Antarctica
Physical geography
The Antarctic continent is located near the South Pole and covers most of the Southern Hemisphere. Its size varies greatly depending on how it is defined. If one considers only the ice-covered land area, the total land mass of Antarctica is approximately 7.2 million square kilometers (2.8 million square miles). This includes all of the islands, bays, peninsulas, glaciers, and ice shelves within the continent’s boundaries. However, because there are no permanent human settlements in Antarctica, the true landmass cannot be determined without including the sea areas covered by ice sheets and glaciers. In fact, according to the United Nations Environment Programme (UNEP), the world’s largest island, Greenland, is larger than Antarctica.
Geologically speaking, the Antarctic region consists of a large number of tectonic plates that are slowly moving away from each other. These include the African Plate, Indian Ocean Plate, Pacific Plate, Scotia Plate, and Antarctic Plate. The movement of these plates causes the formation of mountains, volcanoes, earthquakes, and rifts.
Antarctica is part of the Pangaea supercontinent, which existed during the Paleozoic era. During this period, the Earth consisted of a single gigantic landmass called Gondwana, which included what are now Africa, India, Australia, Antarctica, South America,
Structural framework
The Antarctic Peninsula is the most accessible part of Antarctica, and it is where most of our current understanding of the continent’s geology originates. Geologists have recognized that the peninsula consists of three major tectonic domains separated by active faults: the Ross Sea domain, the Weddell Sea domain, and the Amundsen Basin domain.
These domains are divided by the Transantarctic Mountain Belt, a zone of mostly Miocene rocks that extends along the western margin of the peninsula. This structure includes the Shackleton Range and the Gamburtsev Range, both of which extend southward from the Transantarctic mountains toward the ocean.
In addition to the Transantarctic mountain belt, there is another prominent feature in the southern portion of the peninsula: the Amundsen Basin, named after Roald Amundsen, whose 1911–13 expedition discovered the South Pole. The basin contains several large volcanoes, including Mount Erebus, Mount Terror, Mount Melbourne, and Mount Keppler.
Geologically speaking, the Amundsen Basin is a rift valley formed during the break-up of Rodinia, a supercontinent that existed about 600 million years ago.
The rift valley is bounded by the Transantarctics on the north and the Transantarctic Convergence Zone on the south. In contrast to the relatively flat plateau of the Ross Sea domain, which is composed of older Paleoproterozoic sedimentary rocks, the Amundsen basin is characterized by steep cliffs and deep valleys filled with volcanic rock.
Most of the Antarctic Peninsula’s geologic history occurred during the breakup of Rodinia, but some events took place earlier. Early orogenesis occurred in the Cambrian Period, about 500 million years ago, when the crustal blocks that later became the Transantarctical Mountains collided against the edge of Rodinia.
During the late Neoproterozoic Era, about 2 billion years ago, the collision process continued, resulting in the formation of the Transantarctica Mountains. These mountains continue to grow today, although the rate of growth has slowed considerably since the end of the Neoproterozoian period.
Exploring Antarctica
The frozen southern continent wasn’t spotted until 1820. American seal hunter John Davis claimed he landed on Antarctica in January 1821, though some historians dispute his claim, saying he didn’t land there until 1822.
At the beginning of the 20 th century, two groups of adventurers set out across the desolate landscape in a race to reach the South Pole. One group was led by Norwegian explorer R oald Amundsen, while the other consisted of British naval officer Robert Falcon Scott.
Amundsen and his men spent 99 days racing one-another to the pole, reaching it on December 14, 1912, while Scott and his party arrived four weeks later, on January 17, 1913. But neither group made it home alive.
Scott and his team perished during a blizzard on Feb. 23, 1912; Amundsen died on his return trip to Norway in June 1914.
When to see
The Antarctic Peninsula is one of the best places to go during the Antarctic winter because it does not experience much change in weather. There are no extreme temperatures, and there is almost always enough daylight to take photos. In addition, you can travel to some of the most remote locations.
This season, the peninsula is covered with snow and ice, and there is still plenty of light. However, the sun sets earlier than usual, and the days become shorter. By mid-November, the sun barely rises above the horizon, and the temperature drops to -50 degrees Celsius (-58 degrees Fahrenheit).
In December, the sun returns to Antarctica, and the sky turns blue again. In January, the sun never goes down, and the temperature reaches +10 degrees Celsius (+14 degrees Fahrenheit), making it the warmest month of the year.
Penguins
Antarctica’s Adélie penguins are some of the most sociable birds on Earth. They live in large groups called colonies, where hundreds of penguins nest together in close proximity. During the Antarctic winter, the colony members congregate around a nearby ice sheet, waiting for the sun to return each day. As soon as it does, they head out onto the sea ice to hunt seals.
In December, the penguins start building nests, laying eggs and raising their young. At the end of the month, the adults go away for a couple of weeks while the chicks hatch. Then the parents return to feed them.
The Adélies are one of the few species of penguin that don’t migrate. Instead, they spend the entire winter season on land.
Whale watching
The Antarctic Ocean is home to hundreds of different kinds of whales, including killer whales, blue whales, humpback whales, orcas and others. While it’s possible to see some of those animals during the winter months, the best time to view them is during the summer season. Whale watching tours allow visitors to experience the beauty of nature up close.
During the summer, Antarctic waters become full of many different types whales looking to eat fish and squid, along with penguins and plankton, according to National Geographic. Killer whales are one of the most common whale species you could encounter while traveling around Antarctica. They are known for hunting seals and penguins, and they often swim alongside boats to check out what humans are doing.
Seal pups
Antarctic waters are rich with wedells, crabeaters, leopards, fur and elephant seals, many of which are protected under international law. Fur seal pups are usually born mid-November to early December. They are nursed for five to eight days and then visited every few days for four months before being completely weaned in March or April.
The International Union for Conservation of Nature lists Weddell Seal as vulnerable. Crabeater Seal is listed as endangered. Both species are found along Antarctica’s coastlines and islands. Elephant Seals are classified as vulnerable. Leopard Seals are listed as near threatened. Fur Seals are listed as least concern.
