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Understanding Map Projections Understanding Map Projections GIS by ESRI ™ Copyright © 19942000 Environmental Systems Research Institute, Inc All rights reserved Printed in the United States of America The information contained in this document is the exclusive property of Environmental Systems Research Institute, Inc This work is protected under United States copyright law and other international copyright treaties and conventions No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or by any information storage or retrieval system, except as expressly permitted in writing by Environmental Systems Research Institute, Inc All requests should be sent to Attention: Contracts Manager, Environmental Systems Research Institute, Inc , 380 New York Street, Redlands, CA 92373-8100, USA The information contained in this document is subject to change without notice US GOVERNMENT RESTRICTED/LIMITED RIGHTS Any software, documentation, and/or data delivered hereunder is subject to the terms of the License Agreement In no event shall the U S Government acquire greater than RESTRICTED/LIMITED RIGHTS At a minimum, use, duplication, or disclosure by the U S Government is subject to restrictions as set forth in FAR §52 227-14 Alternates I, II, and III (JUN 1987); FAR §52 227-19 (JUN 1987) and/or FAR §12 211/12 212 (Commercial Technical Data/Computer Software); and DFARS §252 227-7015 (NOV 1995) (Technical Data) and/or DFARS §227 7202 (Computer Software), as applicable Contractor/Manufacturer is Environmental Systems Research Institute, Inc , 380 New York Street, Redlands, CA 92373- 8100, USA ESRI and the ESRI globe logo are trademarks of Environmental Systems Research Institute, Inc , registered in the United States and certain other countries; registration is pending in the European Community ArcInfo, ArcGIS, GIS by ESRI, and the ESRI Press logo are trademarks of Environmental Systems Research Institute, Inc Other companies and products mentioned herein are trademarks or registered trademarks of their respective trademark owners attribution.p65 8 01/06/2001, 1:46 PM Contents CHAPTER 1: GEOGRAPHIC COORDINATE SYSTEMS ....................1 Geographic coordinate systems ............................................................................... 2 Spheroids and spheres ............................................................................................. 4 Datums ...................................................................................................................... 6 North American datums ............................................................................................ 7 CHAPTER 2: PROJECTED COORDINATE SYSTEMS ........................9 Projected coordinate systems ................................................................................. 10 What is a map projection? ...................................................................................... 11 Projection types ...................................................................................................... 13 Other projections .................................................................................................... 19 Projection parameters ............................................................................................. 20 CHAPTER 3: GEOGRAPHIC TRANSFORMATIONS ........................23 Geographic transformation methods ..................................................................... 24 Equation-based methods ........................................................................................ 25 Grid-based methods ............................................................................................... 27 CHAPTER 4: SUPPORTED MAP PROJECTIONS ..............................29 List of supported map projections ......................................................................... 30 Aitoff........................................................................................................................ 34 Alaska Grid ............................................................................................................. 35 Alaska Series E ........................................................................................................ 36 Albers Equal Area Conic ........................................................................................ 37 Azimuthal Equidistant ............................................................................................. 38 Behrmann Equal Area Cylindrical .......................................................................... 39 Bipolar Oblique Conformal Conic ......................................................................... 40 Bonne ...................................................................................................................... 41 Cassini–Soldner ....................................................................................................... 42 Chamberlin Trimetric .............................................................................................. 43 Craster Parabolic ..................................................................................................... 44 Cylindrical Equal Area ............................................................................................ 45 Double Stereographic ............................................................................................. 46 Eckert I .................................................................................................................... 47 mptoc.p65 3 01/06/2001, 12:31 PM Eckert II ................................................................................................................... 48 Eckert III ................................................................................................................. 49 Eckert IV ................................................................................................................. 50 Eckert V ................................................................................................................... 51 Eckert VI ................................................................................................................. 52 Equidistant Conic .................................................................................................... 53 Equidistant Cylindrical ............................................................................................ 54 Equirectangular ....................................................................................................... 55 Gall’s Stereographic ................................................................................................ 56 Gauss–Krüger .......................................................................................................... 57 Geocentric Coordinate System ............................................................................... 58 Geographic Coordinate System .............................................................................. 59 Gnomonic ............................................................................................................... 60 Great Britain National Grid .................................................................................... 61 Hammer–Aitoff ........................................................................................................ 62 Hotine Oblique Mercator ....................................................................................... 63 Krovak ..................................................................................................................... 64 Lambert Azimuthal Equal Area............................................................................... 65 Lambert Conformal Conic ...................................................................................... 66 Local Cartesian Projection ...................................................................................... 67 Loximuthal .............................................................................................................. 68 McBryde–Thomas Flat-Polar Quartic ..................................................................... 69 Mercator .................................................................................................................. 70 Miller Cylindrical ..................................................................................................... 71 Mollweide ............................................................................................................... 72 New Zealand National Grid ................................................................................... 73 Orthographic ........................................................................................................... 74 Perspective .............................................................................................................. 75 Plate Carrée ............................................................................................................. 76 Polar Stereographic ................................................................................................. 77 Polyconic ................................................................................................................. 78 Quartic Authalic ...................................................................................................... 79 Rectified Skewed Orthomorphic ...........................................................................
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