Which of the following refers to primary circulation?
- General circulation of the atmosphere

Which of the following refers to secondary circulation?
- Migratory high and low-pressure systems

Which of the following refers to tertiary circulation?
- Land-sea breezes

Air-flow is initiated by the:
- Pressure gradient force

A horizontal motion of air relative to Earth's surface is known as:
- Wind

Normal sea level pressure has a value of:
- 1013.2 millibars or 29.92 inches of mercury in the barometer

The average height of a column of mercury (Hg) in a barometer at sea level is:
- 760 mm (26 cm)

An instrument used to measure air pressure is:
- An aneroid barometer

An increase in air pressure will cause the mercury in a barometer to:
- Rise

The normal range for air pressure at sea level is:
- 980 to 1050 mb

As air pressure increases, the speed of the molecules in a mass of air:
- Increases, and the air pressure increases

Which of the following describes the pressure gradient force?
- It drives air from areas of higher to lower barometric pressure.

An isoline of equal pressure plotted on a weather map is known as:
- An isobar

Air flows ___ a surface high pressure area because the density of the air in the high-pressure zone is ___ than that of the surrounding air.
- Out of, more dense

If Earth did not rotate, air would flow:
- Perpendicular to the isobars, straight through the isobars

Which of the following is true of high-pressure areas?
- Air descends and diverges within high-pressure systems

On a weather map of air pressure, what can you infer from a closer spacing of isobars?
- A steep pressure gradient creating a faster flow of air

Which of the following describes the Coriolis force?
- It causes the apparent deflection of winds from a straight path.

The deflection produced by the Coriolis effect is caused by:
- The fact that Earth's rotation decreases in speed towards the poles

In the absence of friction, the combined effect of the Coriolis force and the pressure gradient force produces geostrophic winds at high altitudes above the ground.

The Intertropical Convergence Zone is characterized by:
- Convergence and uplift of warm surface air

Between 20 degrees and 35 degrees north latitude and 20 degrees to 35 degrees south latitude are the world's semi-arid desert regions.

Winds that blow predominantly from the northeast and southeast are the:
- Trade winds

The dominant surface winds from the subtropics to high latitudes are the:
- Westerlies

If you were between 40 degrees and 50 degrees north latitude and you wanted to stand with the average winds blowing in your face, you would stand facing:
- West

Airflow in a Northern Hemisphere high-pressure zone is:
- Downward, outward, and clockwise

Within the upper-air westerly wind flow are great waving undulations known as:
- Rossby waves that involve contact between cooler and warmer air masses

Land-sea breezes are caused by:
- Onshore (toward the land) air flows that develop in the afternoon as the land heats faster than neighboring water surfaces

Mountain-valley breezes are caused by:
- Warm air rising upslope during the day and cooler air descending the slopes at night

The winds that blow off the ice sheets of Antarctica and Greenland are:
- Katabatic winds

Monsoonal winds are:
- Regional wind systems that seasonally vary

Ocean currents are produced by:
- Friction, Coriolis force, and water density differences only