Atmosphere & Weather Unit Test

Front 1

Storm Watch

Back 1

When severe weather conditions are possible over a large geographic area, a weather watch is issued. People should plan and have a plan of action.

Front 2

Fujita Scale

Back 2

A scale of tornado severity with numbers from 0 to 6, based on the degree of observed damage

Front 3

Cold Front

Back 3

The front edge of a moving mass of cold air

Front 4

Low Pressure

Back 4

Low-pressure systems have lower air pressure then the areas around it. Air in low-pressure systems come together, or converges and rises. As the air in the center of the low-pressure system rises, it cools and forms clouds and rain.

Front 5

High Pressure

Back 5

High-pressure systems are areas where the air sinks and moves outward. The sinking air is denser than the surrounding air, and the pressure is higher. Cooler, denser air moves out of the center of the high pressure areas toward areas of low pressure and absorbs moisture. Water evaporates, relative humidity decreases and clouds disappear.

Front 6

Anemometer

Back 6

An instrument for measuring the speed of the wind, or of any current of gas

Front 7

Psychrometer

Back 7

An instrument for determining atmospheric

humidity by the reading of two thermometers, the bulb of one being kept

moist and ventilated

Front 8

Air Pressure

Back 8

The measure of the force with which air molecules push on the Earth. The force exerted onto a surface by the weight of the air.

Front 9

Condensation

Back 9

The conversion of a vapor or gas to a liquid

Water that collects as droplets on a cold surface when humid air is in contact with it

Front 10

Convection

Back 10

Heat transfer in a gas or liquid by the circulation of currents from one region to another.

In weather -- warm air rising, cool air sinking. The wind blows to replace warm air rising.

Front 11

Tornado Alley

Back 11

An area of the Great Plains centered on eastern Kansas and Oklahoma and including parts of the surrounding states, where tornadoes are frequent

Front 12

Saturated

Back 12

Holding as much water or moisture as can be absorbed; thoroughly soaked

Front 13

Isobars

Back 13

A line on a map connecting points having the same atmospheric pressure at a given time or on average over a given period

Front 14

Relative Humidity

Back 14

The amount of water vapor present in air expressed as a percentage of the amount needed for saturation at the same temperature

Front 15

Rain Gauge

Back 15

A device for collecting and measuring the amount of rain that falls

Front 16

Weather Barb

Back 16

Indicates the wind direction and wind speed

Front 17

Evaporation

Back 17

The process of a substance in a liquid state changing to a gaseous state due to an increase in temperature and/or pressure.

Front 18

Precipitation

Back 18

The fall of water, ice, or snow deposited on the surface of the Earth from the atmosphere

Front 19

Storm Warning

Back 19

A warning is issued when weather conditions that pose a threat to life and property are happening or are about to happen.

Front 20

Warm Front

Back 20

A warm front forms when a warm air mass follows a retreating cold air mass.

The warm air rises over the cold air, and it's moisture condenses into clouds. Warm fronts often bring drizzly rain and are followed by warm, clear weather.

Front 21

Causes of Winds

Back 21

The sun does not warm the Earth in a uniform manner and causes the air above the surface to be at different temperatures.

Colder, denser air sinks and places greater pressure on the surface of the Earth than warmer, less-dense air, creating areas of high pressure.

Air moves from high pressure to lower pressure. The movement of air caused by differences in air pressure is called wind.

Front 22

Barometer

Back 22

an instrument measuring atmospheric pressure, used especially in forecasting the weather and determining altitude

Front 23

Climate vs. Weather

Back 23

Weather denotes conditions from moment to moment.

Climate denotes characteristic weather patterns occurring over time.

Front 24

Freezing

Back 24

One of the three states of water. The solid state. Water releases energy into its surroundings when it condenses from gas to liquid and when it freezes from liquid to solid or deposits from gas to solid.

Front 25

What type of weather is associated with low pressure?

Back 25

clouds, rain, stormy weather

Front 26

What type of weather is associated with high pressure?

Back 26

dry, clear, sunny

Front 27

What is the ultimate source of energy for wind and weather?

Back 27

The Sun

Front 28

Why does convection make the wind blow?

Back 28

Cold, dense air at the poles creates areas of high pressure at the poles.

Warm less-dense air at the equator forms an area of lower pressure.

This pressure gradient results in global movement of air. The air moves in small circular patterns called convection cells.

Convection currents form where hot matter rises and cooler matter sinks.

Winds blow to replace warm air rising.

Front 29

Four ways meteorologists predict that the weather will be rainy the next day?

Back 29

What weather is like to west

High Humidity

Low pressure

Movements of warm and cold fronts

Front 30

How does water get into the atmosphere?

Back 30

Water reaches the atmosphere as water vapor in three ways: evaporation (liquid water changes into water vapor), transpiration (plants release water into the environment) and sublimation (dry air blows over solid "frozen" water where it is very cold and the pressure is low).

Front 31

When temperature goes down on a humid night, why does dew form on the ground?

Back 31

Cool air can't hold much water. Air becomes saturated when evaporation adds water vapor to the air. The dew point is the temperature at which more condensation than evaporation occurs. When the temperature drops below the dew point, condensation forms and dew develops on surfaces cooler than the dew point.

Front 32

Why does it feel really hot on a humid day?

Back 32

Evaporation is a cooling process, so when we sweat in dry air, our skin will cool. When the air is saturated with water, like on a humid day, evaporation is much slower or does not happen. Sweat does not evaporate which eliminates the cooling effect.

Front 33

Why is easier to predict the weather tomorrow then next week?

Back 33

Conditions like fronts and humidity can change

Front 34

What should you do if you are in danger of getting struck by lightening?

Back 34

Crouch down on balls of feet

Front 35

What are some important things to have during severe weather?

Back 35

water supply

food

radio

flashlight

batteries

Front 36

What drives weather? What is the Earth ultimately trying to do by making the wind blow and rain fall?

Back 36

The Earth is balancing the heat from the equator and the cold of the poles