The circle gives the impression that worcester is approximately the same distance from boston as new hampshire, and that the state is nearly five times longer, east to west, as it is northtosouth. Map projections and types 1 map projections and types 2 cartography. Apr 25, 2017 map projections without distortions would represent the correct distance, direction, shapes, and areas on a map. Page 79 discuss map scale and the basics of coordinate systems. Map projections explained a beginners guide youtube.
It is perpendicular to the direction of gravity pull. Types of map projections based on developable surface one way of classifying map projections is by the type of the developable surface onto which the reference sphere is projected. The map of massachusetts in unprojected decimal degrees of longitude and latitude note the proportion of the lines and the circle. Ppt map projections and types powerpoint presentation. Shine a light from the center of the earth, trace the image that is projected onto the paper, and then take the paper o. Map projection definition of map projection by the free. The first half of the book focuses on datums, exploring different coordinate systems and datums, including two and threedimensional representations of earth coordinates and vertical datums. The following concepts are addressed in the powerpoint. This is a digital copy of a book that was preserved for. Cylindrical wrap a piece of paper around the earth to form a cylinder that touches the equater all the way around the earth. The map scale may be expressed in three ways and the pictorial representation of these three types is shown in the figure. The shape of the earth and the geodetic datum concept are covered on pages 46. The art and science of making maps, including data compilation, layout, and design. Map projections without distortions would represent the correct distance, direction, shapes, and areas on a map.
Because maps are flat, some of the simplest projections are made onto geometric shapes that can be flattened without stretching their surfaces. Map projection a map projection is a systematic transformation of the latitudes and longitudes of locations on the surface of a sphere or an ellipsoid into locations on a plane. Start studying ap human geography test 1 types of map projections. A stone tablet found in a cave in abauntz in the navarra region of. Spatial thinkingwhy we use maps in geography map projectiondistortions in map projections goodes.
Scale distortions on map projections map projections without distortions would represent the correct distance, direction, shapes, and areas on a map. Map projections are introduced on pages 1012, and pages. It also provides its information in a wellorganized manner. Geodesy, coordinate systems, and map projections objectives introduce the main concepts of geodesy coordinate systems, datums, ellipsoids, and geoids describe map projections and coordinate systems we use in gis two key questions what is the shape of the earth, and where are things on the earth. However, map projections have distortions which depend largely on the size of the area being mapped. So map projections are chosen based on the purposes of the map. The geoid is defined as the surface of the earths gravity field, which is approximately the same as mean sea level. Geological survey usgs now uses several of the more common projections for its published maps. Also concerned with the interpretation of mapped patterns. Which projection is most suitably used for which area. The types of distortion can be controlled to preserve. Improve your knowledge of map projections in this interactive quizworksheet combo.
A scale tells you the ratio of a distance on the map to the actual distance in real life. Pdf map projections download full pdf book download. Jun 06, 2017 the map scale may be expressed in three ways and the pictorial representation of these three types is shown in the figure. Geological survey professional paper 1453, by john p. Map projections displaying the earth on 2 dimensional maps the world from space projection from esri, centered at 72 west and 23 south. Chapter 3 map projections map projection a geometrical transformation of the earths spherical or ellipsoidal surface onto a flat map surface globes provide the most realistic picture of the earth. This site is like a library, use search box in the widget to get ebook that you want. This is a summary of map projections that have articles of their own on wikipedia or that are. Map projections can be created mechanically or mathematically.
Ap human geography test 1 types of map projections. Creating map projections used to be a very hard thing to do. Ap human geography test 1 types of map projections flashcards. Understanding map projections landing page for kartoweb.
The chronology is summarized in tables 2 and 3 and needs only a few additional remarks. Free of distortion at the central meridian at 3646 n. Today, it is usually the job of the cartographer or editor to choose a suitable map projection, taking into account the purpose of the map. Pdf in this paper, we introduce some known map projections from a model of the earth to a flat sheet of paper or map and derive the plotting equations. Only the tm and utm projections are considered in this paper. In this map worksheet, students read about mapping the earths surface and answer questions about globes, maps, cartographers, types of map projections and reading maps. Com s 477577 notes yanbin jia sep 1, 2016 1 foreshortening ratio two types of projection, parallel and perspective, have been introduced. Download our lakes and rivers map of the united states. Click download or read online button to get map projections book now. Feb 21, 2011 conformal projections retain correct angular relations in transfer from globe to map. The post1973 editions of the alaska map e more nearly approximate an equidistant conic map projection. Jan 06, 2017 learn what a map projection is, why they are used and what impact they have on maps gis systems. This is a summary of map projections that have articles of their own on wikipedia or that are otherwise notable.
Types of map projections portland state university. Map projections article about map projections by the free. After an overview of the global positioning system gps, the author introduces the fundamentals of map projections and examines the different types. Jan 22, 2011 the usgs has posted a scanned file of john p. The post1973 editions of the alaska map e more nearly. Although the projection procedure inevitably introduces systematic spatial distortions, particular types of distortion can be minimized to suit the geographic scope and intended use of the map data. Manual by lev bugayevskiy and john snyder, ball state. A tutorial on map projections and geographic coordinate systems. Map projections article about map projections by the. In this map instructional activity, students read about mapping the earths surface and answer questions about globes, maps, cartographers, types of map projections and reading maps. Use this lesson to teach geography classes about types of maps and map projections with great examples and an easytofollow companion worksheet. Many common map projections are classified according to the projection surface used. Projector, free software can render many projections nasa giss.
A cornucopia of map projections, a visualization of distortion on a vast array of map projections in a single image. Map projections massachusetts institute of technology. Description of three different types of map projections. There are many types of map projections, and each one uses a different mathematical formula to. Aug 06, 2019 certain map projections, or ways of displaying the earth in the most accurate ways by scale, are more wellknown and used than other kinds. Since the mass of the earth is not uniform at all points, and the direction of gravity changes, the shape of the geoid is irregular. Summary 2 we can project onto a plane, a cylinder or a cone. For larger scale maps, including topographic quadrangles and the state base map series, conformal projections such as the transverse mercator and the lambert conformal conic are used. Map projections are often named after the mathematician or inventor responsible for arithmetic formula. On conformal conic mappings of spherical domains in this section, we present the derivation of the map projection approximately in the manner it was developed and the formula will be deduced based on the projection formula of. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
The beginning of the book contains substantial introductory information about map projection families and distortions. Cylindrical map projections are one way of portraying the earth. Some common examples are cones, cylinders, and planes. We will taker a closer look at the popular mercator projection and examine how the projection. Certain map projections, or ways of displaying the earth in the most accurate ways by scale, are more wellknown and used than other kinds. We will taker a closer look at the popular mercator projection and examine how the. A developable surface is a geometric shape that can be laid out into a flat surface without stretching or tearing. This booklet provides a conceptual introduction to map projections and geographic reference systems. Use the printable worksheet to pinpoint study points to look.
Types of map projections the number of map projections made possible is limitless, and hundreds have been published. Learn what a map projection is, why they are used and what impact they have on maps gis systems. A working manual available online exploring map projections. Types of maps thematic special purpose, single topic, statistical maps. Projection any component, member, or part that juts out from a building.
This approximates the view of the earth from the sun on the winter solstice at noon in cambridge, ma. The earliest reference in the bibliography is to the classical work of ptolemy, which is circa 150 a. Three of these common types of map projections are cylindrical, conic, and azimuthal. In this lecture, further distinctions of these types are made according to how the viewpoint and viewplane are located with respect to the world coordinate frame. Map projections are created for certain purposes and should be used for those purposes. Worksheets on map projections teachers pay teachers. Or select from any of the 50 states for detailed lakes and. Pseudoconic projection is one of the oldest map types and although they were used by ptolemy, they are seldom seen today. A sound knowledge of map projections and grids requires an understanding of the mathematical nature of projections and the size and shape of the earth, since in our context. Map projections tn 3 given that the earth is a sphere and maps are twodimensional, a mathematical operation called a projection is required to represent the curved surface of the earth on the flat surface of a map. The degree and kinds of distortion vary with the projection used in making a map of a particular area.
Because there is no limit to the number of possible map projections, there can be no comprehensive list. A map projection systematically projects locations from the surface of a spheroid to representative positions on a flat surface using mathematical algorithms. And now we can project and unproject massive quantities of coordinates, transforming them backward and forward from latitude and longitude assuming this or that earth model to overlay precisely with data that are stored in some other coordinate space. Scale same in any direction around a point, but scale changes from point to point. Snyder, pdf, 1997 cegis map projection bibliography usgs, database, 2011 map projections a working manual usgs pp 95, j. Adler, map projections for geodesists, cartographers and geographers, northholland, amsterdam, the netherlands, 1972. Since the mass of the earth is not uniform at all points, and the direction of gravity changes, the. Map projections download ebook pdf, epub, tuebl, mobi.
Although the earth is best represented by a spheroid. A simple and lightweight framework for creating beautiful, interactive vector maps. Spatial thinkingwhy we use maps in geographymap projectiondistortions in map projectionsgoodes. Snyder, 1987 an album of map projections usgs pp 1453, j. Each of the main projection typesconic, cylindrical, and planarare. Conformal projections retain correct angular relations in transfer from globe to map. In the end each and every map projection has a place, and there is no limit to the amount of projections that can be created. Chapter 3 map projections chapter 3 map projections. Large areas tend to look more like they do on the globe than is true for. After decades of using only one map projection, the polyconic, for its mapping program, the u. Sep 20, 2015 description of three different types of map projections. Geodesy, coordinate systems, objectives and map projections. The alaska map e was adapted from a set of transverse mercator projections 8 wide and approximately 18 long, repeated east and west of an arbitrary point of origin until a projection 72 wide was obtained. A stone tablet found in a cave in abauntz in the navarra region of northern spain is believed to.
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