Portal:Geography
The Geography Portal
Geography (from Ancient Greek γεωγραφία geōgraphía; combining gê 'Earth' and gráphō 'write') is the study of the lands, features, inhabitants, and phenomena of Earth. Geography is an all-encompassing discipline that seeks an understanding of Earth and its human and natural complexities—not merely where objects are, but also how they have changed and come to be. While geography is specific to Earth, many concepts can be applied more broadly to other celestial bodies in the field of planetary science. Geography has been called "a bridge between natural science and social science disciplines."
Origins of many of the concepts in geography can be traced to Greek Eratosthenes of Cyrene, who may have coined the term "geographia" (c. 276 BC – c. 195/194 BC). The first recorded use of the word γεωγραφία was as the title of a book by Greek scholar Claudius Ptolemy (100 – 170 AD). This work created the so-called "Ptolemaic tradition" of geography, which included "Ptolemaic cartographic theory." However, the concepts of geography (such as cartography) date back to the earliest attempts to understand the world spatially, with the earliest example of an attempted world map dating to the 9th century BCE in ancient Babylon. The history of geography as a discipline spans cultures and millennia, being independently developed by multiple groups and cross-pollinated by trade between these groups. The core concepts of geography consistent between all approaches are a focus on space, place, time and scale.
Today, geography is an extremely broad discipline with multiple approaches and modalities. There have been multiple attempts to organize the discipline, including the four traditions of geography, and into branches. Techniques employed can generally be broken down into quantitative and qualitative approaches, with many studies taking mixed-methods approaches. Common techniques include cartography, remote sensing, interviews and surveying. (Full article...)
Featured article -
Featured articles are displayed here, which represent some of the best content on English Wikipedia.
-
A map of Resolution Guyot's bathymetric relief
Resolution Guyot (formerly known as Huevo) is a guyot (tablemount) in the underwater Mid-Pacific Mountains in the Pacific Ocean. It is a circular flat mountain, rising 500 metres (1,600 ft) above the seafloor to a depth of about 1,320 metres (4,330 ft), with a 35-kilometre-wide (22-mile) summit platform. The Mid-Pacific Mountains lie west of Hawaii and northeast of the Marshall Islands, but at the time of its formation, the guyot was located in the Southern Hemisphere.
The guyot was probably formed by a hotspot in today's French Polynesia before plate tectonics shifted it to its present-day location. The Easter, Marquesas, Pitcairn and Society hotspots, among others, may have been involved in the formation of Resolution Guyot. Volcanic activity has been dated to have occurred 107–129 million years ago and formed a volcanic island that was subsequently flattened by erosion. Carbonate deposition commenced, forming an atoll-like structure and a carbonate platform. (Full article...) -
The Tang dynasty (/tɑːŋ/, [tʰǎŋ]; Chinese: 唐朝), or the Tang Empire, was an imperial dynasty of China that ruled from 618 to 907, with an interregnum between 690 and 705. It was preceded by the Sui dynasty and followed by the Five Dynasties and Ten Kingdoms period. Historians generally regard the Tang as a high point in Chinese civilisation, and a golden age of cosmopolitan culture. Tang territory, acquired through the military campaigns of its early rulers, rivalled that of the Han dynasty.
The Li family founded the dynasty after taking advantage of a period of Sui decline and precipitating their final collapse, in turn inaugurating a period of progress and stability in the first half of the dynasty's rule. The dynasty was formally interrupted during 690–705 when Empress Wu Zetian seized the throne, proclaiming the Wu Zhou dynasty and becoming the only legitimate Chinese empress regnant. The An Lushan rebellion (755–763) led to devastation and the decline of central authority during the latter half of the dynasty. Like the previous Sui dynasty, the Tang maintained a civil-service system by recruiting scholar-officials through standardised examinations and recommendations to office. The rise of regional military governors known as jiedushi during the 9th century undermined this civil order. The dynasty and central government went into decline by the latter half of the 9th century; agrarian rebellions resulted in mass population loss and displacement, widespread poverty, and further government dysfunction that ultimately ended the dynasty in 907. (Full article...)
Dom Pedro Afonso (19 July 1848 – 10 January 1850) was the Prince Imperial and heir apparent to the throne of the Empire of Brazil. Born at the Palace of São Cristóvão in Rio de Janeiro, he was the second son and youngest child of Emperor Dom Pedro II and Dona Teresa Cristina of the Two Sicilies, and thus a member of the Brazilian branch of the House of Braganza. Pedro Afonso was seen as vital to the future viability of the monarchy, which had been put in jeopardy by the death of his older brother Dom Afonso almost three years earlier.
Pedro Afonso's death from fever at the age of one devastated the Emperor, and the imperial couple had no further children. Pedro Afonso's older sister Dona Isabel became heiress, but Pedro II was unconvinced that a woman could ever be accepted as monarch by the ruling elite. He excluded Isabel from matters of state and failed to provide training for her possible role as empress. With no surviving male children, the Emperor came to understand that the imperial line was destined to end with his own death. (Full article...)
The Volcano, also known as Lava Fork volcano, is a small cinder cone in the Boundary Ranges of the Coast Mountains in northwestern British Columbia, Canada. It is located approximately 60 km (40 mi) northwest of the small community of Stewart near the head of Lava Fork. With a summit elevation of 1,656 m (5,433 ft) and a topographic prominence of 311 m (1,020 ft), it rises above the surrounding rugged landscape on a remote mountain ridge that represents the northern flank of a glaciated U-shaped valley.
Lava Fork volcano is associated with a small group of volcanoes called the Iskut volcanic field. This forms part of the much larger Northern Cordilleran Volcanic Province, which extends from the Alaska–Yukon border to near the port city of Prince Rupert, British Columbia. Eruptive activity at The Volcano is relatively young compared to most other volcanoes in the Northern Cordilleran Volcanic Province. Geologic studies have shown that The Volcano and its eruptive products were emplaced in the last 400 years; this is well after the last glacial period, which ended about 10,000 years ago. (Full article...)
The peregrine falcon (Falco peregrinus), also known simply as the peregrine, is a cosmopolitan bird of prey (raptor) in the family Falconidae. A large, crow-sized falcon, it has a blue-grey back, barred white underparts, and a black head. The peregrine is renowned for its speed. It can reach over 320 km/h (200 mph) during its characteristic hunting stoop (high-speed dive), making it the fastest animal on the planet. According to a National Geographic TV program, the highest measured speed of a peregrine falcon is 389 km/h (242 mph). However, radar tracks have never confirmed this, the maximum speed reliably measured is 184 km/h (114 mph), but nobody has been able to present unimpeachable measurements of speeds even close to the "well-known" 300 km/h (190 mph). As is typical for bird-eating (avivore) raptors, peregrine falcons are sexually dimorphic, with females being considerably larger than males. Historically, it has also been known as "black-cheeked falcon" in Australia, and "duck hawk" in North America.
The breeding range includes land regions from the Arctic tundra to the tropics. It can be found nearly everywhere on Earth, except extreme polar regions, very high mountains, and most tropical rainforests; the only major ice-free landmass from which it is entirely absent is New Zealand. This makes it the world's most widespread raptor and one of the most widely found wild bird species. In fact, the only land-based bird species found over a larger geographic area owes its success to human-led introduction; the domestic and feral pigeons are both domesticated forms of the rock dove, a major prey species for Eurasian Peregrine populations. Due to their abundance over most other bird species in cities, feral pigeons support many peregrine populations as a staple food source, especially in urban settings. (Full article...)
The Rashtrakutas were a royal Indian dynasty ruling large parts of the Indian subcontinent between the 6th and 10th centuries. The earliest known Rashtrakuta inscription is a 7th-century copper plate grant detailing their rule from Manapur, a city in Central or West India. Other ruling Rashtrakuta clans from the same period mentioned in inscriptions were the kings of Achalapur and the rulers of Kannauj. Several controversies exist regarding the origin of these early Rashtrakutas, their native homeland and their language.
The Elichpur clan was a feudatory of the Badami Chalukyas, and during the rule of Dantidurga, it overthrew Chalukya Kirtivarman II and went on to build an empire with the Gulbarga region in modern Karnataka as its base. This clan came to be known as the Rashtrakutas of Manyakheta, rising to power in South India in 753 AD. At the same time the Pala dynasty of Bengal and the Prathihara dynasty of Gurjaratra were gaining force in eastern and northwestern India respectively. An Arabic text, Silsilat al-Tawarikh (851), called the Rashtrakutas one of the four principal empires of the world. (Full article...)
.svg)
Antarctica (/ænˈtɑːrktɪkə/ ) is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of 14,200,000 km (5,500,000 sq mi). Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of 1.9 km (1.2 mi).
Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over 200 mm (8 in) along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost 60 metres (200 ft). Antarctica holds the record for the lowest measured temperature on Earth, −89.2 °C (−128.6 °F). The coastal regions can reach temperatures over 10 °C (50 °F) in the summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where vegetation occurs, it is mostly in the form of lichen or moss. (Full article...)
The surrender of the Empire of Japan in World War II was announced by Emperor Hirohito on 15 August and formally signed on 2 September 1945, ending the war. By the end of July 1945, the Imperial Japanese Navy (IJN) was incapable of conducting major operations and an Allied invasion of Japan was imminent. Together with the United Kingdom and China, the United States called for the unconditional surrender of Japan in the Potsdam Declaration on 26 July 1945—the alternative being "prompt and utter destruction". While publicly stating their intent to fight on to the bitter end, Japan's leaders (the Supreme Council for the Direction of the War, also known as the "Big Six") were privately making entreaties to the publicly neutral Soviet Union to mediate peace on terms more favorable to the Japanese. While maintaining a sufficient level of diplomatic engagement with the Japanese to give them the impression they might be willing to mediate, the Soviets were covertly preparing to attack Japanese forces in Manchuria and Korea (in addition to South Sakhalin and the Kuril Islands) in fulfillment of promises they had secretly made to the US and the UK at the Tehran and Yalta Conferences.
On 6 August 1945, at 8:15 am local time, the United States detonated an atomic bomb over the Japanese city of Hiroshima. Sixteen hours later, American President Harry S. Truman called again for Japan's surrender, warning them to "expect a rain of ruin from the air, the like of which has never been seen on this earth." Late on 8 August 1945, in accordance with the Yalta agreements, but in violation of the Soviet–Japanese Neutrality Pact, the Soviet Union declared war on Japan, and soon after midnight on 9 August 1945, the Soviet Union invaded the Japanese puppet state of Manchukuo. Hours later, the United States dropped a second atomic bomb, on the Japanese city of Nagasaki. Emperor Hirohito ordered the Supreme Council for the Direction of the War to accept the terms the Allies had set down in the Potsdam Declaration. After several more days of behind-the-scenes negotiations and a failed coup d'état, Emperor Hirohito gave a recorded radio address across the Empire on 15 August announcing the surrender of Japan to the Allies. (Full article...)
The Mount Cayley volcanic field (MCVF) is a remote volcanic zone on the South Coast of British Columbia, Canada, stretching 31 km (19 mi) from the Pemberton Icefield to the Squamish River. It forms a segment of the Garibaldi Volcanic Belt, the Canadian portion of the Cascade Volcanic Arc, which extends from Northern California to southwestern British Columbia. Most of the MCVF volcanoes were formed during periods of volcanism under sheets of glacial ice throughout the last glacial period. These subglacial eruptions formed steep, flat-topped volcanoes and subglacial lava domes, most of which have been entirely exposed by deglaciation. However, at least two volcanoes predate the last glacial period and both are highly eroded. The field gets its name from Mount Cayley, a volcanic peak located at the southern end of the Powder Mountain Icefield. This icefield covers much of the central portion of the volcanic field and is one of the several glacial fields in the Pacific Ranges of the Coast Mountains.
Eruptions along the length of the MCVF began between 1.6 and 5.3 million years ago. At least 23 eruptions have occurred throughout its eruptive history. This volcanic activity ranged from effusive to explosive, with magma compositions ranging from basaltic to rhyolitic. Because the MCVF has a high elevation and consists of a cluster of mostly high altitude, non-overlapping volcanoes, subglacial activity is likely to have occurred under less than 800 m (2,600 ft) of glacial ice. The style of this glaciation promoted meltwater escape during eruptions. The steep profile of the volcanic field and its subglacial landforms support this hypothesis. As a result, volcanic features in the MCVF that interacted with glacial ice lack rocks that display evidence of abundant water during eruption, such as hyaloclastite and pillow lava. (Full article...)
.jpg)
Horizon Guyot is a presumably Cretaceous guyot (tablemount) in the Mid-Pacific Mountains, Pacific Ocean. It is an elongated ridge, over 300 kilometres (190 mi) long and 4.3 kilometres (2.7 mi) high, that stretches in a northeast–southwest direction and has two flat tops; it rises to a minimum depth of 1,443 metres (4,730 ft). The Mid-Pacific Mountains lie west of Hawaii and northeast of the Line Islands.
It was probably formed by a hotspot, but the evidence is conflicting. Volcanic activity occurred during the Turonian-Cenomanian eras 100.5–89.8 million years ago and another stage has been dated to have occurred 88–82 million years ago. Between these volcanic episodes, carbonate deposition from lagoonal and reefal environments set in and formed limestone. Volcanic islands developed on Horizon Guyot as well and were colonised by plants. (Full article...)
SMS Weissenburg was one of the first ocean-going battleships of the Imperial German Navy. She was the third pre-dreadnought of the Brandenburg class, which also included her sister ships Brandenburg, Wörth, and Kurfürst Friedrich Wilhelm. Weissenburg was laid down in 1890 in the AG Vulcan dockyard in Stettin, launched in 1891, and completed in 1894. The Brandenburg-class battleships were unique for their era in that they carried six large-caliber guns in three twin turrets, as opposed to four guns in two turrets, as was the standard in other navies.
Weissenburg served with I Division during the first decade of her service with the fleet. This period was generally limited to training exercises and goodwill visits to foreign ports. These training maneuvers were nevertheless very important to developing German naval tactical doctrine in the two decades before World War I, especially under the direction of Alfred von Tirpitz. Weissenburg, along with her three sisters, saw only one major overseas deployment during this period, to China in 1900–1901, during the Boxer Uprising. The ship underwent a major modernization in 1904–1905. (Full article...)
_without_New_Guinea.svg)
