The amplitude would double. The frequency would double. The amplitude would decrease by half. The frequency would decrease by half.
I gave my students this multiple choice question: Rossby waves are slow-moving, long ocean waves. What feature of a Rossby wave would change if the wavelength was doubled?

Only one answer is correct among these 4 choices:
- The amplitude would double.
- The frequency would double.
- The amplitude would decrease by half.
- The frequency would decrease by half.

Could you tell me which one is correct?

The frequency would decrease by half.