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78-745: A map is a symbolic visual representation of an area. Map or MAP may also refer to: Map A map is a symbolic depiction of interrelationships, commonly spatial, between things within a space . A map may be annotated with text and graphics. Like any graphic, a map may be fixed to paper or other durable media, or may be displayed on a transitory medium such as a computer screen. Some maps change interactively. Although maps are commonly used to depict geographic elements , they may represent any space, real or fictional. The subject being mapped may be two-dimensional such as Earth's surface, three-dimensional such as Earth's interior, or from an abstract space of any dimension. Maps of geographic territory have

156-516: A map legend on the margin of the map, or on a separately published characteristic sheet. Some cartographers prefer to make the map cover practically the entire screen or sheet of paper, leaving no room "outside" the map for information about the map as a whole. These cartographers typically place such information in an otherwise "blank" region "inside" the map— cartouche , map legend, title, compass rose , bar scale , etc. In particular, some maps contain smaller maps inset into otherwise blank areas of

234-454: A ratio , such as 1:10,000, which means that 1 unit of measurement on the map corresponds to 10,000 of that same unit on the ground. The scale statement can be accurate when the region mapped is small enough for the curvature of the Earth to be neglected, such as a city map . Mapping larger regions, where the curvature cannot be ignored, requires projections to map from the curved surface of

312-470: A broad understanding of the location and features of an area. The reader may gain an understanding of the type of landscape, the location of urban places, and the location of major transportation routes all at once. Polish general Stanisław Maczek had once been shown an impressive outdoor map of land and water in the Netherlands demonstrating the working of the waterways (which had been an obstacle to

390-410: A course of constant bearing is always plotted as a straight line. A normal cylindrical projection is any projection in which meridians are mapped to equally spaced vertical lines and circles of latitude (parallels) are mapped to horizontal lines. The mapping of meridians to vertical lines can be visualized by imagining a cylinder whose axis coincides with the Earth's axis of rotation. This cylinder

468-416: A cylindrical projection (for example) is one which: (If you rotate the globe before projecting then the parallels and meridians will not necessarily still be straight lines. Rotations are normally ignored for the purpose of classification.) Where the light source emanates along the line described in this last constraint is what yields the differences between the various "natural" cylindrical projections. But

546-416: A parallel of origin (usually written φ 0 ) are often used to define the origin of the map projection. A globe is the only way to represent the Earth with constant scale throughout the entire map in all directions. A map cannot achieve that property for any area, no matter how small. It can, however, achieve constant scale along specific lines. Some possible properties are: Projection construction

624-399: A particular purpose for an intended audience. Designing a map involves bringing together a number of elements and making a large number of decisions. The elements of design fall into several broad topics, each of which has its own theory, its own research agenda, and its own best practices. That said, there are synergistic effects between these elements, meaning that the overall design process

702-399: A plane without distortion. The same applies to other reference surfaces used as models for the Earth, such as oblate spheroids , ellipsoids , and geoids . Since any map projection is a representation of one of those surfaces on a plane, all map projections distort. The classical way of showing the distortion inherent in a projection is to use Tissot's indicatrix . For a given point, using

780-406: A proxy for the combination of angular deformation and areal inflation; such methods arbitrarily choose what paths to measure and how to weight them in order to yield a single result. Many have been described. The creation of a map projection involves two steps: Some of the simplest map projections are literal projections, as obtained by placing a light source at some definite point relative to

858-477: A sphere or ellipsoid. Therefore, more generally, a map projection is any method of flattening a continuous curved surface onto a plane. The most well-known map projection is the Mercator projection . This map projection has the property of being conformal . However, it has been criticized throughout the 20th century for enlarging regions further from the equator. To contrast, equal-area projections such as

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936-417: A very long tradition and have existed from ancient times. The word "map" comes from the medieval Latin : Mappa mundi , wherein mappa meant 'napkin' or 'cloth' and mundi 'of the world'. Thus, "map" became a shortened term referring to a flat representation of Earth's surface. Maps have been one of the most important human inventions for millennia, allowing humans to explain and navigate their way through

1014-709: Is according to properties of the model they preserve. Some of the more common categories are: Because the sphere is not a developable surface , it is impossible to construct a map projection that is both equal-area and conformal. The three developable surfaces (plane, cylinder, cone) provide useful models for understanding, describing, and developing map projections. However, these models are limited in two fundamental ways. For one thing, most world projections in use do not fall into any of those categories. For another thing, even most projections that do fall into those categories are not naturally attainable through physical projection. As L. P. Lee notes, No reference has been made in

1092-399: Is also affected by how the shape of the Earth or planetary body is approximated. In the following section on projection categories, the earth is taken as a sphere in order to simplify the discussion. However, the Earth's actual shape is closer to an oblate ellipsoid . Whether spherical or ellipsoidal, the principles discussed hold without loss of generality. Selecting a model for a shape of

1170-510: Is called a cartographer . Road maps are perhaps the most widely used maps today. They are a subset of navigational maps, which also include aeronautical and nautical charts , railroad network maps, and hiking and bicycling maps. In terms of quantity, the largest number of drawn map sheets is probably made up by local surveys, carried out by municipalities , utilities, tax assessors, emergency services providers, and other local agencies. Many national surveying projects have been carried out by

1248-462: Is derived from Latin oriens , meaning east. In the Middle Ages many maps, including the T and O maps , were drawn with east at the top (meaning that the direction "up" on the map corresponds to East on the compass). The most common cartographic convention nowadays is that north is at the top of a map. Maps not oriented with north at the top: Many maps are drawn to a scale expressed as

1326-445: Is given by φ): In the first case (Mercator), the east-west scale always equals the north-south scale. In the second case (central cylindrical), the north-south scale exceeds the east-west scale everywhere away from the equator. Each remaining case has a pair of secant lines —a pair of identical latitudes of opposite sign (or else the equator) at which the east-west scale matches the north-south-scale. Normal cylindrical projections map

1404-588: Is not just working on each element one at a time, but an iterative feedback process of adjusting each to achieve the desired gestalt . Maps of the world or large areas are often either 'political' or 'physical'. The most important purpose of the political map is to show territorial borders ; the purpose of the physical map is to show features of geography such as mountains, soil type, or land use including infrastructures such as roads, railroads, and buildings. Topographic maps show elevations and relief with contour lines or shading. Geological maps show not only

1482-401: Is through grayscale or color gradations whose shade represents the magnitude of the angular deformation or areal inflation. Sometimes both are shown simultaneously by blending two colors to create a bivariate map . To measure distortion globally across areas instead of at just a single point necessarily involves choosing priorities to reach a compromise. Some schemes use distance distortion as

1560-467: Is used by agencies around the world, as diverse as wildlife conservationists and militaries. Even when GIS is not involved, most cartographers now use a variety of computer graphics programs to generate new maps. Interactive, computerized maps are commercially available, allowing users to zoom in or zoom out (respectively meaning to increase or decrease the scale), sometimes by replacing one map with another of different scale, centered where possible on

1638-456: Is wrapped around the Earth, projected onto, and then unrolled. By the geometry of their construction, cylindrical projections stretch distances east-west. The amount of stretch is the same at any chosen latitude on all cylindrical projections, and is given by the secant of the latitude as a multiple of the equator's scale. The various cylindrical projections are distinguished from each other solely by their north-south stretching (where latitude

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1716-487: The Collignon projection in polar areas. The term "conic projection" is used to refer to any projection in which meridians are mapped to equally spaced lines radiating out from the apex and circles of latitude (parallels) are mapped to circular arcs centered on the apex. When making a conic map, the map maker arbitrarily picks two standard parallels. Those standard parallels may be visualized as secant lines where

1794-722: The Sinusoidal projection and the Gall–Peters projection show the correct sizes of countries relative to each other, but distort angles. The National Geographic Society and most atlases favor map projections that compromise between area and angular distortion, such as the Robinson projection and the Winkel tripel projection . Many properties can be measured on the Earth's surface independently of its geography: Map projections can be constructed to preserve some of these properties at

1872-425: The geoid to a two-dimensional picture. Projection always distorts the surface. There are many ways to apportion the distortion, and so there are many map projections. Which projection to use depends on the purpose of the map. The various features shown on a map are represented by conventional signs or symbols. For example, colors can be used to indicate a classification of roads. Those signs are usually explained in

1950-715: The British Columbia Pavilion at the Pacific National Exhibition (PNE) in Vancouver from 1954 to 1997 it was viewed by millions of visitors. The Guinness Book of Records cites the Challenger Map as the largest of its kind in the world. The map in its entirety occupies 6,080 square feet (1,850 square metres) of space. It was disassembled in 1997; there is a project to restore it in a new location. The Relief map of Guatemala

2028-454: The Earth involves choosing between the advantages and disadvantages of a sphere versus an ellipsoid. Spherical models are useful for small-scale maps such as world atlases and globes, since the error at that scale is not usually noticeable or important enough to justify using the more complicated ellipsoid. The ellipsoidal model is commonly used to construct topographic maps and for other large- and medium-scale maps that need to accurately depict

2106-453: The Earth to the plane. The impossibility of flattening the sphere to the plane without distortion means that the map cannot have a constant scale. Rather, on most projections, the best that can be attained is an accurate scale along one or two paths on the projection. Because scale differs everywhere, it can only be measured meaningfully as point scale per location. Most maps strive to keep point scale variation within narrow bounds. Although

2184-466: The Polish forces progress in 1944). This had inspired Maczek and his companions to create Great Polish Map of Scotland as a 70-ton permanent three-dimensional reminder of Scotland's hospitality to his compatriots. In 1974, the coastline and relief of Scotland were laid out by Kazimierz Trafas, a Polish student geographer-planner, based on existing Bartholomew Half-Inch map sheets. Engineering infrastructure

2262-494: The above definitions to cylinders, cones or planes. The projections are termed cylindric or conic because they can be regarded as developed on a cylinder or a cone, as the case may be, but it is as well to dispense with picturing cylinders and cones, since they have given rise to much misunderstanding. Particularly is this so with regard to the conic projections with two standard parallels: they may be regarded as developed on cones, but they are cones which bear no simple relationship to

2340-494: The central meridian. Therefore, meridians are equally spaced along a given parallel. On a pseudocylindrical map, any point further from the equator than some other point has a higher latitude than the other point, preserving north-south relationships. This trait is useful when illustrating phenomena that depend on latitude, such as climate. Examples of pseudocylindrical projections include: The HEALPix projection combines an equal-area cylindrical projection in equatorial regions with

2418-407: The cone intersects the globe—or, if the map maker chooses the same parallel twice, as the tangent line where the cone is tangent to the globe. The resulting conic map has low distortion in scale, shape, and area near those standard parallels. Distances along the parallels to the north of both standard parallels or to the south of both standard parallels are stretched; distances along parallels between

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2496-520: The connectivity is significant. The London Underground map and similar subway maps around the world are a common example of these maps. General-purpose maps provide many types of information on one map. Most atlas maps, wall maps, and road maps fall into this category. The following are some features that might be shown on general-purpose maps: bodies of water, roads, railway lines, parks, elevations, towns and cities, political boundaries, latitude and longitude, national and provincial parks. These maps give

2574-549: The dates of onset of a given phenomenon (for example, the first frost and appearance or disappearance of the snow cover) or the date of a particular value of a meteorological element in the course of a year (for example, passing of the mean daily air temperature through zero). Isolines of the mean numerical value of wind velocity or isotachs are drawn on wind maps (charts); the wind resultants and directions of prevailing winds are indicated by arrows of different lengths or arrows with different plumes; lines of flow are often drawn. Maps of

2652-445: The differences between the mean temperatures of the warmest and coldest month). Isanomals are drawn on maps of anomalies (for example, deviations of the mean temperature of each place from the mean temperature of the entire latitudinal zone). Isolines of frequency are drawn on maps showing the frequency of a particular phenomenon (for example, the annual number of days with a thunderstorm or snow cover). Isochrones are drawn on maps showing

2730-597: The distortion in projections. Like Tissot's indicatrix, the Goldberg-Gott indicatrix is based on infinitesimals, and depicts flexion and skewness (bending and lopsidedness) distortions. Rather than the original (enlarged) infinitesimal circle as in Tissot's indicatrix, some visual methods project finite shapes that span a part of the map. For example, a small circle of fixed radius (e.g., 15 degrees angular radius ). Sometimes spherical triangles are used. In

2808-405: The distribution of pressure at different standard altitudes—for example, at every kilometer above sea level—or by maps of baric topography on which altitudes (more precisely geopotentials) of the main isobaric surfaces (for example, 900, 800, and 700 millibars) counted off from sea level are plotted. The temperature, humidity, and wind on aero climatic maps may apply either to standard altitudes or to

2886-435: The earth's surface and in the upper layers of the atmosphere. Climatic maps show climatic features across a large region and permit values of climatic features to be compared in different parts of the region. When generating the map, spatial interpolation can be used to synthesize values where there are no measurements, under the assumption that conditions change smoothly. Climatic maps generally apply to individual months and

2964-476: The earth's surface into climatic zones and regions according to some classification of climates, are a special kind of climatic map. Climatic maps are often incorporated into climatic atlases of varying geographic ranges (globe, hemispheres, continents, countries, oceans) or included in comprehensive atlases. Besides general climatic maps, applied climatic maps and atlases have great practical value. Aero climatic maps, aero climatic atlases, and agro climatic maps are

3042-428: The edges of the map. Further inaccuracies may be deliberate. For example, cartographers may simply omit military installations or remove features solely to enhance the clarity of the map. For example, a road map may not show railroads, smaller waterways, or other prominent non-road objects, and even if it does, it may show them less clearly (e.g. dashed or dotted lines/outlines) than the main roads. Known as decluttering,

3120-445: The equator and not a meridian. Pseudocylindrical projections represent the central meridian as a straight line segment. Other meridians are longer than the central meridian and bow outward, away from the central meridian. Pseudocylindrical projections map parallels as straight lines. Along parallels, each point from the surface is mapped at a distance from the central meridian that is proportional to its difference in longitude from

3198-458: The expense of others. Because the Earth's curved surface is not isometric to a plane, preservation of shapes inevitably requires a variable scale and, consequently, non-proportional presentation of areas. Similarly, an area-preserving projection can not be conformal , resulting in shapes and bearings distorted in most places of the map. Each projection preserves, compromises, or approximates basic metric properties in different ways. The purpose of

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3276-410: The first half of the 20th century, projecting a human head onto different projections was common to show how distortion varies across one projection as compared to another. In dynamic media, shapes of familiar coastlines and boundaries can be dragged across an interactive map to show how the projection distorts sizes and shapes according to position on the map. Another way to visualize local distortion

3354-433: The geoid are used to project maps from. Other regular solids are sometimes used as generalizations for smaller bodies' geoidal equivalent. For example, Io is better modeled by triaxial ellipsoid or prolated spheroid with small eccentricities. Haumea 's shape is a Jacobi ellipsoid , with its major axis twice as long as its minor and with its middle axis one and half times as long as its minor. See map projection of

3432-400: The globe and projecting its features onto a specified surface. Although most projections are not defined in this way, picturing the light source-globe model can be helpful in understanding the basic concept of a map projection. A surface that can be unfolded or unrolled into a plane or sheet without stretching, tearing or shrinking is called a developable surface . The cylinder , cone and

3510-429: The globe never preserves or optimizes metric properties, so that possibility is not discussed further here. Tangent and secant lines ( standard lines ) are represented undistorted. If these lines are a parallel of latitude, as in conical projections, it is called a standard parallel . The central meridian is the meridian to which the globe is rotated before projecting. The central meridian (usually written λ 0 ) and

3588-498: The land surface. Auxiliary latitudes are often employed in projecting the ellipsoid. A third model is the geoid , a more complex and accurate representation of Earth's shape coincident with what mean sea level would be if there were no winds, tides, or land. Compared to the best fitting ellipsoid, a geoidal model would change the characterization of important properties such as distance, conformality and equivalence . Therefore, in geoidal projections that preserve such properties,

3666-480: The left) of Europe has been distorted to show population distribution, while the rough shape of the continent is still discernible. Another example of distorted scale is the famous London Underground map . The geographic structure is respected but the tube lines (and the River Thames ) are smoothed to clarify the relationships between stations. Near the center of the map, stations are spaced out more than near

3744-458: The main isobaric surfaces. Isolines are drawn on maps of such climatic features as the long-term mean values (of atmospheric pressure, temperature, humidity, total precipitation, and so forth) to connect points with equal values of the feature in question—for example, isobars for pressure, isotherms for temperature, and isohyets for precipitation. Isoamplitudes are drawn on maps of amplitudes (for example, annual amplitudes of air temperature—that is,

3822-466: The map determines which projection should form the base for the map. Because maps have many different purposes, a diversity of projections have been created to suit those purposes. Another consideration in the configuration of a projection is its compatibility with data sets to be used on the map. Data sets are geographic information; their collection depends on the chosen datum (model) of the Earth. Different datums assign slightly different coordinates to

3900-462: The map: for example: The design and production of maps is a craft that has developed over thousands of years, from clay tablets to Geographic information systems . As a form of Design , particularly closely related to Graphic design , map making incorporates scientific knowledge about how maps are used, integrated with principles of artistic expression, to create an aesthetically attractive product, carries an aura of authority, and functionally serves

3978-427: The mapped graticule would deviate from a mapped ellipsoid's graticule. Normally the geoid is not used as an Earth model for projections, however, because Earth's shape is very regular, with the undulation of the geoid amounting to less than 100 m from the ellipsoidal model out of the 6.3 million m Earth radius . For irregular planetary bodies such as asteroids , however, sometimes models analogous to

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4056-521: The military, such as the British Ordnance Survey : a civilian government agency, internationally renowned for its comprehensively detailed work. The location information showed by maps may include contour lines , indicating constant values of elevation , temperature, rainfall, etc. The orientation of a map is the relationship between the directions on the map and the corresponding compass directions in reality. The word " orient "

4134-579: The most numerous. Maps exist of the Solar System , and other cosmological features such as star maps . In addition maps of other bodies such as the Moon and other planets are technically not geo graphical maps. Floor maps are also spatial but not necessarily geospatial. Diagrams such as schematic diagrams and Gantt charts and tree maps display logical relationships between items, rather than geographic relationships. Topological in nature, only

4212-429: The physical surface, but characteristics of the underlying rock, fault lines, and subsurface structures. From the last quarter of the 20th century, the indispensable tool of the cartographer has been the computer. Much of cartography, especially at the data-gathering survey level, has been subsumed by geographic information systems (GIS). The functionality of maps has been greatly advanced by technology simplifying

4290-403: The plane are all developable surfaces. The sphere and ellipsoid do not have developable surfaces, so any projection of them onto a plane will have to distort the image. (To compare, one cannot flatten an orange peel without tearing and warping it.) One way of describing a projection is first to project from the Earth's surface to a developable surface such as a cylinder or cone, and then to unroll

4368-431: The plane is a projection. Few projections in practical use are perspective. Most of this article assumes that the surface to be mapped is that of a sphere. The Earth and other large celestial bodies are generally better modeled as oblate spheroids , whereas small objects such as asteroids often have irregular shapes. The surfaces of planetary bodies can be mapped even if they are too irregular to be modeled well with

4446-413: The practice makes the subject matter that the user is interested in easier to read, usually without sacrificing overall accuracy. Software-based maps often allow the user to toggle decluttering between ON, OFF, and AUTO as needed. In AUTO the degree of decluttering is adjusted as the user changes the scale being displayed. Geographic maps use a projection to translate the three-dimensional real surface of

4524-468: The projection surface into a flat map. The most common projection surfaces are cylindrical (e.g., Mercator ), conic (e.g., Albers ), and planar (e.g., stereographic ). Many mathematical projections, however, do not neatly fit into any of these three projection methods. Hence other peer categories have been described in the literature, such as pseudoconic, pseudocylindrical, pseudoazimuthal, retroazimuthal, and polyconic . Another way to classify projections

4602-438: The same location, so in large scale maps, such as those from national mapping systems, it is important to match the datum to the projection. The slight differences in coordinate assignation between different datums is not a concern for world maps or those of large regions, where such differences are reduced to imperceptibility. Carl Friedrich Gauss 's Theorema Egregium proved that a sphere's surface cannot be represented on

4680-571: The same point. In-car global navigation satellite systems are computerized maps with route planning and advice facilities that monitor the user's position with the help of satellites. From the computer scientist's point of view, zooming in entails one or more of: For example: The maps that reflect the territorial distribution of climatic conditions based on the results of long-term observations are called climatic maps . These maps can be compiled both for individual climatic features (temperature, precipitation, humidity) and for combinations of them at

4758-440: The scale factor h along the meridian, the scale factor k along the parallel, and the angle θ ′ between them, Nicolas Tissot described how to construct an ellipse that illustrates the amount and orientation of the components of distortion. By spacing the ellipses regularly along the meridians and parallels, the network of indicatrices shows how distortion varies across the map. Many other ways have been described of showing

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4836-454: The scale statement is nominal it is usually accurate enough for most purposes unless the map covers a large fraction of the Earth. At the scope of a world map, scale as a single number is practically meaningless throughout most of the map. Instead, it usually refers to the scale along the equator. Some maps, called cartograms , have the scale deliberately distorted to reflect information other than land area or distance. For example, this map (at

4914-427: The sphere. In reality, cylinders and cones provide us with convenient descriptive terms, but little else. Lee's objection refers to the way the terms cylindrical , conic , and planar (azimuthal) have been abstracted in the field of map projections. If maps were projected as in light shining through a globe onto a developable surface, then the spacing of parallels would follow a very limited set of possibilities. Such

4992-423: The standard parallels are compressed. When a single standard parallel is used, distances along all other parallels are stretched. Conic projections that are commonly used are: Azimuthal projections have the property that directions from a central point are preserved and therefore great circles through the central point are represented by straight lines on the map. These projections also have radial symmetry in

5070-402: The superimposition of spatially located variables onto existing geographic maps. Having local information such as rainfall level, distribution of wildlife, or demographic data integrated within the map allows more efficient analysis and better decision making. In the pre-electronic age such superimposition of data led Dr. John Snow to identify the location of an outbreak of cholera . Today, it

5148-574: The surface in some way. Depending on the purpose of the map, some distortions are acceptable and others are not; therefore, different map projections exist in order to preserve some properties of the sphere-like body at the expense of other properties. The study of map projections is primarily about the characterization of their distortions. There is no limit to the number of possible map projections. More generally, projections are considered in several fields of pure mathematics, including differential geometry , projective geometry , and manifolds . However,

5226-403: The surface into a plane. While the first step inevitably distorts some properties of the globe, the developable surface can then be unfolded without further distortion. Once a choice is made between projecting onto a cylinder, cone, or plane, the aspect of the shape must be specified. The aspect describes how the developable surface is placed relative to the globe: it may be normal (such that

5304-432: The surface's axis of symmetry coincides with the Earth's axis), transverse (at right angles to the Earth's axis) or oblique (any angle in between). The developable surface may also be either tangent or secant to the sphere or ellipsoid. Tangent means the surface touches but does not slice through the globe; secant means the surface does slice through the globe. Moving the developable surface away from contact with

5382-407: The term cylindrical as used in the field of map projections relaxes the last constraint entirely. Instead the parallels can be placed according to any algorithm the designer has decided suits the needs of the map. The famous Mercator projection is one in which the placement of parallels does not arise by projection; instead parallels are placed how they need to be in order to satisfy the property that

5460-423: The term "map projection" refers specifically to a cartographic projection. Despite the name's literal meaning, projection is not limited to perspective projections, such as those resulting from casting a shadow on a screen, or the rectilinear image produced by a pinhole camera on a flat film plate. Rather, any mathematical function that transforms coordinates from the curved surface distinctly and smoothly to

5538-422: The triaxial ellipsoid for further information. One way to classify map projections is based on the type of surface onto which the globe is projected. In this scheme, the projection process is described as placing a hypothetical projection surface the size of the desired study area in contact with part of the Earth, transferring features of the Earth's surface onto the projection surface, then unraveling and scaling

5616-411: The whole Earth as a finite rectangle, except in the first two cases, where the rectangle stretches infinitely tall while retaining constant width. A transverse cylindrical projection is a cylindrical projection that in the tangent case uses a great circle along a meridian as contact line for the cylinder. See: transverse Mercator . An oblique cylindrical projection aligns with a great circle, but not

5694-491: The world. The earliest surviving maps include cave paintings and etchings on tusk and stone. Later came extensive maps produced in ancient Babylon , Greece and Rome , China , and India . In their simplest forms, maps are two-dimensional constructs. Since the Classical Greek period , however, maps also have been projected onto globes . The Mercator Projection , developed by Flemish geographer Gerardus Mercator ,

5772-424: The year as a whole, sometimes to the four seasons, to the growing period, and so forth. On maps compiled from the observations of ground meteorological stations, atmospheric pressure is converted to sea level. Air temperature maps are compiled both from the actual values observed on the surface of the Earth and from values converted to sea level. The pressure field in the free atmosphere is represented either by maps of

5850-410: The zonal and meridional components of wind are frequently compiled for the free atmosphere. Atmospheric pressure and wind are usually combined on climatic maps. Wind roses, curves showing the distribution of other meteorological elements, diagrams of the annual course of elements at individual stations, and the like are also plotted on climatic maps. Maps of climatic regionalization, that is, division of

5928-409: Was made by Francisco Vela in 1905 and still exists. This map (horizontal scale 1:10,000; vertical scale 1:2,000) measures 1,800 m , and was created to educate children in the scape of their country. Some countries required that all published maps represent their national claims regarding border disputes . For example: Map projection All projections of a sphere on a plane necessarily distort

6006-599: Was put in place to surround it with a sea of water and at the General's request some of the main rivers were even arranged to flow from headwaters pumped into the mountains. The map was finished in 1979, but had to be restored between 2013 and 2017. The Challenger Relief Map of British Columbia is a hand-built topographic map of the province, 80 feet by 76 feet. Built by George Challenger and his family from 1947 to 1954, it features all of B.C.'s mountains, lakes, rivers and valleys in exact-scaled topographical detail. Residing in

6084-420: Was widely used as the standard for two-dimensional world maps until the late 20th century, when more accurate projections were more widely used. Mercator also was the first to use and popularize the concept of the atlas : a collection of maps. Cartography or map-making is the study and practice of crafting representations of the Earth upon a flat surface (see History of cartography ), and one who makes maps

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