Atmosphere
What are the standard pressure and temperature values at sea level?
29.92" Hg and 15 degrees C
The amount of water vapor that air can hold depends on the:
Air temperature
Turbulence and good surface visibility are characteristics of: Stable/unstable air
Unstable air
Clouds are divided into four families according to their:
Height range
During the life cycle of a thunderstorm, which stage is characterized predominately by downdrafts?
Dissipating
What gases (by percentage) primarily make up the earth's atmosphere?
78% Nitrogen, 21% Oxygen, 1% other gases
The term for the temperature at which air must be cooled to become saturated.
Dewpoint
What weather phenomena will a pilot always experience when flying across a frontal boundary?
Change in wind direction
The suffix "nimbus", used in naming clouds, means:
Rain cloud
Which type of cloud has the greatest turbulence?
Cumulonimbus
Troposphere, Stratosphere, Mesosphere, and Thermosphere
What are the processes by which moisture is added to unsaturated air?
Evaporation & sublimation
What measurement can be used to determine the stability of the atmosphere?
Actual lapse rate
Warm, moist air moving over low, flatland areas on clear, calm nights is most conducive to which type of fog?
Radiation fog
These three conditions are necessary for the formation of thunderstorms: High humidity, lifting force, and _________ air.
Unstable
What causes variations in altimeter settings between reporting points?
Unequal heating of the Earth's surface
What may form when the temperature of a collecting surface, like an aircraft wing, is at or below the dewpoint of the adjacent air and the dewpoint is below freezing?
Frost
What decreases the stability of an air mass: warming or cooling from below?
Warming
An air mass moving inland from the coast in winter is conducive to which type of fog?
Advection fog
This type of thunderstorm generally produces the most intense hazard to aircraft:
Squall-line thunderstorm
The wind at 5,000 feet AGL is southwesterly while the surface wind is southerly. This difference in direction is primarily due to:
Friction between the wind and surface
One in-flight condition necessary for structural icing to form is:
A pilot can expect a wind-shear zone in a temperature inversion whenever the windspeed just above the surface is at least:
25 knots
At approximately what altitude above the surface would the pilot expect the base of the cumuliform clouds if the surface air temperature in 82 degrees F and the dewpoint is 38 degrees F?
10,000 feet AGL
What weather phenomenon is always associated with a thunderstorm?
Lightning