Introducing Geographic Information Systems with ArcGIS: A Workbook Approach to Learning GIS, 3rd Edition

Looking at Coordinate Systems

There is not much to see in the coordinate systems references, in terms of geography. These are the files that store the formulae for converting from one coordinate system to another. What is impressive is how many different ways people have referenced positions on the Earth.

____ 14. Collapse Reference Systems. If you are using ArcGIS version 10.0 Expand Coordinate Systems > Geographic Coordinate Systems. If you are using ArcGIS 10.1 go to

[___] IGIS-Arc\Other_Data

and expand Coordinate Systems\Geographic Coordinate Systems.

____ 15. Expand Europe and look at the Catalog Tree. The point here is that many countries and some cities each have (or had) their own coordinate systems—just as a century ago every locale had its own time system. And these are latitude and longitude systems; consider that each of these lat/lon systems may be projected on to the Cartesian plane in dozens of different ways, producing hundreds of different ways of assigning a pair of numbers of a given point on Earth’s surface. If you double-click on a coordinate system you can view its Properties.

____ 16. Collapse the Europe folder (and the subsequent systems after you explore one or two to get an idea of what is included). Check out North America, where there are fewer geographic coordinate systems, but still a lot. If you right-click on a coordinate system you can view its properties. Check out the planets under Solar System. Based on year 2000 data, what is the diameter ...