Chapters 23 and 24 Review

By Sarah Snoberger

Chapter 23 - Atmospheric Moisture

Humidity -The amount of water vapor in the air

Determined by the temperature or the air

the temperature , the the rate of evaporation

Absolute Humidity : absolute humidity =

Relative Humidity: a common way to express the amount of water vapor in the atmosphere

Psychometer- tool used to measure relative humidity

Mass of air vapor ( grams)

Volume of the air (cubic meters)

Cloud Formation- collections of small water droplets or ice

crystals that fall slowly through the air: water vapor condensed and forms into clouds

Mixing: two bodies of moist air masses mix together and causes the temperature to change

Lifting: the air rises and causes clouds to form due to the temperature drop

Advective Cooling: the temperature of the air mass decreases as the air moves over a cold surface

Types of Clouds

Types of Precipitation Rain: liquid precipitation

Drizzle: the raindrops are smaller than 0.5 mm

Snow: most common type of solid precipitation

Sleet: when rain falls through cool air mass and comes out as clear ice pellets

Hail: solid precipitation in the form of ice chunks

Chapter 24- Weather

Air Masses - a large body or air throughout which

temperature and moisture content are similar

Air Masses

Source Region Type of Air Symbol

Continental dry c

Maritime Moist m

Tropical Warm T

Polar Cold p

Types of Fronts Cold Front: the front edge of a moving mass of

cold air that pushes beneath a warmer air mass like a wedge

Warm Fronts: the front edge of advancing warm air mass that replaces colder air with warmer air

Stationary Front: a front of air masses that moves either very slowly or not at all

Occluded Front: forms when a cold air mass overtakes a warm air mass and lifts the warm air mass off the ground and over another air mass

Cyclones Midlatitude Cyclone: an area of low pressure

that is characterized by rotating wind that moves toward the rising air of the central low-pressure region

Anticyclone: the air sinks and flows outward from the center of high pressure

Reading a Weather Map Uses numerous letters, numbers, and symbols

L = low pressureH= high pressure