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Topic Review

Artificial Island

An artificial island or man-made island is an island that has been constructed by people rather than formed by natural means. Artificial islands may vary in size from small islets reclaimed solely to support a single pillar of a building or structure, to those that support entire communities and cities. Early artificial islands included floating structures in still waters, or wooden or megalithic structures erected in shallow waters (e.g. crannógs and Nan Madol discussed below). In modern times artificial islands are usually formed by land reclamation, but some are formed by the incidental isolation of an existing piece of land during canal construction (e.g. Donauinsel, Ko Kret, and much of Door County), or flooding of valleys resulting in the tops of former knolls getting isolated by water (e.g. Barro Colorado Island). One of the world's largest artificial islands, René-Levasseur Island, was formed by the flooding of two adjacent reservoirs.

4.6K
11 Oct 2022

Topic Review

Floating Island

A floating island is a mass of floating aquatic plants, mud, and peat ranging in thickness from several centimeters to a few meters. Floating islands are a common natural phenomenon that are found in many parts of the world. They exist less commonly as an artificial phenomenon. Floating islands are generally found on marshlands, lakes, and similar wetland locations, and can be many hectares in size.

4.6K
21 Oct 2022

Topic Review

Terminology of the British Isles

The terminology of the British Isles refers to the various words and phrases that are used to describe the different (and sometimes overlapping) geographical and political areas of the islands of Great Britain, Ireland, and the smaller islands which surround them. The terminology is often a source of confusion, partly owing to the similarity between some of the actual words used, but also because they are often used loosely. In addition, many of the words carry both geographical and political connotations which are affected by the history of the islands. The purpose of this article is to explain the meanings of and relationships among the terms in use; however many of these classifications are contentious and are the subject of disagreement (See the British Isles naming dispute).

4.6K
03 Nov 2022

Topic Review

Gaia Hypothesis

The Gaia hypothesis (/ˈɡaɪ.ə/), also known as the Gaia theory, Gaia paradigm, or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet. The hypothesis was formulated by the chemist James Lovelock and co-developed by the microbiologist Lynn Margulis in the 1970s. Lovelock named the idea after Gaia, the primordial goddess who personified the Earth in Greek mythology. The suggestion that the theory should be called "the Gaia hypothesis" came from Lovelock's neighbour, William Golding. In 2006, the Geological Society of London awarded Lovelock the Wollaston Medal in part for his work on the Gaia hypothesis. Topics related to the hypothesis include how the biosphere and the evolution of organisms affect the stability of global temperature, salinity of seawater, atmospheric oxygen levels, the maintenance of a hydrosphere of liquid water and other environmental variables that affect the habitability of Earth. The Gaia hypothesis was initially criticized for being teleological and against the principles of natural selection, but later refinements aligned the Gaia hypothesis with ideas from fields such as Earth system science, biogeochemistry and systems ecology. Even so, the Gaia hypothesis continues to attract criticism, and today many scientists consider it to be only weakly supported by, or at odds with, the available evidence.

4.5K
07 Nov 2022

Topic Review

Nicaea or Nicea (/naɪˈsiːə/; Greek: Νίκαια, Níkaia; Turkish: İznik) was an ancient city in northwestern Anatolia, and is primarily known as the site of the First and Second Councils of Nicaea (the first and seventh Ecumenical councils in the early history of the Christian Church), the Nicene Creed (which comes from the First Council), and as the capital city of the Empire of Nicaea following the Fourth Crusade in 1204, until the recapture of Constantinople by the Byzantines in 1261. The ancient city is located within the modern Turkish city of İznik (whose modern name derives from Nicaea's), and is situated in a fertile basin at the eastern end of Lake Ascanius, bounded by ranges of hills to the north and south. It is situated with its west wall rising from the lake itself, providing both protection from siege from that direction, as well as a source of supplies which would be difficult to cut off. The lake is large enough that it could not be blockaded from the land easily, and the city was large enough to make any attempt to reach the harbour from shore-based siege weapons very difficult. The ancient city is surrounded on all sides by 5 kilometres (3 mi) of walls about 10 metres (33 ft) high. These are in turn surrounded by a double ditch on the land portions, and also included over 100 towers in various locations. Large gates on the three landbound sides of the walls provided the only entrance to the city. Today the walls have been pierced in many places for roads, but much of the early work survives and, as a result, it is a major tourist destination.

4.3K
08 Nov 2022

Topic Review

Scottish Highlands

The Highlands (Scots: the Hielands; Scottish Gaelic: a’ Ghàidhealtachd [ə ˈɣɛːəl̪ˠt̪ʰəxk], 'the place of the Gaels') is a historical region of Scotland. Culturally, the Highlands and the Lowlands diverged from the Late Middle Ages into the modern period, when Lowland Scots replaced Scottish Gaelic throughout most of the Lowlands. The term is also used for the area north and west of the Highland Boundary Fault, although the exact boundaries are not clearly defined, particularly to the east. The Great Glen divides the Grampian Mountains to the southeast from the Northwest Highlands. The Scottish Gaelic name of A' Ghàidhealtachd literally means "the place of the Gaels" and traditionally, from a Gaelic-speaking point of view, includes both the Western Isles and the Highlands.The area is very sparsely populated, with many mountain ranges dominating the region, and includes the highest mountain in the British Isles, Ben Nevis. During the 18th and early 19th centuries the population of the Highlands rose to around 300,000, but from c. 1841 and for the next 160 years, the natural increase in population was exceeded by emigration (mostly to Canada, the United States, Australia and New Zealand, and migration to the industrial cities of Scotland and England.):xxiii, 414 and passim The area is now one of the most sparsely populated in Europe. At 9.1/km2 (24/sq mi) in 2012, the population density in the Highlands and Islands is less than one seventh of Scotland's as a whole, comparable with that of Bolivia, Chad and Russia . The Highland Council is the administrative body for much of the Highlands, with its administrative centre at Inverness. However, the Highlands also includes parts of the council areas of Aberdeenshire, Angus, Argyll and Bute, Moray, North Ayrshire, Perth and Kinross, Stirling and West Dunbartonshire. The Scottish Highlands is the only area in the British Isles to have the taiga biome as it features concentrated populations of Scots pine forest: see Caledonian Forest. It is the most mountainous part of the United Kingdom .

4.1K
30 Nov 2022

Topic Review

Pedogenesis (from the Greek pedo-, or pedon, meaning 'soil, earth,' and genesis, meaning 'origin, birth') (also termed soil development, soil evolution, soil formation, and soil genesis) is the process of soil formation as regulated by the effects of place, environment, and history. Biogeochemical processes act to both create and destroy order (anisotropy) within soils. These alterations lead to the development of layers, termed soil horizons, distinguished by differences in color, structure, texture, and chemistry. These features occur in patterns of soil type distribution, forming in response to differences in soil forming factors. Pedogenesis is studied as a branch of pedology, the study of soil in its natural environment. Other branches of pedology are the study of soil morphology, and soil classification. The study of pedogenesis is important to understanding soil distribution patterns in current (soil geography) and past (paleopedology) geologic periods.

4.0K
03 Nov 2022

Topic Review

Maritime Southeast Asia

Maritime Southeast Asia comprises the countries of Brunei, East Timor, Indonesia, Malaysia, the Philippines and Singapore. Maritime Southeast Asia is sometimes also referred to as Island Southeast Asia, Insular Southeast Asia or Oceanic Southeast Asia. The 16th-century term "East Indies" and the later 19th-century term "Malay Archipelago" are also used to refer to Maritime Southeast Asia. In Indonesia and Malaysia, the Old Javanese term "Nusantara" is also used as a synonym for Maritime Southeast Asia. The term, however, is nationalistic and has shifting boundaries. It usually only encompasses the Malay Peninsula, the Sunda Islands, Maluku, and often Western New Guinea and excludes the Philippines . Stretching for several thousand kilometres, the area features a very large number of islands and boasts some of the richest marine, flora and fauna biodiversity on Earth. The main demographic difference that sets Maritime Southeast Asia apart from modern Mainland Southeast Asia is that its population predominantly belongs to Austronesian groups. The region contains some of the world's most highly urbanized areas—Greater Jakarta, Greater Kuala Lumpur, Metro Manila, and Singapore—and yet a majority of islands in this vast region remain uninhabited by humans.

4.0K
28 Nov 2022

Topic Review

Restrictions on Geographic Data in China

Due to national security concerns, the use of geographic information in China is restricted to entities that obtain a special authorization from the administrative department for surveying and mapping under the State Council. Consequences of the restriction include fines for unauthorized surveys, lack of geotagging information on many cameras when the GPS chip detects a location within China, incorrect alignment of street maps with satellite maps in various applications, and seeming unlawfulness of crowdsourced mapping efforts such as OpenStreetMap.

4.0K
25 Nov 2022

Topic Review

Built-In Car Navigation System

Driving is based on effective navigation. When using a navigation device, the user interface, the amount and quality of the underlying data and its representation all effect the quality of navigation. This study evaluates whether drivers in three different countries consider these devices to be useful and what functionality they would prefer. An online questionnaire was used to assess built-in navigation systems. The findings from 213 respondents show that current car GPSs are overloaded with features. Regardless of country, drivers simply require more basic functionality in the interface. It was also noted that the embedded functions in these devices are not fully utilized. In addition, many people use the navigation service to enter a new address while the car is moving. It may be worth examining how this option can be better implemented.

3.9K
10 May 2022

Topic Review

A deserted island or uninhabited island is an island that is not permanently populated by humans. Uninhabited islands are often used in movies or stories about shipwrecked people, and are also used as stereotypes for the idea of "paradise". Some uninhabited islands are protected as nature reserves and some are privately owned. Devon Island in Canada is claimed to be the largest uninhabited island in the world. Small coral atolls or islands usually have no source of fresh water, but at times a fresh water lens (Ghyben–Herzberg lens) can be reached with a well.

3.7K
14 Oct 2022

Topic Review

Hauran (Arabic: حوران / ALA-LC: Ḥawrān), also spelled Hawran, Houran and Horan, known to the Ancient Greeks and Romans as Auranitis, is a volcanic plateau, a geographic area and a people located in southwestern Syria and extending into the northwestern corner of Jordan, it’s known to be the birth place of the dabke dance which is the most popular dance in all of the Levant.

3.7K
10 Nov 2022

Topic Review

Pine Ridge Indian Reservation

The Pine Ridge Indian Reservation (Template:Lang-lkt), also called Pine Ridge Agency, is an Oglala Lakota Native American reservation located in the U.S. state of South Dakota. Originally included within the territory of the Great Sioux Reservation, Pine Ridge was created by the Act of March 2, 1889, 25 Stat. 888. in the southwest corner of South Dakota on the Nebraska border. Today it consists of 3,468.85 sq mi (8,984.3 km2) of land area and is the eighth-largest reservation in the United States, larger than Delaware and Rhode Island combined. The reservation encompasses the entirety of Oglala Lakota County and Bennett County, the southern half of Jackson County, and a small section of Sheridan County added by Executive Order No. 2980 of February 20, 1904. Of the 3,142 counties in the United States, these are among the poorest. Only 84,000 acres (340 km2) of land are suitable for agriculture. The 2000 census population of the reservation was 15,521; but a study conducted by Colorado State University and accepted by the United States Department of Housing and Urban Development has estimated the resident population to reach 28,787. Pine Ridge is the site of several events that mark milestones in the history between the Sioux of the area and the United States (U.S.) government. Stronghold Table—a mesa in what is today the Oglala-administered portion of Badlands National Park—was the location of the last of the Ghost Dances. The U.S. authorities' attempt to repress this movement eventually led to the Wounded Knee Massacre on December 29, 1890. A mixed band of Miniconjou Lakota and Hunkpapa Sioux, led by Chief Spotted Elk, sought sanctuary at Pine Ridge after fleeing the Standing Rock Agency, where Sitting Bull had been killed during efforts to arrest him. The families were intercepted by a heavily armed detachment of the Seventh Cavalry, which attacked them, killing many women and children as well as warriors. This was the last large engagement between U.S. forces and Native Americans and marked the end of the western frontier. Changes accumulated in the last quarter of the 20th century; in 1971 the Oglala Sioux Tribe (OST) started Oglala Lakota College, a tribal college, which offers 4-year degrees. In 1973 decades of discontent at the Pine Ridge Reservation resulted in a grassroots protest that escalated into the Wounded Knee Incident, gaining national attention. Members of the Oglala Lakota, the American Indian Movement and supporters occupied the town in defiance of federal and state law enforcement in a protest that turned into an armed standoff lasting 71 days. This event inspired American Indians across the country and gradually led to changes at the reservation, with a revival of some cultural traditions. In 1981 the Lakota Tim Giago started the Lakota Times at Pine Ridge, the first independent Native American newspaper in the nation; he published it until selling it in 1998. Located at the southern end of the Badlands, the reservation is part of the mixed grass prairie, an ecological transition zone between the short-grass and tall-grass prairies; all are part of the Great Plains. A great variety of plant and animal life flourishes on and adjacent to the reservation, including the endangered black-footed ferret. The area is also important in the field of paleontology; it contains deposits of Pierre Shale formed on the seafloor of the Western Interior Seaway, evidence of the marine Cretaceous–Paleogene boundary, and one of the largest deposits of fossils of extinct mammals from the Oligocene epoch.

3.7K
07 Oct 2022

Topic Review

Rank-Size Distribution

Rank-size distribution is the distribution of size by rank, in decreasing order of size. For example, if a data set consists of items of sizes 5, 100, 5, and 8, the rank-size distribution is 100, 8, 5, 5 (ranks 1 through 4). This is also known as the rank-frequency distribution, when the source data are from a frequency distribution. These are particularly of interest when the data vary significantly in scale, such as city size or word frequency. These distributions frequently follow a power law distribution, or less well-known ones such as a stretched exponential function or parabolic fractal distribution, at least approximately for certain ranges of ranks; see below. A rank-size distribution is not a probability distribution or cumulative distribution function. Rather, it is a discrete form of a quantile function (inverse cumulative distribution) in reverse order, giving the size of the element at a given rank.

3.7K
31 Oct 2022

Topic Review

Frame of Reference

In physics, a frame of reference (or reference frame) consists of an abstract coordinate system and the set of physical reference points that uniquely fix (locate and orient) the coordinate system and standardize measurements within that frame. For n dimensions, n + 1 reference points are sufficient to fully define a reference frame. Using rectangular (Cartesian) coordinates, a reference frame may be defined with a reference point at the origin and a reference point at one unit distance along each of the n coordinate axes. In Einsteinian relativity, reference frames are used to specify the relationship between a moving observer and the phenomenon or phenomena under observation. In this context, the phrase often becomes "observational frame of reference" (or "observational reference frame"), which implies that the observer is at rest in the frame, although not necessarily located at its origin. A relativistic reference frame includes (or implies) the coordinate time, which does not correspond across different frames moving relatively to each other. The situation thus differs from Galilean relativity, where all possible coordinate times are essentially equivalent.

3.5K
21 Oct 2022

Topic Review

Mercury's Magnetic Field

Mercury's magnetic field is approximately a magnetic dipole (meaning the field has only two magnetic poles) apparently global, on planet Mercury. Data from Mariner 10 led to its discovery in 1974; the spacecraft measured the field's strength as 1.1% that of Earth's magnetic field. The origin of the magnetic field can be explained by dynamo theory. The magnetic field is strong enough near the bow shock to slow the solar wind, which induces a magnetosphere.

3.4K
15 Nov 2022

Topic Review

Middle Eastern Philosophy

Middle Eastern philosophy includes the various philosophies of the Middle East regions, including the Fertile Crescent, Iran, and Anatolia. Traditions include Ancient Egyptian philosophy, Babylonian philosophy, Jewish philosophy, Iranian/Persian philosophy, and Islamic philosophy.

3.4K
05 Dec 2022

Topic Review

French Geodesic Mission

The French Geodesic Mission (also called the Geodesic Mission to Peru, Geodesic Mission to the Equator and the Spanish-French Geodesic Mission) was an 18th-century expedition to what is now Ecuador carried out for the purpose of measuring the roundness of the Earth and measuring the length of a degree of latitude at the Equator. The mission was one of the first geodesic (or geodetic) missions carried out under modern scientific principles, and the first major international scientific expedition.

3.4K
19 Oct 2022

Topic Review

Climate Change Adaptation in Greenland

Climate change adaptation is a pressing issue in Greenland. The term climate change describes long-term changes to the climate system. Since the 1950s a stark rise in global temperatures has been observed. As climate change, whether natural or anthropogenic, impacts the livelihoods of people across the globe, responses i.e. ways to prepare and adjust under changing vulnerabilities become important. Such responses are commonly discussed under the term adaptation, "the process of adjustment to actual or expected climate and its effects", as defined by the IPCC. Geographically Greenland is situated between the Arctic and the Atlantic Ocean, with one third of the island being north of the Arctic Circle. Since the middle of the 20th century, the Arctic has been warming at about twice the global rate. Rising temperatures put increasing pressure on certain plant and tree species and contribute to Greenland's melting ice sheet. This affects and changes the livelihood of the Greenlandic population, particularly the Inuit people, which make up to 80 percent of the total population. Besides the decline of fish stocks, the country's landscape is changing: the melting ice reveals minerals, oil and gas. This has attracted interest from local and foreign investors for potential resource extraction. As new industries are accompanied by new job opportunities and potential wealth, lifestyles are changing. Greenland is in transition, in terms of biophysical as well as cultural and social conditions.

3.4K
20 Nov 2022

Topic Review

Intermarium (Polish: Międzymorze, Polish pronunciation: [mʲɛnd͡zɨˈmɔʐɛ]) was a geopolitical project conceived by politicians in successor states of the former Polish–Lithuanian Commonwealth in several iterations, some of which anticipated the inclusion as well of other, neighboring states. The proposed multinational polity would have extended across territories lying between the Baltic, Black and Adriatic Seas, hence the name meaning "Between-Seas". Prospectively a federation of Central and Eastern European countries, the post-World War I Intermarium plan pursued by Polish leader and former political prisoner of the Russian Empire, Józef Piłsudski (1867–1935), sought to recruit to the proposed federation the Baltic states (Lithuania, Latvia, Estonia), Finland , Belarus, Ukraine, Hungary, Romania, Yugoslavia and Czechoslovakia. The Polish name Międzymorze (from między, "between"; and morze, "sea"), meaning "Between-Seas", was rendered into Latin as "Intermarium." The proposed federation was meant to emulate the Polish–Lithuanian Commonwealth, stretching from the Baltic Sea to the Black Sea, that, from the end of the 16th century to the end of the 18th, had united the Kingdom of Poland and the Grand Duchy of Lithuania. Intermarium complemented Piłsudski's other geopolitical vision, Prometheism, whose goal was the dismemberment of the Russian Empire and that Empire's divestment of its territorial acquisitions. Intermarium was, however, perceived by some Lithuanians as a threat to their newly established independence, and by some Ukrainians as a threat to their aspirations for independence, and while France backed the proposal, it was opposed by Russia and by most other Western powers. Within two decades of the failure of Piłsudski's grand scheme, all the countries that he had viewed as candidates for membership in the Intermarium federation had fallen to the Soviet Union or Nazi Germany, except for Finland (which suffered some territorial losses in the 1939–40 Winter War with the Soviet Union).

3.3K
19 Oct 2022

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