Physical geography (also known as geosystems or physiography) is one of the two major sub-fields of geography. Physical geography is that branch of natural science which deals with the study of processes and patterns in the natural environment like the atmosphere, hydrosphere, biosphere, and geosphere, as opposed to the cultural or built environment, the domain of human geography.
Within the body of physical geography, the Earth is often split either into several spheres or environments, the main spheres being the atmosphere, biosphere, cryosphere, geosphere, hydrosphere, lithosphere and pedosphere. Research in physical geography is often interdisciplinary and uses the systems approach.
Political geography is the field of human geography that is concerned with the study of both the spatially uneven outcomes of political processes and the ways in which political processes are themselves affected by spatial structures. Conventionally political geography adopts a three-scale structure for the purposes of analysis with the study of the state at the centre, above this is the study of international relations (or geopolitics), and below it is the study of localities. The primary concerns of the sub-discipline can be summarised as the inter-relationships between people, state, and territory.
"Political geography in essence builds a country economy" The origins of political geography lie in the origins of human geography itself and the early practitioners were concerned mainly with the military and political consequences of the relationships between physical geography, state territories, and state power. In particular there was a close association with regional geography, with its focus on the unique characteristics of regions, and environmental determinism with its emphasis on the influence of the physical environment on human activities. This association found expression in the work of the German geographer Friedrich Ratzel who, in 1897 in his book Politische Geographie, developed the concept of Lebensraum (living space) which explicitly linked the cultural growth of a nation with territorial expansion, and which was later used to provide academic legitimation for the imperialist expansion of the German Third Reich in the 1930s.
This is a list of extreme points of Earth, the points that are farther north, south, east or west than, higher or lower in altitude than, or farthest inland or out to sea from, any other locations on the landmasses, continents or countries.
Flightless birds are birds that cannot fly but they can run and/or swim instead of flying, but they did evolve from flying ancestors. There are about 40 species in existence today, the best known being the ratites (ostrich, emu, cassowary, rhea and kiwi) and the penguins. Some birds evolved flightlessness in response to the release from predation, for example on oceanic islands, although this is likely not the case for the ratites as evolutionary origins suggest a continental biogeographical providence.]citation needed[
Two key differences between flying and flightless birds are the smaller wing bones of flightless birds and the absent (or greatly reduced) keel on their breastbone. (The keel anchors muscles needed for wing movement.) Flightless birds also have more feathers than flying birds.
The geography of Antarctica is dominated by its south polar location and, thus, by ice. The Antarctic continent, located in the Earth's southern hemisphere, is centered asymmetrically around the South Pole and largely south of the Antarctic Circle. It is surrounded by the southern waters of the World Ocean – alternatively (depending on source), it is washed by the Southern (or Antarctic) Ocean or the southern Pacific, Atlantic, and Indian Oceans. It has an area of more than 14 million km².
Some 98% of Antarctica is covered by the Antarctic ice sheet, the world's largest ice sheet and also its largest reservoir of fresh water. Averaging at least 1.6 km thick, the ice is so massive that it has depressed the continental bedrock in some areas more than 2.5 km below sea level; subglacial lakes of liquid water also occur (e.g., Lake Vostok). Ice shelves and rises populate the ice sheet on the periphery. Only about 2% of the continent is not covered by ice.
The polar bear (Ursus maritimus) is a carnivorous bear whose native range lies largely within the Arctic Circle, encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is a large bear, approximately the same size as the omnivorous Kodiak bear (Ursus arctos middendorffi). A boar (adult male) weighs around 350–700 kg (770–1,500 lb), while a sow (adult female) is about half that size. Although it is the sister species of the brown bear, it has evolved to occupy a narrower ecological niche, with many body characteristics adapted for cold temperatures, for moving across snow, ice, and open water, and for hunting the seals which make up most of its diet. Although most polar bears are born on land, they spend most of their time at sea. Their scientific name means "maritime bear", and derives from this fact. Polar bears hunt their preferred food of seals from the edge of sea ice, often living off fat reserves when no sea ice is present.
The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is, subject to the caveats explained below, defined as the point in the Northern Hemisphere where the Earth's axis of rotation meets its surface. It should not be confused with the North Magnetic Pole.
The South Pole, also known as the Geographic South Pole or Terrestrial South Pole, is one of the two points where the Earth's axis of rotation intersects its surface. It is the southernmost point on the surface of the Earth and lies on the opposite side of the Earth from the North Pole. Situated on the continent of Antarctica, it is the site of the United States Amundsen-Scott South Pole Station, which was established in 1956 and has been permanently staffed since that year. The Geographic South Pole should not be confused with the South Magnetic Pole, which though geographically nearby, is defined based on the Earth's magnetic field.
The Polar Challenge is a competitive, 350 nautical mile (650 kilometer) team race taking place in the Arctic, to the 1996 location of the Magnetic North Pole. The race runs between mid-April and mid-May each year, taking teams approximately 4 weeks to complete, including the training time. This event should not be confused with the Polar Race, which is a different event taking a different route, and run by a different organisation.
Competitors race in teams of 3, many joining as individuals and forming teams when they meet other individuals during the training that leads up to the race. The competitors are from different walks of life (not necessarily explorers or people with mountaineering experience), sharing a quest for adventure and to achieve something that only a few others have done. The race takes place in one of the world's most extreme and hostile environments, with temperatures dropping as low as -35 °C, and where 80% of the world’s population of Polar Bears live. Competitors race on skis, pulling their supplies in 120 lb pulkas, stopping on route at 3 manned checkpoints to re-supply.
Frozen Planet is a nature documentary series, co-produced by the BBC, the Discovery Channel and The Open University. It was filmed by the BBC Natural History Unit. Other production partners are the Discovery Channel Canada, ZDF (Germany), Antena 3 (Spain) and Skai TV (Greece). The production team, which includes executive producer Alastair Fothergill and series producer Vanessa Berlowitz, were previously responsible for the award-winning series The Blue Planet (2001) and Planet Earth (2006), and Frozen Planet is billed as a sequel of sorts.]citation needed[ David Attenborough returns as narrator.
The seven-part series focuses on life and the environment in both the Arctic and Antarctic. The production team were keen to film a comprehensive record of the natural history of the polar regions because climate change is affecting landforms such as glaciers, ice shelves, and the extent of sea ice. The film was met with critical acclaim and holds a Metacritic score of 90/100. Despite such, it has been criticized for limited coverage of the effects of global warming and attribution of recent climate change.