Maps and Modern tools How Do Geographers Describe Where Things Are?
Patterns • Geographers look for patterns.
Patterns • When they find similarities or differences between places, they ask why.
In order to explain these differences, geographers must have tools to help answer WHERE something is.
Cartography • Definition: The science of map-making • Two reasons to use maps: • As a reference tool (to keep us from getting lost) • As a communications tool (to explain where something is distributed)
Map Scales • Measured in three ways: • Ratio (ex. 1 inch=25,000 inches) • Written Scale (ex. 1 inch=50 miles) • Graphic Scale (ex. bar line – see picture on left)
Map Projection • Projection – Transferring locations on Earth’s surface to a flat map http://www.1worldglobes.com/images/Globes/Discovery-Globe-thumb.jpg
Projection • Can be difficult, as most maps are distorted (sphere vs. flat paper) • BUT…globes aren’t portable or practical
Projection cont’d • 4 types of distortions • Shape • Distance (Between two points) • Relative size (may appear larger or smaller than it actually is) • Direction (from one place to another) C:\Users\stevensaa\Desktop\mirror_distortion_1_th.gif
Satellite-Based Maps • GPS – Global Positioning System • Determines the precise position of areas on Earth • 3 Elements: • Numerous satellites (remote sensing) • Tracking stations (controls the satellites) • Receiver (used to pinpoint location) http://www.nist.gov/pml/div688/grp40/images/GPS_Constellation_2.gif
Satellite cont’d • GIS – Geographic Information System) • Computer system that can capture, store, analyze, and display geographic data • More accurate • Can show relationships between different kinds of information http://gothamist.com/attachments/jake/2006_6_bestofmap1.jpg