Geo206, lecture 1.doc

LECTURE #1 relative location: East lansing vs. Los angeles Great circles run parallel to longitude and connect poles, small circles run with the equator and latitude. *Greenwich = prime meridian**International date line = fiji islands* *Low latitudes: 0-30 *Mid latitudes: 30-50 *High latitudes: 50-90 IN THE BOOK! MAP PROJECTIONS & MAP SCALE! Know the difference between the various kinds of projections and why they are used. Know the difference between small and large scale maps and why each kind may be preferred over the other. Small scale: relatively large area with low level of detail (map of US) Medium scale: relatively medium size area with medium level of detail (map of New York) Large scale: relatively small size with high level of detail (map of a city) Isolines! LOOK IN BOOK! GPS (Global Positioning Device) Network of 24 satellites that orbit the earth every 12 hours?continuously transmit radio signals. By knowing position of satellites + time it takes by which a signal is sent by satellite and received by receiver + speed of PRC = locational reference point. Process called triangulation (using 3 or 4 satellites) GIS (Geographic Information Systems) System of storing, analyzing, and manipulating spatially referenced data, usually in digital form in a computer. Consist of layers of data. Ie: geographic variables, such as vegetation, soils, road networks, surface water, etc. Used in environmental management, municipal planning, business needs. Fig. 02_31