- Identify the elevation of each contour line that crosses line AB. The contour interval is 10 meters, so elevations are 230, 240, 250, 260, 270, 280, 290, 300, 310, and 320 meters.
- Measure the horizontal distance along line AB from point A to where each contour line intersects it, using the map scale (0 to 2 kilometers).
- Plot a point on the grid for each contour line’s elevation at its corresponding distance from A.
- Connect the plotted points with a smooth, curved line to form the topographic profile.
- For the gradient between C and D: Elevation at C is 320 meters, elevation at D is 250 meters. The change in elevation is 320 - 250 = 70 meters. The horizontal distance between C and D is approximately 1 kilometer (1000 meters) based on the map scale. Gradient = change in elevation / horizontal distance = 70 meters / 1000 meters = 0.07 or 7%.
Parent Tip: Review the logic above to help your child master the concept of topographic map worksheet earth science.
