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Geography of Canada. Geographic Skills : The Map Scale. What is a map scale. Map scale is the relationship between two points measured on a map and the same two points measured on the ground .
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Geography of Canada Geographic Skills : The Map Scale
What is a map scale • Map scale is the relationship between two points measured on a map and the same two points measured on the ground. • The concept of a map scale will be used throughout the course, so be sure that you understand this section.
Why scale is important on maps (and other objects). The following are actual stories told by travel agents A man called, furious about a Florida package we did. I asked what was wrong with the vacation in Orlando. He said he was expecting an ocean-view room. I tried to explain that is not possible, since Orlando is in the middle of the state. He replied, "Don't lie to me. I looked on the map and Florida is a very thin state." I got a call from a man who asked, "is it possible to see England from Canada?" I said, "No." He said "but they look so close on the map." A nice lady just called. She needed to know how it was possible that her flight from Detroit left at 8:20 a.m. and got into Chicago at 8:33 a.m. I tried to explain that Michigan was an hour ahead of Illinois, but she could not understand the concept of time zones. Finally I told her the plane went very fast, and she bought that! http://www.mustsharejokes.com/page/Funny+True+Stories
Three types of map scale • We can relate map and ground distances using three types of scale. 1- A Verbal scale states, in words, the relationship between a map distance and a ground distance. “One centimetre represents 16 kilometres” In this example the one centimetre is on the map, and that one centimetre represents 16 kilometres on the ground. Verbal scales are easy to use but only if the map reader understands the language in which they are written.
2- A Linear scale is a usually drawn as a bar which shows directly on the map the equivalent ground distance. In this type of scale the bar is divided into 1 cm sections with each section representing 1 kilometre on the ground. The Linear scale is easy to use but forces the map reader to work in the units of that scale. This is often a problem for tourists coming from a metric based country who are travelling in an imperial based country (and vice versa).
3- The third type of scale is called a Representative Fraction (Ratio scale). A Representative Fraction, or RF, shows the relationship between any type of unit on the map and one of the same unit on the ground. RFs may be written as a fraction or as a ratio; “1/24 000” or “1:24 000” In this example, one unit of any length (one mm, one cm, one inch, one foot, etc.) on the map represents 24,000 of those same units on the ground. The RF is the most flexible scale because you are not tied to any one type of units. You may work in any unit you choose, either metric, English, or other.
