Vocabulary
Water in the Atmosphere
Air Masses
Fronts
Storms
100
The movement of water between the atmosphere and Earth's Surface.
The water cycle
100
What are the three stages of the water cycle. Describe each.
Evaporation- process by which water molecules in liquid water excape into the air as water vapor. Condensation- water vapor in the air become liquid water. Precipation- any form of water that falls from clouds and reaches Earth's surface.
100
Name the common types of precipitation and describe each.
Rain- droplets of water. Hail- Round pellets of ice larger than 5 millimeters in diameter. Snow- Ice crystals (snowflakes). Sleet- Frozen particles of ice smaller than 5 millimeters in diamater. Freezing Rain- Rain that freezes when they touch a cold surface.
100
What is a front? What usually develops along fronts?
The boundary where the air masses meet. Storms often develop along fronts.
100
What are the main kinds of storms?
Thunderstorms Tornadoes Snowstorms Hurricanes
200
The measure of the amount of water vapor in the air.
Humidity
200
What is relative humidity and how is it measured?
Relative humidity is the percentage of water vapor in the air compared to the maximum amount of water vapor the air can hold. It is measured with a psychrometer.
200
What is an air mass?
A huge body of air that has similar temperature, humidity, and air pressure at any given height.
200
Name the four types of fronts.
Cold front Warm front Stationary front Occluded front
200
What is a thunderstorm and how is it formed?
A thunderstorm is a small storm often accompanied by heavy precipitation and frequent thunder and lightning. They form when warm air is forced upward during a cold front.
300
Any form of water that falls from clouds and reaches Earth's surface.
Precipitation
300
How do clouds form?
Clouds form when water vapor in the air condenses to form liquid water or ice crystals.
300
How do scientists classify air masses?
Scientists classify air masses according to temperature and humidity.
300
Describe cold and warm fronts.
Cold front- A fast moving cold air mass overtakes a warm air mass. Warm front- A warm air mass overtakes a slow-moving cold air mass.
300
What is a tornado and how is if formed?
A tornado is a rapidly whirling, funnel-shaped cloud that reaches down from a storm cloud to touch Earth's surface. Tornadoes can form when cold air moves under warm air, forcing it to rise (cold front).
400
A body of air that has similar temperature, humidity, and air pressure at any given height.
Air Mass
400
What is dew point? What two conditions are required for condensation to occur.
Dew point is the temperature at which condensation begins. Cooling of the air, and presence of particles in the air are required for condensation to occur.
400
Name the four types of air masses and describe each according to temperature and humidity.
Maritime tropical- humid and warm- low air pressure. Maritime Polar- humid and cold- high air pressure. Continental tropical- dry and warm- low air pressure Continental Polar- dry and cold- high air pressure.
400
Describe stationary and occluded fronts.
Stationary front- Cold and and warm air masses meet, but neither can move the other. They have a stand-off. Occluded front- A warm air mass is caught between two cooler air masses. The warm air mass is cut off from the ground.
400
What are snowstorms, and how are they formed?
A snowstorm is a storm that is developed like a thunderstorm, except it takes place in extremely cold temperatures. These cold temperatures create snow instead of rain.
500
A violent disturbance in the atmosphere.
Storm
500
What are the three types of clouds. Describe each according to shape and altitude.
Cirrus Clouds- Wispy, feathery clouds- high altitudes (6 kilometers or higher) Cumulus Clouds- fluffy, rounded piles of cotton- at medium altitudes (2 kilometers) Stratus Clouds- flat layers of clouds- low levels (below 2 kilometers)
500
How do air masses move?
Air masses are commonly moved by the prevailing westerlies and jet streams.
500
What are cyclones and Anticyclones? What type of weather to each create?
Cyclone- a swirling center of low air pressure. Low air pressure= clouds, wind and precipitation. Anticyclone- spirling winds with high pressure. High pressure= dry, clear weather.
500
What is a hurricane, and how is it formed? What is the center of a hurricane called?
A hurricane is a tropical cyclone that has winds of 119 kilometers per hour or higher. A hurricane begins over warm ocean water as low-pressure area, or tropical disturbance. If it grows it turns into a tropical storm, and then a hurricane. The center of a hurricane is called the eye A hurricane gets its energy from the warm, humid air over the ocean's surface.
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