Chapt. 18 & 20

If the water vapor content of air remains constant, lowering air temperatures causes what?
When the water-vapor content of air remains constant, lowering air temperature causes an increase in relative humidity, and raising air temperatures causes a decrease in relative humidity.
What is true about warm, saturated air?
Warm saturated air contains more water vapor than cold air.
Compared to clouds, fogs are…
clouds with their bases at or near the ground
Air that has reached its water vapor capacity is said to be…
saturated
Hurricanes form in tropical waters between the latitudes of…
5 and 20 degrees north and south latitude
What type of front forms when the surface position of the front does not move?
Stationary front
The process of converting a liquid to a gas is known as…
Evaporation
The boundary that separates different air masses is known as…
a front
What is the first sign of an approaching warm front?
the appearance of cirrus clouds
What type of shape is associated with a middle latitude cyclone?
wave shape
What is the dry adiabatic rate?
the rate of cooling or heating in unsaturated air
A low cloud that blankets the sky and often generates precipitation is called…
a Nimbostratus
Which terms is used to describe clouds of middle height?
Alto
The process by which water vapor changes directly into a solid is called…
deposition
An immense body of air characterized by similar properties at any given altitude is known as…
an air mass
Which of the following refers to the temp to which air would have to be cooled to reach saturation?
Dew point
Water vapor makes up makes up what fraction of atmospheric gases?
0 to 4 percent
Which gas is the most important for understanding atmospheric processes?
Water vapor
The ratio of air’s water vapor content to its capacity to hold water vapor at that same temperature is the…
relative humidity
Which of the following refers to the energy that is stored or released during the change of state of water?
latent heat