Weather 1 Flashcards
In what part of the atmosphere does most weather occur?
Troposphere.
The most frequent type of ground based or surface based temperature inversion is produced by
Terrestrial radiation on a clear, relatively still night
In tile Northern Hemisphere, a pilot making a long distance flight from east to west would most
likely find favorable winds associated with high-and low-pressure systems by flying to the
south of a high and to the north of a low
The general circulation of air associated with a high-pressure area in the Northern
Hemisphere is
outward, downward, and clockwise
which us an operational considerations regarding actual air temperature and dewpoint?
The temperature spread decreases as the relative humidity increases
The ratio of the existing water vapor in the air, as compared to the maximum amount that could exist at a given temperature, is called
relative humidity.
What is the process by which ice can form on a surface directly from water vapor on a cold, clear night?
Sublimation
From which measurement of the atmosphere can stability be determined?
Ambient lapse rate.
At approximately what altitude above the surface would you expect the base of cumuliform clouds if the surface air temperature is 77°F and the dewpoint is 53”F?
77 - 53 =24
divide by the degrees F convergence rate of 4.4 f 4.4 per 1,000 ft. 24 / 4.4 - 5.45 So 5.45 thousands of feet, or 5450 feet
At approximately what altitude above the surface would You expect the base of cumuliform clouds if the surface air temperature is 33 C and the dew point is 15C
33 - 15 = 18, and divide by the degrees C convergence rate of
2.5 per 1,000 ft. 18 / 2.5 - 7.2 So 7.2 thousands of feet, or 7,200 feet
The height of the bases of the middle clouds in the middle latitudes ranges from
6,500 to 23,000 feet.
Which middle level clouds are characterized by rain, snow, or ice pellets posing a serious icing problem if temperatures are near or below freezing?
Nimbostratus.
A moist air mass, which is colder than the surface over which it passes, frequently has which of
the above characteristics?:
1. Cumuliform clouds.
2. Stable lapse rate.
3. Unstable lapse rate.
4. Stratiform clouds and fog.
5. Smooth air (above the friction level) and poor visibility.
6. Turbulence up to about 10,000 feet and good visibility except in areas of precipitation.
1,3,6
The weather condition normally associated with unstable air is
good visibility, except in blowing sand or snow.
Frontal waves normally form on
slow-moving cold fronts or stationary fronts.