Definition: Scale

UN - Geographic Information Systems

In cartography, the relationship between the distance on a map and the corresponding distance on the Earth’s surface. Scale is reported as a ratio, for example, 1:100,000, which means that 1 centimetre on the map equals 100,000 centimetres on the Earth’s surface. Since scale is a ratio, a "small scale" map shows a relatively large area, while a "large scale" map shows a small area. More generally, scale refers to the level of observation or enquiry, which may range from micro-scale to macro-scale phenomena.
United Nations, "Handbook on Geospatial Infrastructure in Support of Census Activities", Department of Economic and Social Affairs, Statistics Division, Studies in Methods, Series F No. 103, New York, 2009

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