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NAD83
The North American Datum (NAD) is the horizontal datum now used to define the geodetic network in North America. A datum is a formal description of the shape of the Earth along with an "anchor" point for the coordinate system. In surveying, cartography, and land-use planning, two North American Datums are in use for making lateral or "horizontal" measurements: the North American Datum of 1927 (NAD 27) and the North American Datum of 1983 (NAD 83). Both are geodetic reference systems based on slightly different assumptions and measurements. Vertical measurements, based on distances above or below Mean High Water (MHW), are calculated using the North American Vertical Datum of 1988 (NAVD 88). NAD 83, along with NAVD 88, is set to be replaced with a new GPS- and gravimetric geoid model-based geometric reference frame and geopotential datum in 2022. First North American Datum of 1901 In 1901 the United States Coast and Geodetic Survey adopted a national horizontal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geodetic Datum
A geodetic datum or geodetic system (also: geodetic reference datum, geodetic reference system, or geodetic reference frame) is a global datum reference or reference frame for precisely representing the position of locations on Earth or other planetary bodies by means of '' geodetic 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 location across the Earth's surface, in latitude and longitude or another coordinate system; a ''vertical datum'' is used to measure the elevation or depth relative to a standard origin, such as mean sea level (MSL). Since the rise of the global positioning system (GPS), the ellipsoid and datum WGS 84 it uses has supplanted most others in many applications. The WGS 84 is intended for global use, unlike most earlier datums. Be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geodetic Reference System
A geodetic datum or geodetic system (also: geodetic reference datum, geodetic reference system, or geodetic reference frame) is a global datum reference or reference frame for precisely representing the position of locations on Earth or other planetary bodies by means of ''geodetic 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 location across the Earth's surface, in latitude and longitude or another coordinate system; a ''vertical datum'' is used to measure the elevation or depth relative to a standard origin, such as mean sea level (MSL). Since the rise of the global positioning system (GPS), the ellipsoid and datum WGS 84 it uses has supplanted most others in many applications. The WGS 84 is intended for global use, unlike most earlier datums. Befo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meades Ranch Triangulation Station
The Meades Ranch Triangulation Station is a survey marker in Osborne County in the state of Kansas in the Midwestern United States. The marker was initially placed in 1891. From 1901, it was the reference location for establishing a system of horizontal measurement in the United States, known as geodetic datum. In 1913, the datum was adopted across all of North America, and the system revised and formalized as the North American Datum of 1927 (NAD27). A similar reference for vertical measurement was established in 1929 as the National Geodetic Vertical Datum of 1929. The NAD27 was later supplanted by the North American Datum of 1983 (NAD83), which was formally adopted by the United States in 1989 and Canada in 1990; the new system moved the reference point to a point in the earth's core, and the Meades Ranch marker lost its special significance to the geodetic datum system. In 1973, the site was listed in the National Register of Historic Places as Geodetic Center of the U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrangle (geography)
A "quadrangle" is a topographic map produced by the United States Geological Survey (USGS) covering the United States. The maps are usually named after local physiographic features. The shorthand "quad" is also used, especially with the name of the map; for example, "the Ranger Creek, Texas quad". From approximately 1947-1992, the USGS produced the 7.5 minute series, with each map covering an area one-quarter of the older 15-minute quad series, which it replaced. A 7.5 minute quadrangle map covers an area of . Both map series were produced via photogrammetry, photogrammetric analysis of aerial photography using stereoplotters supplemented by field surveys. These maps employ the 1927 North American Datum (NAD27); conversion or a change in settings is necessary when using a GPS which by default employ the WGS84 geodetic datum. Beginning in 2009, the USGS made available digital versions of 7.5 minute quadrangle maps based on geographic information system, GIS data that use the North A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cartography
Cartography (; from grc, χάρτης , "papyrus, sheet of paper, map"; and , "write") is the study and practice of making and using maps. Combining science, aesthetics and technique, cartography builds on the premise that reality (or an imagined reality) can be modeled in ways that communicate spatial information effectively. The fundamental objectives of traditional cartography are to: * Set the map's agenda and select traits of the object to be mapped. This is the concern of map editing. Traits may be physical, such as roads or land masses, or may be abstract, such as toponyms or political boundaries. * Represent the terrain of the mapped object on flat media. This is the concern of map projections. * Eliminate characteristics of the mapped object that are not relevant to the map's purpose. This is the concern of generalization. * Reduce the complexity of the characteristics that will be mapped. This is also the concern of generalization. * Orchestrate the elements of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waldo, Kansas
Waldo is a city in Waldo Township, Russell County, Kansas, United States. As of the 2020 census, the population of the city was 30. History The Union Town Company established the town of Waldo on October 1, 1888, having acquired 280 acres of land on a line of the Union Pacific Railroad. The community grew over the following decades, reaching a population of approximately 300 by 1915. A small business community, including a bank, stores, and three grain elevators, developed during the 1900s. The town served as an agricultural shipping and receiving point for the surrounding area. Waldo incorporated as a city in May 1911. Since the 1930s, the population of the community has gradually declined. Waldo High School closed in 1964, followed by Waldo Grade School in 1979. In 1993, Union Pacific abandoned its rail line through Waldo, ending rail service to the community. Geography Waldo is located at (39.120162, -98.797863) at an elevation of 1,713 feet (522 m). The community is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NOAA
The National Oceanic and Atmospheric Administration (abbreviated as NOAA ) is an United States scientific and regulatory agency within the United States Department of Commerce that forecasts weather, monitors oceanic and atmospheric conditions, charts the seas, conducts deep sea exploration, and manages fishing and protection of marine mammals and endangered species in the U.S. exclusive economic zone. Purpose and function NOAA's specific roles include: * ''Supplying Environmental Information Products''. NOAA supplies to its customers and partners information pertaining to the state of the oceans and the atmosphere, such as weather warnings and forecasts via the National Weather Service. NOAA's information services extend as well to climate, ecosystems, and commerce. * ''Providing Environmental Stewardship Services''. NOAA is a steward of U.S. coastal and marine environments. In coordination with federal, state, local, tribal and international authorities, NOAA manages the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geocentric Model
In astronomy, the geocentric model (also known as geocentrism, often exemplified specifically by the Ptolemaic system) is a superseded description of the Universe with Earth at the center. Under most geocentric models, the Sun, Moon, stars, and planets all orbit Earth. The geocentric model was the predominant description of the cosmos in many European ancient civilizations, such as those of Aristotle in Classical Greece and Ptolemy in Roman Egypt. Two observations supported the idea that Earth was the center of the Universe: * First, from anywhere on Earth, the Sun appears to revolve around Earth once per day. While the Moon and the planets have their own motions, they also appear to revolve around Earth about once per day. The stars appeared to be fixed on a celestial sphere rotating once each day about an axis through the geographic poles of Earth. * Second, Earth seems to be unmoving from the perspective of an earthbound observer; it feels solid, stable, and stationary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Datum Shift Between NAD27 And NAD83
In the pursuit of knowledge, data (; ) is a collection of discrete values that convey information, describing quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted. A datum is an individual value in a collection of data. Data is usually organized into structures such as tables that provide additional context and meaning, and which may themselves be used as data in larger structures. Data may be used as variables in a computational process. Data may represent abstract ideas or concrete measurements. Data is commonly used in scientific research, economics, and in virtually every other form of human organizational activity. Examples of data sets include price indices (such as consumer price index), unemployment rates, literacy rates, and census data. In this context, data represents the raw facts and figures which can be used in such a manner in order to capture the useful information out of it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World Geodetic System
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. Definition The coordinate origin of WGS 84 is meant to be located at the Earth's center of mass; the uncertainty is believed to be less than . The WGS 84 meridian of zero longitude is the IERS Reference Meridian, European Organisation for the Safety of Air Navigation and IfEN: WGS 84 Implementation Manual, p. 13. 1998 5.3 arc seconds or east of the Greenwich meridian at the latitude of the Royal Observatory. (This is related to the fact that the local gravity field at Greenwich doesn't point exactly through the Earth's center of mass, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GRS 80
The Geodetic Reference System 1980 (GRS 80) is a geodetic reference system consisting of a global reference ellipsoid and a normal gravity model. 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 masses. The geoid, unlike the ellipsoid, is irregular and too complicated to serve as the computational surface on which to solve geometrical problems like point positioning. The geometrical separation between it and the reference ellipsoid is called the geoidal undulation, or more usually the geoid-ellipsoid separation, ''N'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Civilian
Civilians under international humanitarian law are "persons who are not members of the armed forces" and they are not " combatants if they carry arms openly and respect the laws and customs of war". It is slightly different from a non-combatant, because some non-combatants are not civilians (for example, military chaplains who are attached to the belligerent party or military personnel who are serving with a neutral country). Civilians in the territories of a party to an armed conflict are entitled to certain privileges under the customary laws of war and international treaties such as the Fourth Geneva Convention. The privileges that they enjoy under international law depends on whether the conflict is an internal one (a civil war) or an international one. In some nations, uniformed members of civilian police or fire departments colloquially refer to members of the public as civilians. Etymology The word "civilian" goes back to the late 14th century and is from Old French ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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