Maps, Etc. What are they, why do we use them, and how do we use them

Globes 3 dimensional representation of the Earth Advantages – exactly as it is, just smaller Disadvantages – not easily portable, since it is a sphere, we can only see half at a time

Maps 2 Dimensional Representations of Earth, or just a portion Advantages: easily portable; can be drawn to any scale Disadvantages: DISTORTION – because you are trying to make a round thing flat

Map Projections Projections help us overcome/reduce distortion Planar (azimuthal) Conical – shows pretty accurate shapes and sizes of landmasses, but distorts the edges [good for showing just one big land mass Cylindrical – Shows the entire Earth, and there are 3 types

Types of Cylindrical Maps Mercator – shapes of continents are distorted at the poles (tops/bottoms), and compressed near equator Homolosine – accurate size and shape, but distances are wrong (interrupted) Robinson – entire earth, good shapes and sizes, but shape of land at the poles is flat (the one on the wall)

Uses/Types of Maps General Reference – topographic Thematic – specific types of information shown, like climate or population Navigation – used by sailors and pilots

Surveying This is what you do to gather the info you need to make a map It all was manual in the past, now we use satellites and airplanes

Satellite Systems Landsat – series of satellites that update the entire Earth every 16 days GOES – Geostationary Operational Environment Satellite

More Satellite and Map Stuff GIS – Geographic Informational System – this layers information on to a map GPS – Global Positioning System – uses 24 Nav Stars to tell you exactly where you are [latitude, longitude, elevation, time]