Map Projections and Coordinate Systems


What are Map Projections?

The shape of the earth is roughly spherical wheres as maps are two dimensional.   Map projection is a set of techniques designed to depict with reasonable accuracy the spherical earth in a two-dimensional (i.e. flat) media.  Map projection types are created by an imaginary source of light projected inside the earth.  Different map projection families have that source of “light” projected from a different angle within the earth.

Introduction to Map Projections

Common Map Projections

Exploring Map Projections
Created using D3, Map Projection Transitions provides an excellent way to visualize a wide range of map projections.

What is a Map Projection?
How is the 3D surface of the earth modeled onto a 2D surface?  The basic concepts behind map projections explained.

Common Map Projections
What are some common map projections and what agencies use them?

Map Projections: A Working Manual Available Online
Scanned file from the USGS of John P. Snyder’s 1987 “Map Projections: A Working Manual” online in PDF  and DjVu format.

State Plane Coordinate System 
FIPs, Zones and the Fifty States, learn all about the SPCS.

Working With Map Projections and Coordinate Systems

How to Calculate the Boundaries of an UTM Zone
Learn how to calculate the eastern and western boundaries of a UTM zone.

Further Map Projection and Coordinate System Resources

FAQs for questions about the National Geodetic Survey.

NGS Software
NOAA’s NGS has several datum and projection software applications available for free downloading.

Picture Gallery of Map Projections
Clickable web site that lets you see how the different map projections look based on a normal, transverse, oblique or normal-wide view.

TatukGIS Datum and Projection Calculator
Free download from TatukGIS. This application reprojects the coordinates of a point from one system to another.

UTM Grid Zones
Map of the world overlayed with UTM grids. Find out the UTM grid your area is located in. Tutorials to help you understand the various projection and coordinate systems. Also find conversion tools to convert datasets from one system to another.

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