CONTOURS

Concepts

A contour line is an imaginary line which has the same value all along it. Another term for a contour is an iso-line (meaning same-line).

Contour maps show values of a specific attribute across an area, such as elevation across Antelope Island. An attribute is a characteristic of a feature. An area can have many different values of a single attribute.

An attribute depicted on a contour map is a characteristic of an area that represents “continuous data” meaning that every place has a value of that characteristic. For example, temperature is continuous data… everywhere on Earth has a value for temperature; and every place on Earth’s surface has a value for the attribute “elevation above sea level.” Contour maps of the elevation of Earth’s surface are called topographic maps.

Contours don’t cross. Contours representing different values don’t touch.

Knowing how to read a contour map is a good skill to have because: (a) contoured information is presented to us daily in the forms of weather charts and elevation maps; (b) contour maps help us see the world in 3-dimensions, a different perspective.

Once you have mastered an understanding and skills of contouring, you can take short cuts and explain it to yourselves differently. But, today, humor me. Do it “my” way. It’s a longer way, but it works AND it may work with your students.