Atmosphere
Atmospheric Pressure
Winds & Currents
Atmospheric Stability
Air Masses
100
The composition of the earths atmosphere consists of what three elements?
78% Nitrogen
21% Oxygen
1% Trace Gases
100
Atmospheric pressure is measured in inches of?
Mercury (Hg)
Standard pressure is 29.92 inches of Hg
100
What directions does air circulate around an area of high pressure and low pressure in the Northern Hemisphere?
Anticyclonic circulation (clockwise) occurs around a an area around high pressure and Cyclonic circulation (counterclockwise) occurs around an area of low pressure in the Northern Hemisphere.
100
The combination of ___________ and ____________ determine the stability of the air and the resulting weather.
The combination of MOISTURE and TEMPERATURE determine the stability of the air and the resulting weather.
100
What are the four types of fronts?
Warm
Cold
Stationary
Occluded
200
Inside the troposphere, the average temperature decreases at a rate of about?
2 Degrees Celsius every 1,000 feet of altitude gain
Lapse Rate
200
Inside the troposphere the pressure decreases at a rate of about?
1" per 1,000 feet of altitude gain
200
What are heat-driven cycles called that occur in the air that are caused by a difference in temperature, often due to a differing proximity to a heat source?
Convective Currents
200
What is the atmospheric anomaly called when the temperature of the air rises with an increase in altitude.
Inversion
200
What are the three stages of a thunderstorm?
Cumulus Stage
Mature Stage
Dissipating Stage
300
What is the primary factor contributing to atmospheric circulation?
Uneven heating of the Earth's surface.
300
What is the ISA (Int'l Standard Atmosphere) pressure and temperature?
29.92" Hg
15 deg. Celsius (59 deg. Fahrenheit)
300
What is a sudden, drastic change in wind speed and/or direction over a very small area?
Wind Shear
300
What is dew point?
The temperature at which a body of air can hold no more moisture.
When the temperature of the air is reduced to the dew point, the air is completely saturated and moisture begins to condense in the form of fog, dew, frost, clouds, rain or snow.
300
What are the three types of ice?
Clear Ice
Rime Ice
Mixed Ice
400
The force created by the rotation of the Earth is known as?
The Coriolis Force
400
At higher altitudes the atmospheric pressure is ____________ causing takeoff and landing distances to _______________ and climb rates to _____________.
At higher altitudes the atmosphere pressure is LOWER causing take off and landing distances to INCREASE and climb rates to DECREASE.
400
What is the most sever type of low level windshear called that can last 5-15 minutes and produce downdrafts up to 6,000 feet per minute?
Microburst
400
What is the rate of temperature and dew point convergence?
4.4 deg. Fahrenheit (2.5 deg. Celsius) per 1,000 feet
400
What is a fast moving cold front that catches up with a slow-moving warm front called?
Occluded Front