An Exercise In Precision Agriculture Module 5 GPS Coordinates and Map Projections

Introduction

    The concept of precision farming is based on access to instantaneous positioning information such as that provided by the Global Positioning System (GPS). Output from most GPS receivers is three dimensional: latitude, longitude and elevation are the values used to describe a position on the surface of an oblated sphere. Most maps of geographically referenced features are projected from the convex surface of the earth onto a scaled plane. For most practical applications of GPS the receiver output must be transformed or mapped from a three dimensional space into two dimensions. Careful consideration must be given to the type of project, appropriate projection and the datum used to describe the earth. Data layering in Geographic Information Systems (GIS) is dependent on defining a single coordinate system for analysis, to which all data sets must conform. The purpose of this educational unit will be to teach practitioners of precision farming the basics of map projections, and the importance of datums as a reference for the transformation.

Class Notes

1. Introduction to Mapping

2. Map Projections

3. Surveying and Mapping

4. Overview of GPS

Slide Presentation

1. Coordinate Conversion

Exercises

Return to Main Module Index