American Meteorological Society Certification Atmospheric Dynamics

Question 1

What force causes wind to deflect to the right in the Northern Hemisphere?

Accepted Answer

Coriolis force

Answer

The Coriolis force, caused by Earth's rotation, deflects moving air to the right in the Northern Hemisphere.

Question 2

In geostrophic balance, which two forces are equal and opposite?

Accepted Answer

Pressure gradient force and Coriolis force

Answer

Geostrophic balance occurs when the horizontal pressure gradient force exactly balances the Coriolis force.

Question 3

What is the Rossby number used to measure?

Accepted Answer

Relative importance of rotation vs. inertia in atmospheric flow

Answer

The Rossby number compares inertial forces to Coriolis forces, indicating when rotation becomes dynamically important.

Question 4

Vorticity in meteorology refers to which property of atmospheric flow?

Accepted Answer

Spinning or rotating motion

Answer

Vorticity measures the local rotation or spin of air parcels within the atmosphere.

Question 5

What does potential vorticity conservation imply for a column of air that stretches vertically?

Accepted Answer

Its relative vorticity increases

Answer

When an air column stretches, relative vorticity must increase to conserve potential vorticity.

American Meteorological Society Certification Practice Test