Maps are called projections because mapmakers have to project a 3d surface onto a 2d map. A working manual available online exploring map projections. Free of distortion at the central meridian at 3646 n. Essentially it is a conformal projection, but is different from the transverse mercator in that the central line of the projection is the satellite groundtrack, along which distortion is minimized. A projected coordinate system is always based on a geographic coordinate system that is based on a sphere or spheroid. Chapter 3 map projections chapter 3 map projections. Learn what a map projection is, why they are used and what impact they have on maps gis systems. A projection developed to accommodate scanning of satellite devices. The beginning of the book contains substantial introductory information about map projection families and distortions.
In this map skills lesson, students discuss map vocabulary and view maps of florida. Some projections require more parameters, described in each projection page at the manual the basemap object has the field proj4string that has the string to be used with proj4 for calculating the projection parameters without using basemap. After decades of using only one map projection, the polyconic, for its mapping program, the u. In truth, the area of map projections is highly complex and the enthusiast can easily lose themselves in many hours of reading. Geological survey usgs now uses several of the more common projections for its published maps. Scale changes in one direction to be offset by scale changes in the other direction. This site is like a library, use search box in the widget to get ebook that you want. Projections and coordinate systems one of the challenges of making maps is to represent the curved surface of the earth on a flat computer screen or a piece of paper. Map projections page 3 introduction to map projections although earth images and map data that you use are typically rendered onto flat surfaces such as your computer screen or a sheet of paper, the earths surface obviously is not flat. Improve your knowledge of map projections in this interactive quizworksheet combo. The mathematics behind map projections are beyond the scope of this introductory overview but see robinson et al. Unlike a geographic coordinate system, a projected coordinate system has constant lengths, angles, and areas across the two dimensions. The main users manual for proj, however, this verticaldatums working notes on the project to support vertical datums in map projections. 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.
Map projections explained a beginners guide youtube. We will taker a closer look at the popular mercator projection and examine how the projection. Every projection has its own set of advantages and disadvantages. Three of these common types of map projections are cylindrical, conic, and azimuthal. Ppt map projections and types powerpoint presentation.
Because there is no limit to the number of possible map projections, there can be no comprehensive list. Geodesy, coordinate systems, objectives and map projections. In cartography, a map projection is a way to flatten a globes surface into a plane in order to make a map. They do the globe projector activity in the xpedition hall and take notes on the different map projections. The art and science of making maps, including data compilation, layout, and design. 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. Spatial thinkingwhy we use maps in geography map projection distortions in map projections goodes. Download our lakes and rivers map of the united states. Understanding map projections landing page for kartoweb. Also concerned with the interpretation of mapped patterns. This booklet provides a conceptual introduction to map projections and geographic reference systems. Worksheets on map projections teachers pay teachers.
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 for these projections. Use this lesson to teach geography classes about types of maps and map projections with great examples and an easytofollow companion worksheet. Map makers through the ages have faced this issue, and developed specialized too. A basic knowledge of the properties of commonly used projections helps in selecting a map that comes closest to fulfilling a specific need. In this geography printable, students identify the objects needed to make a map projection and classify each projection as mercator, polar, or conic. Learning more about map projection and coordinate system concepts. Map projections cartographers have to deal with the problem of making maps of a spherical earth onto a flat surface leads to distortions shape can be distorted distance between two points can increase or decrease.
The field of map projections concerns itself with the ways of translating the curved surface of the earth into a flat map. The map has now an equidistant projection centered at longitude 10 and latitude 50, which is over europe. Map projections a map projection is used to portray all or part of the round earth on a flat surface. Or select from any of the 50 states for detailed lakes and. Students learn about flat maps, which are more portable than globes and allow the viewer to see the entire earth at one time. Here is a series of links to help you learn more about applying map projections and coordinate systems in your work. Manual by lev bugayevskiy and john snyder, ball state. Equivalent or equal area projections a map areaof a given size, a circle three inches in diameter for instance, represents same amount of earth space no matter where on the globe the map area is located. After reading some facts about flat maps, students answer questions. Objectives students understand why we have different types of map projections.
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. Types of map projections the number of map projections made possible is limitless, and hundreds have been published. 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. Which projection is most suitably used for which area. The term projection implies that the ballshaped net of parallels and meridians is transformed by casting its shadow upon some flat, or flattenable, surface.
Although the earth is best represented by a spheroid, the earth is sometimes treated as a sphere. Pdf in this paper, we introduce some known map projections from a model of. This is a summary of map projections that have articles of their own on wikipedia or that are. Young scholars pretend to be cartographers and specify which types of map projections would be the most valuable for their clients.
A projection is a representation of one thing onto another, such as a curved 3dimensional surface like the earth onto a flat 2dimensional map. Spatial thinkingwhy we use maps in geographymap projectiondistortions in map projectionsgoodes. Map projection definition of map projection by the free. A projected coordinate system is defined on a flat, twodimensional surface. All projections of a sphere on a plane necessarily distort the surface in some way and to some extent. Map projections and types 1 map projections and types 2 cartography. By employing retirement planning software to organize your finances, you are going to have an apparent view of your general financial circumstance. The map scale may be expressed in three ways and the pictorial representation of these three types is shown in the figure. 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. The following concepts are addressed in the powerpoint. Many types of map projections have been devised to suit particular purposes. So map projections are chosen based on the purposes of the map.
They discuss the advantages and applications of 5 types of map projections and. Map projections are important in creating maps with map. Com s 477577 notes yanbin jia sep 1, 2016 1 foreshortening ratio two types of projection, parallel and perspective, have been introduced. To represent parts of the surface of the earth on a flat paper map or on. Map projections download ebook pdf, epub, tuebl, mobi. There are many different ways of display the geography of the world, with the robinson and mercator projections amongst the most popular. Certain map projections, or ways of displaying the earth in the most accurate ways by scale, are more wellknown and used than other kinds. Tntmips pro and tntmips free tntmips the map and image processing.
Map scale, coordinate systems, and map projections. The mapmaker must select the one best suited to the needs, reducing distortion of the most important. Types of maps and map projections powerpoint and worksheet. Before addressing the specific types of transformations and the. A stone tablet found in a cave in abauntz in the navarra region of. The grapefruit activity subjects science physical science earth science social studies geography grade 68 912 brief description a fun handson activity makes clear the purposes of different map projections. There are many different types of maps that have different uses. Map projections are created for certain purposes and should be used for those purposes. Click download or read online button to get map projections book now. A map projection is a mathematically described technique of how to represent the earths curved surface on a flat map.
This requires a systematic transformation of the latitudes and longitudes of locations from the surface of the globe into locations on a plane. An introduction to cartography emphasizing map projections. This is a summary of map projections that have articles of their own on wikipedia or that are otherwise notable. Although the earth is best represented by a spheroid, the earth is sometimes treated as a sphere to make mathematical calculations easier. Use the printable worksheet to pinpoint study points to look. Map projections are a systematic transformation of longitudes and latitudes of a location on the surface of the sphere. A map projection is used to portray all or part of the. Because earth has a curving, notquite sphericial shape, planar maps of. Transverse mercator map of a small area in the same high latitudes.
885 826 1570 968 1288 1122 1050 1266 853 1196 283 325 197 748 1654 825 874 77 141 596 1036 650 880 511 1333 896 964 388 168 575 93 822 218 1495