Map skills: scale, contour lines, gradient and local relief Notes

Scale:

A line (called a linear scale)

A ratio (1:10000)

Words (one unit on the map represents 1000 units in the Earth's surface.

Contour lines:

Relief is the shape of the land, including its height above the sea level and steepness of its slope.

The most effective way to show relief on a map involves the use of contour lines.

Contour lines join places of equal height above sea level.

Every point along a contour line has the same value.

The spacing of the contour lines on a map indicates ints steepness.

Areas where contour lines are close together have steep slopes.

The contour interval is the difference in height between two adjacent contour lines.

Gradient:

Formula : rise/run

Gradient measures the steepness as a fraction or ratio.

It can be calculated by dividing the difference in height between the two points by the horizontal distance between them.

Local relief:

Local relief is the variation in height over a relatively small, defined area.

It is determined by calculating the difference in height between the highest and lowest points in a specified location.

Map skills: scale, contour lines, gradient and local relief