the Antarctic Peninsula showed an increase by over 1°C since 1955. It is well established that the waters of the Antarctic circumpolar current are warming more rapidly than the global ocean as a whole. This rate of warming is of around 0.2°C at 700-1000 m depth.
The result of study of vertical warming over the last 30 years has shown that Antarctic atmosphere has warmed below 8 km and cooled above this height. This trend of warming in the troposphere and cooling in the stratosphere indicates increase in greenhouse gasses, such as carbon dioxide.
Year round satellite observations on Antarctic sea ice extent has indicated that sea ice cover has declined substantially in the seas to the west of Antarctic Peninsula while it has increased in other parts of the Antarctica. The reports on atmospheric circulation around Antarctica mentioned that atmospheric pressure has dropped over Antarctica and risen in the mid-latitudes of the southern hemisphere.
The ice cover of the peninsula has largely changed, many glaciers have retreated and around 10 ice shelves have been observed to retreat in recent years and some have collapsed totally. Eighty seven per cent of glaciers along the west coast of the peninsula have greatly retreated resulting sea-level rise at about the same rate as Alaska glaciers.
The climate change has weakened the carbon sink of the Southern Ocean since 1981. This is due to increased upwelling of carbon-rich waters associated with strengthening of the westerly winds. The analysis of the result of works of different climate models by IPCC showed greatest warming in the peninsula region and little change elsewhere.
Term Paper # 5. Impact of Climate Change on Antarctic Life:
The recent climate change in Antarctica has made significant changes in the physical and biological environment. The environmental changes are most remarkable in the Antarctic Peninsula, where climate change has been most significant. The study conducted by Doran et al. (2002) in the McMurdo Dry Valleys had evidenced rapid terrestrial ecosystem response to climate cooling in Antarctica.
Their spatial analysis of Antarctic meteorological data showed a net cooling on the Antarctic continent between 1966 and 2000; particularly during summer and autumn. They reported decreased primary productivity of lakes (6 – 9 per cent per year) and declining numbers of soil invertebrates (more than 10 per cent per year). Fourteen years of continuous weather recording from the shore of Lake Hoare by them revealed that seasonally average surface air temperature has decreased by 0.7 per cent per decade.
The temperature decrease was more pronounced in summer and autumn. Winter (June-August) and spring (September-November) showed smaller temperature increase. They opined that climate cooling has significantly impacted ecosystem properties. They also reported decrease in irradiance during November-December which affected the rate of primary production in the lakes.
Soil invertebrate communities showed changes in diversity and abundance from 1993 to 1998. The abundance of tardigrades and nematodes were specially declined even after climate manipulation experiment. This indicates that change in climate in Antarctica has declined the diversity, life cycle, trophic relationships and functioning of dry valley soils.
It is difficult to assess the response of soil organisms to the climate change. However any change in the climate will consequently affect the soil organisms in their density and biomass. Soil organisms play a significant role in soil nutrient cycling, decomposition of organic wastes and biodegradation of the major hydrocarbons as soil spills. The fauna is moderately abundant in Antarctic soil and vegetation.
It’s a fact that soil is a thermally buffered environment that responds slowly to temperature changes in their column above. Therefore, the biota living within the soil is less likely than the surface vegetation to show large responses to changes in atmospheric temperature. Although climate does not have direct effects on soil biota, soil biota are more strongly affected by vegetation than they are by atmospheric conditions directly.
This is for two reasons:
(1) The physical structure of the vegetation affects the soil temperature and moisture, and
(2) Vegetation provides vast amount of organic matter (i.e. energy supply) and nutrients which may affect the species composition and structure of the soil biotic communities.
This phenomenon has been observed correct in Antarctic Peninsula, where melting of perennial snow and ice covers encouraged the growth and spreading of established plants and increased establishment of seedlings. The increase in abundance in vegetation has resulted increased abundance of soil and other terrestrial fauna in some sites of Antarctic Peninsula.
Plant responses to atmospheric CO2 increase, to global warming and to increased ultraviolet-B radiation as a result of stratospheric ozone depletion. Changes in temperature and precipitation have increased biological production in lakes, mainly due to decreases in the duration and extent of lake ice cover. Some lakes have become more saline due to drier condition, and resulted depletion of Lake Biota.
The review of studies done during 1985-2000 by several Indian scientists including the author in the Schirmacher Oasis, East Antarctica revealed that the faunal density in soil and lake waters was much higher in the year 1987. The result also indicated that the population of microscopic protozoa and nematoda was much more in 1996 and decreased later.
Mitra (1999) observed dominancy of immature forms of protozoa, nematoda and acarina and stated that it was due to suitable environment for reproduction. Sanyal (2004) reported that mite population was more in quantity and quality that the earlier records in the Oasis.
Compared to many marine organisms the terrestrial biota in Antarctica often has a wide environmental tolerance. It includes some of the most robust life forms on earth, the cyanobacteria, which can survive extremes of low temperature, water availability, light and high UV radiation.
Environmental change is most apparent in the Antarctic Peninsula, where climate change has been largest. The changes have declined in number of Adelie penguins, a species well adapted to sea ice conditions, and been replaced by open-water species such as chinstrap penguins. The number of emperor penguins has dropped from 300 breeding pairs to just nine in the western Antarctic Peninsula.
The Antarctic marine ecosystem is also severely affected by climate change, especially on the western side of peninsula, with its warm water and reduction in sea ice. Among the significant cases of decline in population of different marine fauna, decline in Antarctic krill stocks, decrease in phytoplankton and southward shift in the population of gelatinous salps are noteworthy.
The decline in phytoplankton may reflect a decrease in iron input form the continental margin that is in turn related to a reduction in the formation of sea ice in this region and hence to climate change. There are records of decline in population of fish especially Pleuragramma antarcticum, whose reproduction is associated with sea ice. Antarctic marine animals are of typical stenothermal in nature which would be highly sensitive to significant warming.
Most species have upper lethal temperature below 10°C and some can survive just a 5°C change. The behavior of organisms can be affected at lower temperature long before lethal levels are reached. The question whether the rise may depend upon their ability to carry out critical activities like feeding. The planktonic snails, key species in food chain, could suffer from ocean acidification. This decline in food regime is likely to affect the Antarctic sea bed biodiversity.
The increase in temperature in terrestrial ecosystem promote growth and production of biota, but also cause drought and associated effects. Water availability would have greater effect on vegetation and faunal composition than temperature. An increase in the frequency and intensity of freezing events could readily exceed the tolerance limits of many arthropods.
With increase in temperature many terrestrial species may exhibit faster metabolic rates, shorter life cycles and local expansion of population, which is presently observed in Peninsular Antarctica. Warming also favours alien species to migrate and settle into the region, competing with and replacing original Antarctic inhabitants.
Term Paper # 6. Remarks on Climate Change and Antarctic Life:
The analysis of instrumental data from some limited research stations in Antarctica revealed that Antarctica have undergone complex and significant temperature changes in recent decades, with greatest warming in the peninsula region and little change elsewhere. Recent climate observations indicate that changes in the strength of the waster lies strongly influence temperature variations on the east coast of the Antarctic Peninsula.
Contrary to this, the interior parts of East Antarctica have experienced less warming, with large spatial variability. It is evidently difficult to separate natural climate variability and anthropogenic influences. However, the effect of greenhouse gases are already evident and if they continue to rise at the current rate, some catastrophic effects on physical and living environment of Antarctica are inevitable.
We can make reasonably a broad estimate of how the parameters of physical environment like temperature, precipitation and sea ice extent might change and consider the possible impact on terrestrial and marine biota. Antarctica is earth’s most powerful natural laboratory, a pivotal part of the earth’s climate system and a sensitive barometer of environmental change. For peaceful sustenance of life on earth, the Antarctic continent must be saved along with its fragile environment.