Intro To Contour Lines

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Question 1: Is “sea level” the height of an ocean's surface that is near a coast?

• No

• Yes

Answer explanation

Yes. It’s the mean (average) height.

Is all dry land above sea level?

• No

• Yes

Answer explanation

No. For example, much of New Orleans is below sea level.

Do contour lines exist in Nature?

• No

• Yes

Answer explanation

No. They are imaginary, so do not exist in Nature. They’re on maps.

Is the “contour interval” the horizontal distance between contour lines?

• No

• Yes

Answer explanation

No. It's the vertical distance. It's the same for every contour line in a given set of contour lines.

If we could see contour lines on the side of a hill, would they be horizontal?

• No

• Yes

Answer explanation

Yes. They would all be horizontal and parallel to sea level.

If a number is missing on a contour line, can we calculate its value?

• No

• Yes

Answer explanation

Yes. By using the value of other contour lines and the contour interval.

On a map of a steep hill, would we expect the contour lines to be close to each other?

• No

• Yes

Answer explanation

Yes. The steeper the hill, the closer the contour lines will be.

On a map of a horizontal beach, would we expect the contour lines to be close to each other?

• No

• Yes

Answer explanation

No. The shallower the slope, the farther apart the contour lines will be.