Map projections coach grigg ap human geography golf. Because maps are flat, some of the simplest projections are made onto geometric shapes that can be flattened without stretching their surfaces. Some of the different types of map projections include cylindrical, pseudocylindrical, conic, and pseudo conical. There are many different ways of display the geography of the world, with the robinson and mercator projections amongst the most popular. The four parts of map projections are mercator, polar, interrupted, and robinson.
This is a summary of map projections that have articles of their own on wikipedia or that are. Only the tm and utm projections are considered in this paper. The post1973 editions of the alaska map e more nearly approximate an equidistant conic map projection. Pdf there has been a dramatic increase in the handling of geospatial. Projected on a map formed into a cone gives a conical map projection. Learn what a map projection is, why they are used and what impact they have on maps gis systems. Types of projections for designing machines and instruments. Distinguish between different types of maps and mapped information e. The beginning of the book contains substantial introductory information about map projection families and distortions. Map projections ibm informix spatial data types support many map projections. The three classes of map projections are cylindrical, conical and azimuthal. Understanding map projections landing page for kartoweb.
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. The study of map projections is the characterization of these distortions. Students pretend to be cartographers and specify which types of map projections would be the most valuable for their clients. The way i found to do it was opening the file and looking for a suitable option. The first two situations are dealt with in arctoolbox and result in the creation of a projection file. Various types of projected coordinate systems are developed using the above methods and are used in producing different types of maps. Investigating map projections national geographic society. Other projections and grids have been or are being used for mapping and coordination in australia but their use has either been superseded, or is local in extent. Map projections explained a beginners guide youtube. Although the earth is best represented by a spheroid, the earth is sometimes treated as a sphere.
The ellipses show how imaginary circles on the globe are deformed because of a particular. Because there is no limit to the number of possible map projections, there can be no comprehensive list. Projections tend to be the most accurate along the point or line at which they touch the planet. Jan 22, 2011 the usgs has posted a scanned file of john p. Prerequisite skills this booklet assumes that you have completed the exercises. The mapmaker must select the one best suited to the needs, reducing distortion of the most important. This example shows the island of menorca using the utm projection, zone 31n. Learning more about map projection and coordinate system concepts. Best practices for processing and importing maps into the.
This site is like a library, use search box in the widget to get ebook that you. Creating map projections used to be a very hard thing to do. Thematic maps focus on a particular theme or topic. Although they can represent size, shape, distance and directions of the earth features with reasonable accuracy, globes are not.
Types of coordinate systems there are two common types of coordinate systems used in gis. List different types models of diffusion and provide examplesillustrations of each in the realworld. This approximates the view of the earth from the sun on the winter solstice at noon in cambridge, ma. There are 3 generally accepted types of map projections. Some maps are so common that a child would recognize them, while others are used only by professionals in specialized fields. Types of maps and map projections powerpoint and worksheet. The lambert azimuthal equalarea projection is mathematically based on a plane tangent to the earth. Understanding projections and coordinate systems important knowledge to have, especially if you deal with many different sets of. They are basically classified into four groups in accordance with the map projection theory or the types of surfaces that are tangent with the globe. Projections with the name utm are not well supported i. A map is a symbolic depiction emphasizing relationships between elements of some space, such as objects, regions, or themes many maps are static, fixed to paper or some other durable medium, while others are dynamic or interactive. The field of geography relies on many different types of maps in order to study the features of the earth. Scale changes in one direction to be offset by scale changes in the other direction. A map projection systematically projects locations from the surface of a spheroid to representative positions on a flat surface using mathematical algorithms.
In cartography, a map projection is a way to flatten a globes surface into a plane in order to make a map. By employing retirement planning software to organize your finances, you are going to have an apparent view of your general financial circumstance. The chronology is summarized in tables 2 and 3 and needs only a few additional remarks. The app processes a map by rasterizing and tiling it on import.
Idls map function allows you to view more than 30 different map projections. Distortion ellipses help us to visualize what type of distortion a map projection has caused, how much distortion occurred, and where it occurred. This booklet provides a conceptual introduction to map projections and geographic reference systems. Many common map projections are classified according to the projection surface used. Sep 20, 2015 description of three different types of map projections. Pdf overview, classification and selection of map projections for. In truth, the area of map projections is highly complex and the enthusiast can easily lose themselves in many hours of reading. What are the four types of map projections answers. These are based on the types of geometric shapes that are used to transfer features from a sphere or spheroid to a plane. Improve your knowledge of map projections in this interactive quizworksheet combo. The spatial or map extent covered by the dataset often referred to as the spatial domain learning more about coordinate systems. Some of the most common types are political, physical, topographic, climate, economic, and thematic maps. Map projections tn 6 a map is a representation of all or part of the earth drawn on a flat surface at a specific scale.
Map projections is about presenting the round earth on a flat surface. All maps, such as wall maps and those in atlases, specify the type of projection. This requires a systematic transformation of the latitudes and longitudes of locations from the surface of the globe into locations on a plane. They then examine the distortions of different map projections while comparing land and ocean to its representation on a globe. The types of thematic maps on this page use symbols, lines, and dots to display data. General reference, topographical, thematic, navigation charts and cadastral maps and plans. The degree and kinds of distortion vary with the projection used in making a map of a particular area. Map projections displaying the earth on 2 dimensional maps the world from space projection from esri, centered at 72 west and 23 south. In the next dialog box, browse to your workspace and select snow. Map projections types and distortion patterns geokov. The information contained in this document is the exclusive property of environmental systems.
After decades of using only one map projection, the polyconic, for its mapping program, the u. This might be acceptable when working with latitudelongitude data, but will get you in trouble i. Types of map projections many types of map projections are being used for map making. Planar, azimuthal or zenithal projection conic projection cylindrical projection mathematical or conventional projection. Projections and transformations feature because we are working with a vector file project. Investigating map projections students use oranges to investigate the effects of changing a 3d surface to a 2d surface. As an example of how it works, lets look at the entries for the british national grid mentioned in map projections. But proper understanding of the concepts and access to the right tools will make it much easier to deal with projections. Avenza maps is capable of importing and displaying georeferenced maps in several different formats. 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. The following table lists a representative sample of the map projections supported by the ibm informix spatial data types. The three major types of projections developed from this method are the cylindrical, planar, and conic.
This is a digital copy of a book that was preserved for. One centimeter on a map projection is different in different areas of the map, and this is what creates its limitations. Click on the edit button and define the coordinate system as geographic, nad 1927 1976 definition. A sound knowledge of map projections and grids requires an understanding of the.
Sep 30, 2016 choosing a map projection the choice of map projection is made to give the most accurate possible representation of the geographic information, given that some distortion is inevitable. Click download or read online button to get map projections book now. The speed and result of processing will vary depending on the type of file used and the size and dimensions. A map projection is used to portray all or part of the round earth on a flat. They do the globe projector activity in the xpedition hall and take notes on the different map projections. The information contained in this document is subject to change without notice. Projections and coordinate systems are a complicated topic in gis, but they form the basis for how a gis can store, analyze, and display spatial data. Spatial thinkingwhy we use maps in geography map projection distortions in map projections goodes. Technically all maps are projections because the earth is curved everywhere. The earliest reference in the bibliography is to the classical work of ptolemy, which is circa 150 a. Identify types of scale and projections used in mapmaking.
It is the only projection that can accurately represent both areas and true direction from the center of the projection. Today the lambert conformal conic projection has become a standard projection for mapping large areas small scale in the midlatitudes such as usa, europe and australia. Three large families of map projection, plus several smaller ones, are generally acknowledged. Map projections download ebook pdf, epub, tuebl, mobi. Map projections or coordinate reference system crs often cause a lot of frustration when working with gis data. Map projections massachusetts institute of technology. Nov 27, 2015 read on as we take a look at some of the different map types and their uses. The above methods are various types of projection systems used in map preparation. Some common examples are cones, cylinders, and planes. The earths surface projected on a map wrapped around the globe as a cylinder produces the cylindrical map projection. Apr 25, 2017 what are the different types of map projections.
Maps were devised because they are much easier to use, store, and transport than globes, and they facilitated the development of much larger scaled representations than was the case with a globe. No projection allows us to flatten the globe without distorting it. Slideshare uses cookies to improve functionality and performance, and to. Nature of geographic informationan open geospatial textbook.
This is a summary of map projections that have articles of their own on wikipedia or that are otherwise notable. Map makers attempt to transfer the eartha round, spherical globeto flat paper. Scale increases perpendicular to the radii toward the periphery. Geol 3050 gis for geologists exercise 5 exercise 5. You will also get information of their application area and also advantages and disadvantages.
A global or spherical coordinate system such as latitudelongitude. Map projections a map projection is used to portray all or part of the round earth on a flat surface. Well discuss the types of files allowed and the advantages of each. Which projection is most suitably used for which area. The location shape size of the region to be mapped the theme or purpose of the map 37 38. It is also modeled more accurately as an oblate spheroid or an ellipsoid. It has also become particularly popular with aeronautical charts such as the 1.
Three of these common types of map projections are cylindrical, conic, and azimuthal. This topic shows how to use the map function to view projections, and how to warp a map image to a map projection. It explains main types of projections in well mannered way using figure for each one. There is no limit to the number of possible map projections 1 projections are a subject of several pure mathematical fields, including differential geometry, projective geometry, and manifolds. We will taker a closer look at the popular mercator projection and examine how the projection. Use this lesson to teach geography classes about types of maps and map projections with great examples and an easytofollow companion worksheet. Each shape can touch or cut through the earth at any point and from any angle, dramatically changing the area that is most accurate and the shape of the finished map. Students will work individually to complete a kim chart using lesson vocabulary.
This article describes what the projection methods are there for drawing and design machine elements and instruments. Here is a series of links to help you learn more about applying map projections and coordinate systems in your work. Types of map projections the number of map projections made possible is limitless, and hundreds have been published. According to the icsm intergovernmental committee on surveying and mapping, there are five different types of maps. Use the printable worksheet to pinpoint study points to look. Map projections are often named after the cartographer who developed them, after the method used in the projection, or a combination of both. All projections of a sphere on a plane necessarily distort the surface in some way and to some extent. Mapmakers have developed hundreds of map projections, over several thousand years.
Types of map projections there are three main types of map projections. 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. This booklet provides a conceptual introduction to map projections. This document gives the key properties, characteristics, and preferred uses of.
Each of the main projection typesconic, cylindrical, and planarare. Different types of projection systems used in gis maps. These are often referred to arcgis 10 what are map projections. However, map projection refers specifically to a cartographic projection. Geological survey usgs now uses several of the more common projections for its published maps. A map projection is used to portray all or part of the round earth on a flat surface. About map projectionthe classification of map projection.
Spatial thinkingwhy we use maps in geography map projectiondistortions in map projections goodes. Although the earth is best represented by a spheroid, the earth is sometimes treated as a sphere to make mathematical calculations easier. A specific map projection and coordinate system is chosen based on the location of study area and application of map. Every projection has its own set of advantages and disadvantages. Feb 21, 2011 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. Comparing map projections to the globe answer key analyze the maps on the map projections handout and a globe to complete the charts below. The projection selected for a particular map depends on the relative importance of different types of distortion, which often depends on the purpose of the map.