topography 101

Topography 101

What is Topography?

• Topography – the study of shapes and features on Earth’s surface

• Differences in Elevation – height above sea level

• Sea Level = 0 feet/meters (base)

How to Read a Topography Map

• Basic Unit = Sea Level

• Benchmark – a point that has been accurately measured for its position/elevation\

• Contour Lines – “circles” that mark different levels of elevation (same interval)

Steepness and Slope

• Contour line interval - the difference in elevation between neighboring contour lines

• Contour lines CLOSE together = VERY steep

• Contour lines FAR away = VERY gradual

Quick Quiz #3The contour interval is 50 meters

1. If the first contour line is at sea level, what is the highest elevation (A)?

2. How high is Point 3?

3. Which side, east or west, is steeper? How do you know?

Warm Up #4

Accuracy vs. Precision.

Accurate.Precise.

Write your own definitions…

Accuracy and Precision

• Accuracy – how close you are to the desired outcome/measurement– CAN BE DONE IN 1 TRIAL

• Precision – how close your measurements are to one another– MUST BE DONE IN

MULTIPLE TRIALS

Accurate or Precise?

Precise!