Meteo(WeatherPatterns) Flashcards
How will frost on the wings of an airplane affect takeoff performance.
A. Frost will disrupt the smooth flow of air over the wing, adversely affecting its lifting capability.
B. Frost will change the camber of the wing, increasing its lifting capability.
C. Frost will cause the airplane to become airborne with a higher angle of attack, decreasing the stall speed.
A.
Frost disrupts the smooth airflow over the wing and can cause early separation of the airflow, resulting in a loss of lift. Frost does not significantly change the camber (B.), but it can disrupt the airflow and decrease the lift. The decreased lift caused by frost can cause the stall speed to increase, not decrease(C.).
Every physical process of weather is accompanied by, or is the result of, a
A. movement of air
B. pressure differential
C. heat exchange
C.
EVERY PHYSICAL PROCESS OF WEATHER such as heating cooling, evaporation, and condensation, IS CAUSED BY, or is the result of, A HEAT EXCHANGE.
(A.) and (B.) are wrong because air movement and pressure differential are not always involved in the physical processes of weather.
A temperature inversion would most likely result in which weather condition?
A. Clouds with extensive vertical development above an inversion aloft.
B. Good visibility in the lower levels of the atmosphere and poor visibility above an inversion aloft.
C. An increased in temperature as altitude is increased.
C.
Normally, temp decreases with altitude. During an inversion , cooler air is trapped beneath a warmer layer of air. Therefore, temp increases with altitude.
A. is wrong since inversion occur in stable air, and vertical development of clouds require unstable air.
B. is incorrect because weather and pollutants are trapped beneath inversions, and visibility near the surface is usually poor.
Th most frequent type of ground or surface-based temperature inversion is that which is produced by
A. terrestrial radiation on a clear, relatively still night.
B. warm air being lifted rapidly aloft in the vicinity of mountainous terrain.
C. the movement of colder air under warm air, or the movement of warm air over cold air.
A.
An inversion commonly forms on clear, cool nights when the ground radiates heat and cools faster than the overlying air.
B. and C. are not examples of surface-based temperature inversion.
B. describes orographic lifting of air over rising terrain and C. describes a cold front inversion.
Which weather conditions should be expected beneath a low-level temperature inversion layer when the relative humidity is high?
A. Smooth air, poor visibility, fog, haze, or low clouds.
B. Light wind shear, poor visibility, haze, and light rain.
C. Turbulent air, poor visibility, fog, low stratus type clouds, and shower precipitation.
A.
Low-level temperature inversions normally occur in stable, smooth air, with poor visibility due to trapped pollutants which are commonly referred to as condensation nuclei. In addition, high humidity tends to cause formation of fog and low clouds.
B and C are not entirely correct, because wind shear, turbulence, and showery precipitation are uncharacteristic conditions in the stable air below the inversion layer.
What is meant by the term “dewpoint”?
A. The temperature at which condensation and evaporation are equal.
B. The temp at which dew will always form.
C. The temp to which air must be cooled to become saturated.
C.
When air is cooled to its dewpoint, it can hold no more moisture, and is said to be saturated. A. is incorrect because dewpoint is not a measure of condensation or evaporation. B. is wrong because thee formation of dew requires the surface temperature of objects to cool below the dewpoint of the surrounding air.
The amount of water vapor which air can hold depends on the
A. dewpoint
B. air temp
c. stability of the air
B.
The amount of moisture in the air primarily depends on the temp.
For example, warm air can hold more moisture than cool air.
The dewpoint (A.) is the temp at which the air reaches saturation
C. is wrong because stability of the air does not directly affect the moisture content.
