American Meteorological Society Certification Atmospheric Dynamics 1 — Questions and Answers
Question 1: What force causes wind to deflect to the right in the Northern Hemisphere?
- Gravity
- Coriolis force (Correct answer)
- Pressure gradient force
- Centrifugal force
Correct answer: Coriolis force
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?
- Gravity and buoyancy
- Friction and Coriolis
- Pressure gradient force and Coriolis force (Correct answer)
- Centrifugal force and gravity
Correct answer: Pressure gradient force and Coriolis force
Geostrophic balance occurs when the horizontal pressure gradient force exactly balances the Coriolis force.
Question 3: What is the Rossby number used to measure?
- Rainfall intensity
- Relative importance of rotation vs. inertia in atmospheric flow (Correct answer)
- Vertical wind shear
- Humidity ratio
Correct answer: Relative importance of rotation vs. inertia in atmospheric flow
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?
- Temperature gradient
- Spinning or rotating motion (Correct answer)
- Moisture content
- Vertical velocity
Correct answer: Spinning or rotating motion
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?
- It warms adiabatically
- Its relative vorticity increases (Correct answer)
- Its absolute vorticity decreases
- Its pressure increases
Correct answer: Its relative vorticity increases
When an air column stretches, relative vorticity must increase to conserve potential vorticity.
Question 6: Which equation describes the conservation of mass in atmospheric dynamics?
- Navier-Stokes equation
- Continuity equation (Correct answer)
- Hydrostatic equation
- Thermodynamic energy equation
Correct answer: Continuity equation
The continuity equation ensures that mass is neither created nor destroyed within an air volume.
American Meteorological Society Certification Atmospheric Dynamics 1
What force causes wind to deflect to the right in the Northern Hemisphere?