Why is this relevant? How is it used?
The grade of a slope is important to understand in walking, road building, and train track laying.
Calculating gradient in geography
Gradient in geography is different to gradient in maths.
It is always expressed as 1:x, ie 1:4, or 1:1.
the second number in the expression is run/rise, so the way to calculate is:
1:run/rise (where the run and the rise are measured in the same units).
Note that gradient in maths is rise/run, so this is the opposite for this purpose.
Tricks and traps
- Not expressing the gradient in the form 1:x
- using rise over run as in maths
- with a contour map, the contours are likely to be expressed in metres (for the rise) whereas the run is likely to be measured in kms. So, make sure the rise is also in kms (ie 700m = 0.7km) before applying the formula. 1: run/rise
mygeoskills 