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British National Grid Reference System
The Ordnance Survey National Grid reference system (OSGB), also known as British National Grid (BNG), is a system of geographic grid references, distinct from latitude and longitude, whereby any location in Great Britain can be described in terms of its distance from the origin (0, 0), which lies to the west of the Isles of Scilly. The Ordnance Survey (OS) devised the national grid reference system, and it is heavily used in its survey data, and in maps based on those surveys, whether published by the Ordnance Survey or by commercial map producers. Grid references are also commonly quoted in other publications and data sources, such as guide books and government planning documents. A number of different systems exist that can provide grid references for locations within the British Isles: this article describes the system created solely for Great Britain and its outlying islands (including the Isle of Man). The Irish grid reference system is a similar system created by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grid Reference
A projected coordinate systemalso called a projected coordinate reference system, planar coordinate system, or grid reference systemis a type of spatial reference system that represents locations on Earth using Cartesian coordinate system, Cartesian coordinates (''x'', ''y'') on a planar surface created by a particular map projection. Each projected coordinate system, such as "Universal Transverse Mercator WGS 84 Zone 26N," is defined by a choice of map projection (with specific parameters), a choice of geodetic datum to bind the coordinate system to real locations on the earth, an origin point, and a choice of unit of measure. Hundreds of projected coordinate systems have been specified for various purposes in various regions. When the first standardized coordinate systems were created during the 20th century, such as the Universal Transverse Mercator, State Plane Coordinate System, and British National Grid, they were commonly called ''grid systems''; the term is still common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beast Cliff
Beast Cliff is a steep sea cliff situated about halfway between Whitby and Scarborough, North Yorkshire, Scarborough on the coast of North Yorkshire in northeastern England. Beast Cliff is at the southern end of a coastal region designated as a Special Area of Conservation and Site of Special Scientific Interest. Bordering the eastern edge of the North York Moors national park, the Cleveland Way runs at the head of the cliffs. In terms of its position on the Ordnance Survey National Grid system of geographical mapping, Beast Cliff is mostly in the one-kilometre grid square but at its northern end it extends into . That point is the only area of land in the entire 100-kilometre national grid square of , adjoining , and . Description Beast Cliff is formed from rocks of Jurassic sandstone and shale and is highly vegetated with a wide variety of flora. Scrub and woodland grow on a moderately sloping intermediate plateau part way down the main cliff. This plateau separates lower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WGS84
The World Geodetic System (WGS) is a standard used in cartography, geodesy, and satellite navigation including GPS. The current version, WGS 84, defines an Earth-centered, Earth-fixed coordinate system and a geodetic datum, and also describes the associated Earth Gravitational Model (EGM) and World Magnetic Model (WMM). The standard is published and maintained by the United States National Geospatial-Intelligence Agency. History Efforts to supplement the various national surveying systems began in the 19th century with F.R. Helmert's book (''Mathematical and Physical Theories of Physical Geodesy''). Austria and Germany founded the (Central Bureau of International Geodesy), and a series of global ellipsoids of the Earth were derived (e.g., Helmert 1906, Hayford 1910 and 1924). A unified geodetic system for the whole world became essential in the 1950s for several reasons: * International space science and the beginning of astronautics. * The lack of inter-continental ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GRS80
The Geodetic Reference System 1980 (GRS80) consists of a global reference ellipsoid and a normal gravity model. The GRS80 gravity model has been followed by the newer more accurate Earth Gravitational Models, but the GRS80 reference ellipsoid is still the most accurate in use for coordinate reference systems, e.g. for the international ITRS, the European ETRS89 and (with a 0,1 mm rounding error) for WGS 84 used for the American Global Navigation Satellite System (GPS). Background Geodesy is the scientific discipline that deals with the measurement and representation of the earth, its gravitational field and geodynamic phenomena (polar motion, earth tides, and crustal motion) in three-dimensional, time-varying space. The geoid is essentially the figure of the Earth abstracted from its topographic features. It is an idealized equilibrium surface of sea water, the mean sea level surface in the absence of currents, air pressure variations etc. and continued under the continental m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Biddell Airy
Sir George Biddell Airy (; 27 July 18012 January 1892) was an English mathematician and astronomer, as well as the Lucasian Professor of Mathematics from 1826 to 1828 and the seventh Astronomer Royal from 1835 to 1881. His many achievements include work on planetary orbits, measuring the mean density of the Earth, a method of solution of two-dimensional problems in solid mechanics and, in his role as Astronomer Royal, establishing Greenwich as the location of the prime meridian. Biography Airy was born at Alnwick in Northumberland, one of a long line of Airys who traced their descent back to a family of the same name residing at Kentmere, in Westmorland, in the 14th century. The branch to which he belonged, having suffered in the English Civil War, moved to Lincolnshire and became farmers. Airy was educated first at elementary schools in Hereford, and afterwards at Colchester Royal Grammar School. An introverted child, Airy gained popularity with his schoolmates through his grea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reference Ellipsoid
An Earth ellipsoid or Earth spheroid is a mathematical figure approximating the Earth's form, used as a reference frame for computations in geodesy, astronomy, and the geosciences. Various different ellipsoids have been used as approximations. It is a spheroid (an ellipsoid of revolution) whose minor axis (shorter diameter), which connects the geographical North Pole and South Pole, is approximately aligned with the Earth's axis of rotation. The ellipsoid is defined by the ''equatorial axis'' () and the ''polar axis'' (); their radial difference is slightly more than 21 km, or 0.335% of (which is not quite 6,400 km). Many methods exist for determination of the axes of an Earth ellipsoid, ranging from meridian arcs up to modern satellite geodesy or the analysis and interconnection of continental geodetic networks. Amongst the different set of data used in national surveys are several of special importance: the Bessel ellipsoid of 1841, the international Hayfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Datum Transformation
In geodesy, conversion among different geographic coordinate systems is made necessary by the different geographic coordinate systems in use across the world and over time. Coordinate conversion is composed of a number of different types of conversion: format change of geographic coordinates, conversion of coordinate systems, or transformation to different geodetic datums. Geographic coordinate conversion has applications in cartography, surveying, navigation and geographic information systems. In geodesy, geographic coordinate ''conversion'' is defined as translation among different coordinate formats or map projections all referenced to the same geodetic datum. A geographic coordinate ''transformation'' is a translation among different geodetic datums. Both geographic coordinate conversion and transformation will be considered in this article. This article assumes readers are already familiar with the content in the articles geographic coordinate system and geodetic datum. Chang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassini Grid
The Cassini Grid was a grid coordinate system used on British military maps during the first half of the twentieth century, particularly during World War II. The referencing consists of square grids drawn on a Cassini projection. For a period after the war, the maps were also used by the general public. The system has been superseded by the Ordnance Survey National Grid. History The Cassini Grid system was introduced in 1927 for maps of the United Kingdom for the British military. It is so called from the use of Cassini map projection. It modified and replaced a grid coordinate system first deployed in 1919 known as the ''British System''. The Cassini Grid system is thus more properly called the Modified British System. It may also be referred to as Military Grid, War Office Grid, or Purple Grid (due to the grid colour on some issues of maps). It continued in use until some time after World War II.The Defence of East Sussex ProjectMilitary Maps, accessed anarchived27 Septem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retriangulation Of Great Britain
The Retriangulation of Great Britain was a triangulation (surveying), triangulation project carried out between 1935 and 1962 that sought to improve the accuracy of maps of Great Britain. Data gathered from the retriangulation replaced data gathered during the Principal Triangulation of Great Britain, which had been performed between 1783 and 1851. The work was designed to form a complete new Geodetic control network, survey control network for the whole country, and to unify the Map, mapping of the United Kingdom from local County (United Kingdom), county Map projection, projections into a single national Geodetic datum, datum projection and reference system. Its completion led to the establishment of the OSGB36 datum and Ordnance Survey National Grid in use today. History and overview The retriangulation was begun in 1935 by the Director General of the Ordnance Survey, Major-General Malcolm MacLeod (scientist), Malcolm MacLeod. It was directed by the cartographer and mathe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Map Datum
A geodetic datum or geodetic system (also: geodetic reference datum, geodetic reference system, or geodetic reference frame, or terrestrial reference frame) is a global datum reference or reference frame for unambiguously representing the position of locations on Earth by means of either geodetic coordinates (and related vertical coordinates) or geocentric coordinates. DatumsThe plural is not "data" in this case are crucial to any technology or technique based on spatial location, including geodesy, navigation, surveying, geographic information systems, remote sensing, and cartography. A horizontal datum is used to measure a horizontal position, across the Earth's surface, in latitude and longitude or another related coordinate system. A ''vertical datum'' is used to measure the elevation or depth relative to a standard origin, such as mean sea level (MSL). A three-dimensional datum enables the expression of both horizontal and vertical position components in a unified form. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shetland
Shetland (until 1975 spelled Zetland), also called the Shetland Islands, is an archipelago in Scotland lying between Orkney, the Faroe Islands, and Norway, marking the northernmost region of the United Kingdom. The islands lie about to the northeast of Orkney, from mainland Scotland and west of Norway. They form part of the border between the Atlantic Ocean to the west and the North Sea to the east. The island's area is and the population totalled in . The islands comprise the Shetland (Scottish Parliament constituency), Shetland constituency of the Scottish Parliament. The islands' administrative centre, largest settlement and only burgh is Lerwick, which has been the capital of Shetland since 1708, before which time the capital was Scalloway. Due to its location it is accessible only by ferry or flight with an airport located in Sumburgh as well as a port and emergency airstrip in Lerwick. The archipelago has an oceanic climate, complex geology, rugged coastline, and m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sullom Voe Oil Terminal
The Sullom Voe Terminal is an oil and gas terminal at Sullom Voe in the Shetland Islands of Scotland. It handles production from oilfields in the North Sea Oil, North Sea and East Shetland Basin and stores oil before it is transported by tanker. Construction When Shetland was identified as a location to provide pipeline terminal and support facilities for offshore oil installations in the northern North Sea, corporations involved had expected to each build their own terminal facilities. However, wishing to minimize the negative impacts of the industry, the Shetland Islands Council, with power granted to it by the UK Parliament in the 1974 Zetland County Council Act, was able to contain all pipeline terminal facilities at the Sullom Voe site. Sullom Voe Terminal was built between 1975 and 1981. 6,000 people were employed during construction. They were housed in temporary accommodation, including the former Roll-on/roll-off, car ferry . The first oil was received at 18:40 on 25 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
