How to change pitch in waves (IDK how to describe it)

Audacity 2.0.5

Is there a way to make a clip fluctuate between high and low pitch (like a police siren does)?

Sorry about the vague description, I can’t think how to describe it better.

Effect > Change Pitch.
I think you’ll be doing it manually. Select the first segment > Change Pitch up. Select the second segment > Change Pitch down, etc.