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Antarctic Oceanography (General Information and Student Activities) |
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Lesson 1. - Overview and Research Stations |
| Antarctica is a continent located at the southern-most point of the globe. Millions of years ago, this landmass was attached to a giant landmass called Gondwanaland that consisted of modern-day South America, India and Africa. Powerful internal
earth forces ripped a large piece of land from this giant landmass, which then drifted to its current position at the bottom of the globe. It is surrounded on all sides by the Indian, Pacific and Atlantic Oceans.
Antarctica's cold, thick hard covering,  called an ice sheet, began to form 25 million years ago. The ice in Antarctica locks up more than two-thirds of the planet's fresh water. If the Antarctic ice were to melt, the sea would rise  |
 Antarctica is considered the coldest and driest continent on decrease as one moves from the coastal regions inland. Temperatures during the long, dark winters range from -4° F to -22° F on the coast, -40° F to -90° F inland. During the summers, coastal temperatures average 32° F (occasionally climbing to 50° F), while the inland summer temperatures range from -4° F to -31° F. The lowest temperature recorded in Antarctic history was in 1983, a chilling -129o F. This is colder than the surface of Mars. When water was thrown into the air, it froze before it hit the ground.
Antarctica receives less snow than you may think. Actually, it only snows an average of 10" per year on the coast, and less earth. Temperatures than 2" inland. Because it is so cold, the snow never melts. Blizzards are produced not by falling snow, but when high winds (100- 200mph) blow ground snow around, creating blinding conditions and snowdrifts that can cover local research stations in an hour.
The snowfall has accumulated over several million years to make Antarctica's average elevation 2.5 miles above sea level, making it the highest continent. But in a sense, it is also the lowest continent: the landmass itself, because of the weight of all that snow, has been pushed down so heavily that some parts of the continent are actually below sea level.
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History |
| Aristotle, an ancient Greek philosopher, believed that if the world was round, then there must be a continent at the bottom of the globe holding all the other continents in place. He named the continent Antarktikos, meaning "anti-Arctic". Most believe that the first man to sight Antarctica (in 1820) was Fabian von Bellingshausen, a Russian explorer. Others believe it to be a British seaman named Edward Bransfield. Captain John Davis, a US sealer, was the first to set foot on the continent. James Weddell, an English sealer, had both a seal and a sea in the Antarctic named after him.
In 1911-1912, the first men to reach the South Pole were two |
teams led by Ronald Amundsen from Norway and Robert F. Scott from Great Britain. Scott made it to the South Pole 10 days after Amundsen, who had left his country's flag at 0o to let Scott know he had made it first. Amundsen left supplies behind for Scott, but because of poor preparation on their part, Scott and his team perished from cold and starvation on the way back to their camp. |
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Research Stations |
| Having been isolated for so long, Antarctica provides numerous opportunities for scientists to conduct research. By the mid 1950s, seven countries had claimed territories of Antarctica as their own, establishing year-round research stations there. Soon five more nations were expressing an interest in the continent for research purposes. An 18-month period from 1956-57 was declared the International Geophysical Year (IGY). These twelve countries came together in the interests of science and discussed how they could help each other in terms of locating and building research bases, setting up communication systems, launching rescue operations and sharing weather reports. They, and eventually 45 more nations, spent the IGY cooperating with each |  other on various scientific and research projects. This period of harmony led to the signing of the Antarctic Treaty in 1959, declaring Antarctica as an international research preserve. This treaty took effect in 1961, and since then, many other countries have agreed to it. The preamble to the Antarctic Treaty clearly sets forth its purpose: |
Recognizing that it is in the interest of all mankind that Antarctica shall continue forever to be used exclusively for peaceful purposes and shall not become the scene or object of international discord; the establishment of a firm foundation for the continuation and development of such cooperation on the basis of freedom, of scientific investigation in Antarctica as applied during the IGY accords with the interest of science and the progress of all mankind." |
| The treaty states that Antarctica will remain open for research for any scientists from nations who agree to the treaty. It also calls for a ban on military and weapons (including nuclear) testing; international cooperation and freedom of scientific investigation; and free exchange of science program plans, results and personnel. This treaty guarantees that no country's claim on any territory will ever be acknowledged by the other parties. Any disputes are to be settled by the International Court of Justice. The Treaty was re-examined in 1991, 30 years after signing, and re-affirmed. Some of the modern research stations, especially the larger ones, are like small towns. McMurdo Station, the principal U.S. facility, on Ross Island, coast of Antarctica (peak summer population capacity 1,258; 1996 winter, 232) is Antarctica's largest station, it has airports and a seaport | research laboratories and support facilities.
McMurdo is built on the bare volcanic rock of Hut Point Peninsula on Ross Island, the most southerly solid ground that is accessible by ship. It is located just 20 miles south of Mt. Erebus, an active volcano that steams continually and erupts frequently though not violently.
Heat and lighting is provided by small power plants. The buildings must be designed to withstand blizzards, and due to the dry conditions, fire remains a major threat. The base is run by an administrative director, who is not necessarily a scientist. The base requires personnel to perform a myriad of tasks: cooks, bulldozer  |
| operators, pilots, mechanics, communication specialists. Some bases even have chaplains to help those on the base deal with the isolation and the cramped living conditions.
Although nations build their own bases, it is not unusual to have scientists from many nations working together on research projects at one base. There are 40-50 research stations in Antarctica, and more than 50,000 people from over 25 different countries work on these bases. |
One of the problems created by the research stations is the accumulation of trash. Garbage does not break down or biodegrade in the frigid climate. Piles of trash that accumulated over the decades of research, including thousands of oil barrels and broken or abandoned machinery, littered the landscape. Many nations have instituted cleanup procedures and now all nations must transport trash from the Antarctic continent back to their countries. |
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The Oceans that Surround Antarctica |
| Antarctica is surrounded on all sides by water; the Atlantic, Pacific and Indian Oceans all meet at Antarctica. The three oceans are collectively called | the Southern Ocean. This is the area located south of 50° latitude. |
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The Antarctic Divergence |
| The East-Wind Drift drives the waters closest to Antarctica, which move in a westerly direction around the continent. Further out from the continent the waters are driven by westerly winds called the West- Wind Drift. These westerly winds remain strong through out most of the year. | In the Southern Hemisphere, the Coriolis Effect deflects moving masses to the left. The inner East-Wind Drift moves toward the continent while the outer West-Wind Drift moves away from the continent. This creates an area of divergence called the Antarctic Divergence. |
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The Antarctic Convergence |
| the irregular ocean zone that surrounds Antarctica. It is where warm deep water from the northern oceans collide with colder surface water from the Southern Ocean and the colder bottom water. Because the colder water is saltier, and therefore more dense, it flows beneath the warmer water. This convergence brings the rich nutrients from the warmer | waters into the cold water of the Southern Ocean.
These nutrients are necessary for photosynthesis and create the perfect environment for zooplankton and phytoplankton to thrive. Because phytoplankton are so abundant, they form the foundation of the food web. A small shrimp-like creature called krill feeds on the phytoplankton. |
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Krill |
| Krill is a general term used to describe about 85 species of crustaceans found in open oceans. They belong to the group of crustaceans called euphausiids and look like much smaller versions of familiar crustaceans such as shrimp or lobsters. They range in size from small tropical species of less than a centimeter in length to little known deep-sea giants that can reach 14 centimeters. Krill usually feed on the surface of the water at night and often sink deeper in the water column in the daytime. | The primary food of krill is phytoplankton, which are microscopic ocean plants suspended in the upper water column where light is sufficient to allow for growth. Most of the Antarctic creatures, everything from penguins to whales, feed on krill. Without it, the ecosystem would collapse. |
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Activity 1-1. Classroom Discussion Questions |
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Activities 1-2. Interaction of Sea Ice and Water |
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Activity 1-3. Sea Ice and Its Effects on Water Temperature |
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Activity 1-4. Join Admunsen and his Team on a South Pole Expedition |
Write a short essay on one of the following:
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Activity 1-5. Classroom Discussion Part II. |
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Compare a map of Antarctica and the Arctic Circle. Make a list of the differences and similarities of these two areas.
Why are the polar lands sometimes called the high latitude lands? Use an atlas to find out the latitude of the Antarctic Circle. What is the latitude of the South Pole? If the nations of the world decided to allow no more developments (mining, industrial etc.) in one of the Polar Regions, which one should it be and why? What would be the benefits of that decision? |
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Lesson 2. Antarctic Oceanography: Component I - Ice/Glaciers Component II - Marine Snow |
Lesson Objectives:
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Component I - Ice/Glaciers |
| Antarctica's cold, thick hard covering, called an ice sheet, began to form 25 million years ago. Approximately 98% of Antarctica is covered by ice. Antarctica actually changes size - during the summer months (December to about March), the coastal ice melts and Antarctica "shrinks."
Although almost all of Antarctica's land mass is covered by ice, in a few places on the continent, mountain peaks poke through. The Transantarctic Mountains divide the areas of the continent known as West and East Antarctica. A glacier is a huge mass of ice, formed from compacted snow, |
whose sides are often bounded by mountains or the walls of a valley. Ice sheets, or caps, which are also formed from compacted snow, are so massive that they cover entire landscapes, mountains as well as valleys. Glaciers and ice sheets flow slowly toward the sea where the temperature is slightly warmer. This causes chunks of ice to break off; since ice is lighter than water, it floats when it reaches the sea. Once these chunks of ice are free-floating, they are called icebergs. The process of "birthing" an iceberg is called calving. Only about one-tenth of the iceberg is visible above water. The largest iceberg ever recorded measured 200 miles by 60 miles. |
| Parts of the West Antarctic ice sheet rest on the sea floor and land. Scientists carefully monitor it to see whether it will be affected by global warming. If the temperature rises, large parts of the ice sheet will melt and float freely. As they float, these ice sheets will move | are less stable than the ice on toward a warmer climate and begin to melt, leading to a sharp increase in sea level which would cause severe flooding on a global scale. |
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Component II - Marine Snow |
| Marine snow is the debris or dust that falls through the oceans and settles on the sea floor, the same way as dust in the air settles on an object in your home. The difference is that this ocean dust is full of nutrients and life. Marine snow helps transport material from the surface ocean to the deeper layers of the sea. Scientists believe marine snow is a major food source for life in the abyssal deep, bringing important nutrients into the deep sea while carrying with it diverse populations of microorganisms. This marine snow consists of bits of dead animals and plants bound together by mucus, which is produced by the ocean dwellers. The mucus glues together scraps of crustacean shells, remnants of plants and excrement of animals. The particles are all different shapes | and denser than the surrounding ocean, but have many cavities. While the particles have to be at least one-half millimeter in diameter to be considered snow, they can grow to be quite large, on the order of feet, but these are rare. Most marine snow in the ocean is 1-2mm in size. Marine snow plays an important ecological role by moving atmospheric carbon from the surface of the oceans to the seafloor. This can affect the climate over thousands of years by removing carbon from the atmosphere and transporting it to the deep sea. Atmospheric carbon dioxide dissolves in the ocean water, and algae take up the gas as they photosynthesize, converting the atmospheric carbon into plant carbon as the algae grow. The algae contribute to the formation of the debris that sinks through the |
| ocean in marine snow. Some small percentage of the total carbon remains at the bottom of the ocean as marine snow and is largely consumed by benthic (bottom dwelling) organisms. This percentage can be as high as ten percent of the total carbon in coastal waters and less than one percent in the deep oceans.
Sinking marine snow in the Antarctic is primarily made up of algae and so it is an important source of organic carbon and silica to the deep Antarctic waters and the sediments. The silica is contained in the tiny algal cell skeletons that are of intricate shape and design. There is a very short season between approximately late November and February in the Antarctic (called the "austral spring and summer") when every year algae grow very rapidly due to the high amount of sunlight and the supply of important nutrients from upwelling deeper waters. During this time of rapid algal growth, which we call a "bloom", large amounts of marine snow containing algae are formed and sink rapidly through the ocean. In addition, abundant krill feeding on the |
blooming algae produce lots and lots of fecal pellets that sink to the deep-sea. This process of marine snow and krill fecal pellets settling into the deep Antarctic over millions of years has transported huge amounts of algal materials to the Antarctic sediments. The result is that these sediments contain the world's largest amounts of algal skeletons made of silica.
Geological oceanographers who study ocean sediments, study the Antarctic sediments and the algal skeletons in sediment cores they obtain from the seafloor. The cores are often many, many feet long, and are collected with special equipment on oceanographic research vessels. Sediments and algae in the cores which have been deposited over millions and millions of years are used by scientists to look at how the algae populations have changed through time. Such changes are usually the result of changes in the ocean environment where the algae lived and are caused by climate variations affecting the water temperature, circulation patterns, and nutrient levels. |
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The Greenhouse Effect |
| The greenhouse effect is a condition that causes the average global temperature to rise over a period of time. Carbon dioxide and methane, two gases in the atmosphere, absorb heat as it radiates from the Earth's surface. They act like the glass in the greenhouse, not allowing the outgoing heat to radiate back out into space, thus the term "greenhouse effect". With modern industry, we have put new greenhouse gases into the atmosphere, nitrous oxide and chlorofluorocarbon. These gases come from sources such as car exhaust and aerosol sprays. As the amount of greenhouse gas increases, the Earth's temperature will rise. If that happens, some polar ice can melt and there will be a rise in sea level, flooding coastal areas and cities. Another effect | is a change in weather patterns.
The increase in CFC's in the air also causes a thinning of the ozone layer in the air. This ultimately affects marine life in Antarctica. With less ozone in the atmosphere, more ultraviolet radiation reaches the Earth. Higher ultraviolet may have damaging effects on the ability of phytoplankton to grow in the Antarctic surface waters. If so, there may be less food (phytoplankton) for the krill to feed on. Less food for the krill means less krill; less krill means that the Antarctic animals that feed on and survive on krill will suffer. Because it is so cold in Antarctica, the ozone thins out even more than elsewhere on the globe. |
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Activity 2-1 Classroom Discussion |
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Lesson 3: Antarctic Oceanography-Animals: Penguins, Seals and Whales |
Penguins are flightless birds found only in the Southern Hemisphere. They appear  clumsy on land but very agile in the water. Their wing- like flippers helps them dive and swim through the icy waters. There are a number of penguin species found in Antarctica (see table), but only the Emperor lives on the ice shelf.
In March, female Emperor penguins |
 come ashore to claim their breeding ground and mate. In May or June, she lays her egg. The female goes to sea to feed and leaves the egg with the Emperor male, who holds the egg on his feet and warms it with folds of loose skin. This incubation lasts for two months. The males must survive on stored body fat for that duration. After feeding for several weeks, the females return and the male must then make the trek back to the sea to feed, which often can be several miles from the nest site. He needs to renourish himself and bring back food for the female and the chick. The |
 Emperor chick is cared for by its |
parents until it is able to care for itself, usually at about 5 months of age. |
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Seals |
The common seals found in Antarctica are the Weddell, Ross, Crabeater, Leopard, Southern Elephant and Antarctic Fur Seal. Other than the Fur seal, they are all "earless" seals, meaning they have no external ear structures, but they have excellent hearing both on land and in the sea. Like penguins, the earless seals move awkwardly on land but are quite agile in the water. The Fur seal has longer flippers than the others, so it moves well on land as well.
Weddell seals can dive down 2000 feet in search of fish, using sonar to locate their food. Since they require air to breathe, they can cut holes in  the ice for air holes using their sawlike teeth. The Weddell seal can stay underwater for up to an hour at a time
Ross seals are the smallest and least plentiful of the Antarctic seals. They live on thickest areas of seasonal pack ice. Leopard seals are fierce predators. They are found in the sea near areas where penguins breed, so they can |
feed on the flightless birds. The females are ten percent larger than the male.
Crabeater seals are the most common large seal on earth, numbering around 40 million. Despite their name, they do not feed on crabs; they feed on krill. The females are slightly larger than males.
The largest seal is the Elephant Seal, which gets its name from a large proboscis, or trunk. The males can inflate this trunk to attract females and scare off other males. The male, which can weigh up to four tons, is much larger than female, which weighs about one ton.
The Antarctic Fur seal is an eared seal, meaning it has visible ear structures. Its fur has two layers - an outer layer of coarse hair and a thick velvet-like inner layer. Because of their beautiful fur, these seals were hunted almost  to the point of extinction. The populations of the Fur seals are once again increasing thanks to international laws banning the hunting of them
All seals have fish in their diet, while some species also eat krill, squid, penguins, octopus and/or crustaceans. |
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Whales |
| There are two types of whales found in Antarctic waters, Southern baleen whales and toothed whales. They are so categorized by the structures found in their mouths to feed. The baleen whales have a bristly substance (baleen) in their mouths. This baleen is attached to plates on the whale's gums, and it serves as a filter by which the whale can strain krill, its main food source. The toothed whales have teeth, and therefore can eat much larger animals.
The major species of baleen whales found at least part of the year in Antarctic seas are: Blue, Fin, Sei, Minke, Humpback and Southern Right whales. Humpback whales have been observed herding krill into a circle, causing the krill to swarm into a more compact group. The whale then dives and rises up beneath the concentrated krill with its mouth open, ending up with a mouthful of food. |
The Blue whale is not only the largest of the baleen whales, but also largest creature that has ever lived on the earth (the largest one measured 124 feet in length). Before hunting whales for blubber and oil became popular, there were 200,000 Blue whales; now there are only approximately 1000 left in existence. All whales in the Antarctic are now protected by international agreement, however there are still countries that hunt the whales for precious food and oil in other parts of the world.
The two most common toothed whales found in the Antarctic are the Sperm Whale and the Orca, the killer whale. The sperm whale is the largest of the toothed whales, measuring approximately 60 feet in length and weighing 70 tons. The toothed whales' diet consists of fish, squid, birds, penguins and seals. |
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What to do if you come across a stranded whale Source: http://www.clearlight.com/~kid/whales/hbwhales.html |
| A stranded whale is one that has beached itself ashore for some reason. They can be found anywhere throughout the world. If you are the first to come upon such an unfortunate creature, there are a number of things you can do to help its rescue:
The first thing you should do is contact the nearest office of the national parks or wildlife department to summon help from experienced persons. You will need to tell them the exact location of the stranded whale and give an accurate description of its type, condition and health. If you are unsure of the type you should take notes as to its size, body shape, color, the size and positions of its fins, the location and number of blow holes, and whether or not the stranded whale has throat grooves. |
Out of the water, stranded whales will find it very difficult to maintain correct body temperature. A rapid rise in body temperature will result in death in a few hours. Pouring buckets of seawater over the skin will ensure it stays cool and wet. Never pour water in the blowhole! These mammals breathe air through their blowhole and pouring water in there will cause them to drown.
Covering exposed areas of the skin with water-soaked hessian bags or something similar will help with cooling and also help prevent sunburn. Once again, do not cover the stranded whale's blowhole ! Also, do not cover the fins, as these areas are used to lose heat from the body.
When the wildlife officers arrive, follow their instructions exactly. They know best what to do for beached whales |
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Fun Facts |
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Activity 3-1. Classroom Discussion |
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Activity 3-2. Antarctic Features http://quest.arc.nasa.gov/antarctica2/main/t_guide/blackline_2.html Locate as many of these creatures and geographic features on an Antarctic map as you can. Watch out - some of the creatures do not belong in the Antarctic! |
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| Geographic Features
Amundsen-Scott South Pole Station Antarctic Circle Antarctic Convergence Antarctic Ocean Antarctic Peninsula Anvers Island Balleny Island Beardmore Glacier Bouvet Island East Antarctic Ice Sheet Ellsworth Mountains Geographic South Poles Geomagnetic South Pole Gerlache Strait Heard Island Indian Ocean King George Island Magnetic South Pole Marie Byrd Land McMurdo Dry Valleys McMurdo Station Mount Erebus Palmer Station Ronne-Filchner Ice Shelf Ross Ice Shelf Ross Island Rothera Scott Base Sentinel Range South Atlantic Island South Georgia Island South Orkney Island South Pacific Ocean South Sandwich Island South Shetland Islands Transantarctic Mountains Vostok Victoria Land Weddell Sea |
Creatures Adelie penguins Antarctic hairgrass Beluga whales blue whales dinosaur fossils elephant seals Emperor penguins endolithic organisms finback whales indigenous peoples, such as Eskimos international research stations kraken leopard seals lichens Macaroni penguins ostriches pearlwort polar bears sei whales skuas USAP field teams USAP research stations walruses Weddell seals |
| For more activities like this one please visit NASA Passport to Knowledge, Live from Antarctica 2 http://passport.ivv.nasa.gov/antarctica/teacherguide.html |
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Activity 3-3. Penguin Adaptation |
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Source: NASA Passport to Knowledge, Live from Antarctica 2 http://passport.ivv.nasa.gov/antarctica/teacherguide.html
Objectives: Students will investigate animal adaptations to a cold environment and incorporate key findings by designing an organism well-adapted to this environment. Students will demonstrate the ability to predict animal behavior patterns by simulating penguin foraging activity. Engage: Brainstorm ways in which penguins are well adapted to cold water and icy environments. Then complete the following demonstrations:
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Activity 3-4. Antarctic True or False |
Source: http://quest.arc.nasa.gov/antarctica2/main/t_guide/activity_A1.html
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Activity 3-4a. Antarctic True or False Teacher's Key |
Source: http://quest.arc.nasa.gov/antarctica2/main/t_guide/activity_A1.html
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Vocabulary |
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Algae- Small plants that often grow in water or in damp areas.
Antarctic Circle-Line of latitude at 66o 32' south. Along this line there are 24 hours of daylight on Midsummer Day and 24 hours of darkness on Midwinter Day. Antarctic Convergence- The circular region around the Antarctic, located at approximately 50o S, where cold bottom waters from the southern ocean converge with (meet) warmer bottom waters from oceans to the north. This convergence brings nutrients (foods) to the surface. Antarctic Divergence- The region surrounding the Antarctic and very close to the continent which marks the boundary between two large currents - the clockwise flowing West-Wind Drift, and the counter-clockwise-flowing East-Wind Drift. Antarctic Ocean- General term given to the seas surrounding the continent of Antarctica. Atmosphere-The layer of gases surrounding the rocks and seas of the earth. Baleen- The rows of thin, flexible strips in the jaw of a toothless whale that allow it to sift small animals out of seawater. Blizzard- Blinding snow storm, especially one where powdery snow is swept up from the ground by a high wind. Blubber- A thick layer of fat on a whale, seal, or penguin. Calving- The separation of a piece of ice from a larger ice mass to form an iceberg. Carbon Dioxide- (CO2): A gas that is naturally found in the air. CO2 also comes from burning wood, from running vehicles on gasoline, and from exhaling. Chlorofluorocarbons- (CFC's) Chemicals made up of chlorine, fluorine, and carbon Gases used as coolants in refrigerators and air conditioners, and as foaming agents for insulation and food packaging. In the upper atmosphere, chlorine from CFC's destroys ozone that protects life on earth from the harmful ultraviolet radiation of the sun. Use of CFC's as propellant gases in aerosol cans has been halted in most nations, and there are international agreements to further reduce CFC production. Climate- The average long-term atmospheric conditions, including temperature, wind, and precipitation, that prevail in a particular place. Climates of small areas- like the north side of a tree trunk-are called microclimates. Conservation- To protect what is good, to preserve a resource from damage by exploitation. Continental Drift- The movement of land masses of the world towards or away from each other .The process by which the earth's continents change position. About 200 million years ago they were joined in a single land mass. They continue to move and will change their positions. The continents and ocean basins are carried on 20 plates, about 60 miles thick, that make up the earth's crust. Continental Shelf- The part of a continent which lies off-shore and is covered by a shallow layer of water or, in the case of the Antarctic, ice. Continental Slope- The slope which joins the end of the continental shelf with the deeper part of the ocean. Core Sample- A long narrow column of material obtained by drilling deeply with a hollow tube. In Antarctica, the drill gathers samples from many different layers of ice that formed millions of years ago. Crustacean- Animal (usually living in the sea) with hard shell and many legs. prawns, crabs and lobsters are all crustaceans. Environment- The surroundings of living things; everything that affects the way animals, plants, and people live. Exploitation- The selfish taking of any resource from an environment without putting anything back. Extinct- No longer existing. Food Web- A group of plants and animals, each of which is a source of food for the next number in the web. Frostbite- A very painful injury that results from exposing the body- especially the ears, nose, hands , and feet- to extreme cold. Glacier- A huge mass of ice, formed from compacted snow, whose sides are often bounded by mountains or the walls of a valley. Ice sheets or caps, also formed from compacted snow, are so massive that they cover entire landscapes, mountains as well as valleys. Glaciers and ice sheets flow slowly toward the sea, where chunks break off and are called icebergs. Glaciologist- A scientist who studies ice and snow. Global Warming- The gradual warming of the earth's atmosphere that most atmospheric scientists now believe is under way. Human activities that add carbon dioxide, methane and other heat-trapping gases to the atmosphere may cause enough warming to raise sea levels, change rainfall patterns, and threaten crops, water supplies, wildlife and coastal cities. Greenhouse Gases- Gases in the atmosphere that re-radiate heat energy back to the earth, such as CO2 (carbon dioxide) and the CH4 (methane). Greenhouse Effect- The result of the sun's heat becoming trapped in the atmosphere by gases in the same way that glass traps heat in a greenhouse. Ice Age (also called Glacial Period)- A period of time in earth history when the earth received less heat than at present, and when the planet was partially covered by large ice sheets and glaciers. Ice floe- A thick, flat chunk of floating pack ice, broken off by the action of waves. Ice Sheet- A vast, flat mass of ice and snow that covers a large land area. Ice Shelf-Vast floating sheet of ice attached to a coastline, fed by glaciers descending from the mountains. Ice- Water frozen solid, ice occurs in its greatest variety in the coldest place on earth, the Antarctic. At least 78 different forms of ice have been named. They include bullet ice, frazil ice, grease ice, green ice, ice flowers, ice saddles, and pancake ice. Iceberg- A piece of ice made up of fresh water that has completely broken off from an ice shelf or glacier and floats in the sea. In most cases, only a small part of the iceberg can be seen above the ocean's surface. Icebreaker- Ship which has been reinforced to allow it to force a passage through pack ice and fast ice. Incubate-To warm an egg with the body so that the egg can hatch. Interglacial- A period of time when the earth warmed up. Ice sheets melted back and covered smaller areas. Katabatic Wind-A fierce wind caused by the rapid flow of cold air down a mountain slope. Krill- Small, shrimp-like animals which form the main food of many whales, seals, penguins and other birds. Antarctic krill is a special species known as Euphausia superba. Latitude- Lines of latitude are imaginary circles around the earth. They are measured in angular degrees, north and south of the Equator. Migrant- An animal which survives by moving from one environment to another to take advantage of seasonal food sources. Nutrients- Biochemicals (e.g. nitrate, phosphate) present in sea water and produced by the decay of dead plants and animals. Ocean Sediments- Clay, sand and silt which collect on the sea floor and which often contain the tiny shells and skeletons of phytoplankton and zooplankton. Orbit- The course the earth and the other planets follow around the sun. Ozone- A form of oxygen (O3) present in the earth's atmosphere in small amounts. A layer of ozone, between fourteen and nineteen miles above sea level, makes life possible by shielding the earth's surface from most ultraviolet rays. Pack Ice- used interchangeably with sea ice and ice pack. This is the final stage of sea ice formation. Continued thickening and growth of ice results in large, thin sheets of ice floating at the ocean surface. Photosynthesis- The chemical process by which plants make their own food. the process uses carbon dioxide, water, nutrients and sunlight. Phytoplankton-Very small plants, of the plankton group, usually single celled, which float and drift in the oceans. Plankton- Tiny animals (zooplankton) and plants (phytoplankton) which drift in millions through the seas. They are the first links in the food web. Polar Plateau-3,000-metre high plateau leading to the South Pole. Pollution-Contamination of seawater by dangerous chemicals from industry, oil spillage and sewage or other rubbish. Precipitation- All the forms of water deposited on the earth from the atmosphere. They include rain, snow, frost, hail, dew, etc. Roaring Forties- Fierce westerly gales which occur between latitudes 40 and 50 south South magnetic Pole-The point to which a compass is attracted and which is some distance from the geographical South Pole. It varies from year to year as the Earth's magnetic field changes South Pole- The permanently fixed geographical point (90° South) around which the Earth rotates. Species- A group of organisms that have a common ancestor and that are able to reproduce only among themselves. Sub-Antarctic- Describing the seas and islands north of the Antarctic Convergence. Sub-Antarctic water meets Antarctic water along the Antarctic Convergence. Swell- Heaving of the sea, with long rolling waves which do not break. Swell is common after a storm. Tides- The rise and fall of the surface of the sea which depends on the attraction of the Sun and the Moon. In the Antarctic, there may be one or two tides in a day. Ultraviolet Radiation- Invisible radiation from the sun that has shorter wavelengths than visible violet light. Ultraviolet light includes tanning rays, but also more powerful wavelengths that cause sunburn and skin cancer. Most of these harmful rays do not reach the earth's surface because they are blocked by a layer of ozone gas in the stratosphere. Ultraviolet (UV) Light- A ray of sunlight that humans cannot see directly. The shortest UV rays harm living things, and only some of the rays are absorbed by the Earth's ozone layer. Whiteout- A weather condition in which loose or falling snow is blown into a dense blizzard, blocking vision and preventing movement. Zooplankton- Tiny animals of the plankton group that are able to propel themselves through the water. |
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Timeline of Important Dates in Antarctic History |
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???-Aristotle names Antarctica "Antarktikos" 1773- Captain James Cook crossed the Antarctic Circle while searching for the southern continent. 1820- The Antarctic continent is sighted for the first time 1821-John Davis makes the first landing on Antarctica 1822-James Weddell launches a sealing expedition in southern waters with two ships 1823-Weddell lands in the South Orkneys 1840-French d'Urville expedition crossed the Antarctic Circle and sights Antarctica 1842-English expedition under James Clark Ross explores and names Mount Erebus and discovers what is now called the Ross Ice Shelf 1875-Karl Weyprecht, an Austrian naval officer, proposes that all scientific programs in both the Arctic and Antarctic be coordinated 1882-83-The first International Year takes place 1895-Henryk Johan Bull's party makes the first confirmed landing on the Antarctic continent outside the Antarctic Peninsula 1902-Swedish explorer Otto Nordenskjold covers 400 mi. (644 km) in 33 days; British Discovery expedition to Antarctica is headed by Robert Falcon Scott and includes Ernest Shackleton 1904-66-South Georgia is home to the largest whaling station in the area 1908-The United Kingdom claims territory in Antarctica; Shackletonn leads an expedition to Antarctica 1909-Edgeworth David, Douglas Mawson, and Alistair Mackay reach the South Magnetic Pole 1911-Robert F Scott arrives at McMurdo Sound to establish a base camp from which to attempt to reach the South Pole; Amundsen arrives at the Bay of Whales to set out for the South Pole; Amundsen becomes the first person to reach the South Pole 1912-Robert F. Scott arrives at the South Pole; Scott and his four companions die on the return journey 1914-Sir Ernest Shackleton leads the Imperial Trans-Antarctic Expedition to Antarctica. 1915-Shackleton's ship, the Endurance, is crushed on the ice of the Weddell Sea 1916-Shackleton and five companions brave stormy seas to reach South Georgia to launch a rescue attempt of twenty-two expedition members stranded on Elephant Island 1923-New Zealand claims territory in Antarctica 1924-France claims territory in Antarctica 1928-The first plane flies over Antarctica; Richard Byrd leads a U.S. Antarctic expedition; Byrd establishes Little America Base, Bay of Whales 1932-33-The second International polar Year takes place 1933-Australia claims territory in Antarctica 1934-Byrd is the first person to spend a winter in the Antarctic interior, but nearly dies of carbon monoxide poisoning 1935-Ellsworth makes the first successful Trans-Antarctic flight; Caroline Mikkelsen is the first woman to step on the Antarctic continent; at the Vestfold Hils 1939-Norway claims territory in Antarctica 1940-Chile claims territory in Antarctica 1942-Argentina claims territory in Antarctica 1946-47-The United States navy conducts Operation Highjump with 4,700 men, 13 ships, and 23 airplanes to map extensive coastal areas using aerial photography 1947-Icebreakers are used for the first time in Antarctica; Edith Ronne and Jennie Darlington are the first women to live and work in Antarctica, spending nearly a year on Stonington Island near the Antarctic Peninsula 1955-Representatives from twelve nations, planning research in the Antarctic during International Geophysical Year (IGY), meet in Paris 1956-Airlines first fly tourist groups over the Antarctic Continent 1957-58-Twelve nations conduct research in Antarctica during the International Geophysical Year; The United States builds research facilities in Antarctica, including a large support station at McMurdo sound, Byrd Station in Marie Byrd Land, Ellsworth Station on the Filchner Ice Shelf, and the Amundsen-Scott South Pole Station; the Soviet Unioin builds a station at the Pole of Inaccessibility, the farthest point from all Antarctic coasts 1958-The first overland continental crossing is completed by Vivian Fuchs 1959-The Antarctic Treaty is signed by the twelve nations involved in Antarctic research during the IGY: Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, the United Kingdom, the United States and the Soviet Union 1961-The Antarctic Treaty enters into force 1967-Volcanic eruption starts on Deception Island (ends in 1970) 1979-An Air New Zealand DC-10 crashes into Mount Erebus, killing al 257 passengers and crew 1983-The lowest temperature ever recorded in Antarctica is taken at Vostok Station,-129° F. (-89.6° C) 1985-88- Construction work on the runway was halted due to protests. The runway crossed an important penguin breeding site. In 1989, the French Government resumed blasting and nearly wiped out a whole colony of penguins. 1987-British scientists first discover a 'hole' in the ozone layer over Antarctica 1990-The United Kingdom builds an airstrip at Rothera Station 1991-The treaty parties sign the Protocol on Environmental Protection to the Antarctic Treaty (part of the Antarctic Treaty System), designed to preserve the unique environment in Antarctica 1991-92-Approxamately 6,500 tourists visit Antarctica during the 1992-93 austral summer 1993-Geophysicists Donald Blankenship and Robin Bell discover evidence of several active volcanoes beneath the West Antarctic ice sheet; approximately 7,200 tourists visit Antarctica during the astral summer; in a joint effort by NASA and the United States Antarctic Program (USAP), Antarctica is selected as a test site for equipment destined for use on the moon and mars, NASA sends an eight-legged robot named Dante into Mount Erebus, an active volcano, Norwegian lawyer Erling Kagge becomes the first person to walk unaccompanied to the South Pole, making a 51-day, 814 mi. (1,310km) journey. 1994-The International Whaling Commission creates a sanctuary around Antarctica, putting nearly one quarter of the world's oceans off-limits to commercial whaling |
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References |
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Billings, Henry. Enchantment of the World - Antarctica. Children's Press: Chicago, 1994.
Hackwell, John W. Desert of Ice - Life and Work in Antarctica. Charles Scribner's Sons: New York, 1991. Hargreaves, Pat. Seas and Oceans - The Antarctic. Silver Burdette Company: Morristown, NJ, 1980. Johnson, Rebecca L. Braving the Frozen Frontier - Women Working in Antarctica. Lerner Publications Company: Minneapolis, 1997. Markle, Sandra. Pioneering Frozen Worlds. Atheneum Books for Young Readers: New York, 1996. Prevost, John F. Humpback Whales. ABDO & Daughters: Edina, MN, 1995. Pringle, Laurence. Antarctica - The Last Unspoiled Continent. Simon & Schuster: New York, 1992. Swan, Robert. Destination: Antarctica. Scholastic Inc.: New York, 1988. Williams, Lawrence. Last Frontiers for Mankind - Polar Lands. Marshall Cavendish Corporation: New York, 1990. Winckler, Suzanne and Mary M. Rodgers. Our Endangered Planet Antarctica. Lerner Publications Company: Minneapolis, 1992. Web sites: http://www.clearlight.com/~kid/whales/hbwhales.html http://quest.arc.nasa.gov/antarctica2/main/t_guide/blackline_2.html http://whales.magna.com.au/DISCOVER/gallery/index.html http://passport.ivv.nasa.gov/antarctica/teacherguide.html |
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ANTARCTIC OCEANOGRAPHY |
Executive Producer: Paula Coble, Ph.D. Graphics: Chad Edminsten Writers: Lori Huthmacher Kevin Jansen Rick Shine Edited by: Paula Coble Formatting: Juli Rasure Packet Distribution: Tracy Christner |
