GGRB32H3 Study Guide - Final Guide: Cnes, Asso
Document Summary
Geographic information systems: a definition - computer systems enabling creation, collection, compilation, analysis, and visualization of geographical or spatially- referenced data and subsequent hypotheses generation and/or decision-making using that data for a wide variety of purposes. Geographic coordinate systems angular coordinates: latitude (north-south): 90 (s) to +90 (n) longitude (east-west): -180 (s) to. +180 do not translate to consistent linear units over the surface of the earth: 1 east-west at the equator much larger than 1 east-west at the poles. Different systems defined by varying models of earth"s shape and/or how the ellipsoid model relates to specific positions on the earth. In part, there"s no way to flatten a useful model of the shape of the earth onto a flat surface (i. e. , a map) without some compromises. For different regions and/or mapping purposes, different projections provide better or worse results. Different needs result in data stored using different coordinate systems and you need to be able to convert between them.
