2Nd Semester Earth Science Chapter 12 Vocabulary

Front 1

What is weather?

Back 1

Weather is short-term variations in atmospheric phenomena that interact and affect the environment and life on Earth

Front 2

What is climate?

Back 2

Climate is the long-term average of variations in weather for a particular area.

Front 3

How many years of weather data does it take to determine an area's climate?

Back 3

over 30 years average

Front 4

What is an air mass?

Back 4

An air mass is a large volume of air that has the same characteristics, such as humidity and temperature, as its source region.

Front 5

What is a source region?

Back 5

A source region is the area over which the air mass forms

Front 6

What are the three types of air masses?

Back 6

Arctic, tropical, and polar

Front 7

Tell about arctic air masses.

Back 7

Arctic- Earth's ice and snow covered surfaces above 60 degrees N latitude in Siberia and the Arctic Basin are the source regions. These areas recieve almost no solar radiation during the winter but continue to radiate thermal energy.

Front 8

What is the difference between maritime polar and continental polar air masses?

Back 8

Maritime polar form over the cold waters of the North Atlantic and North Pacific. They primarily affect the west coast of the united states. They occasionally bring heavy rains in winter.

Continental Polar- They form over the interior of Canada and Alaska. In winter, they can carry frigid air southward. In summer, cool, relatively dry, continental polar air masses bring relief from hot, humid weather.

Front 9

describe the Maritime tropical air masses

Back 9

the origins of the maritime tropical air masses are in tropical bodies of water. In summer, they bring hot, humid weather to the eastern two thirds of north america. The southwestern US and mexico are a source region of continental tropical air, which is hot and dry, especially in summer.

Front 10

Describe the Coriolis effect.

Back 10

The directions of Earth's winds are influenced by Earth's rotation. The Coriolis effect results in the fluids and objects moving in an apparent curved path rather than a straight line.

Front 11

In the coriolis effect, which direction does moving air move in the northern hemisphere? The southern?

Back 11

Northern: to the left
Southern: to the right
direction according to the "performer's" directions

Front 12

What are the polar easterlies?

Back 12

the polar easterlies are wind zones between 60 deg south lat and the north pole, and 60 deg south lat and the south pole

Front 13

What are the prevailing westerlies?

Back 13

The prevailing westerlies are the wind systems on Earth located between latitudes 30 deg north and 60 deg north and 30 deg south and 60 deg south. They are steady winds that move much of the weather across the united states and canada

Front 14

What are the trade winds?

Back 14

The trade winds are between latitudes 30 deg north and 30 deg south, are two circulation belts of wind. Air in these regions sinks, warms, and moves toward the equator in a westerly direction.

Front 15

What is a jet stream?

Back 15

A jet stream us a narrow band of fast wind, its speed varies with the temp differences between the air masses at the wind zone boundaries.

Front 16

What is a front?

Back 16

A front is a narrow region between two air masses of different densities.

Front 17

What is a thermometer?

Back 17

A thermometer measures temperature using either the Fahrenheit or Celcius scale.

Front 18

What is a barometer?

Back 18

A barometer measures air pressure

Front 19

What is an anemometer?

Back 19

An anemometer measures wind speed

Front 20

What is a hygrometer?

Back 20

A hygrometer measures humidity

Front 21

What is radiosonde?

Back 21

Radiosonde is an instrument used for gathering upper-atmospheric data at high altitudes, up to 30,000 meters

Front 22

what is the doppler effect?

Back 22

the doppler effect is the change in pitch or frequency that occurs due to the relative motion of a wave, such as sound or light, as it comes toward or goes away from the observer.

Front 23

What is infrared imagery?

Back 23

Infrared imagery detects the different frequencies, which enable meteorologists to map either cloud cover or surface temperatures. Different frequencies are detectable in an infrared image. It can be used to establish a storm's potential to produce severe weather.

Front 24

What is visible light imagery?

Back 24

Visible light imagery uses cameras that require visible light to photograph Earth. These digital photos are sent back to ground stations and their data are plotted on maps. Unlike weather radar, which tracks precipitation but not clouds, satellites track clouds but not necessarily precipitation.

Front 25

What is water vapor imagery?

Back 25

Water vapor imagery is another type of satellite imagery that is useful in weather analysis and forecasting . Water vapor absorbs and emits infrared radiation at certain wavelengths. it shows moisture in the atmosphere, not just cloud patterns. Meteorologists can closely monitor the development and change in storm systems even when clouds are not present.

Front 26

What is a station model?

Back 26

A station model is a record of weather data for a particular site at a particular time..

Front 27

What are isobars?

Back 27

Lines of equal pressure

Front 28

What are isotherms?

Back 28

Isotherms are lines of equal temperature.

Front 29

What is a digital forecast?

Back 29

A digital forecast is created by applying physical principles and mathematics to atmospheric variables and then making a prediction about how these variables will change over time.

Front 30

What is an analog forecast?

Back 30

An analog forecast is a type of forecast based on a comparison of current weather patterns to similar weather patterns from the past.

Front 31

What is a cold front?

Back 31

A cold front is when cold, dense air displaces warm air, it forces the warm air, which is less dense, up along a steep slope.
As the warm air rises, it cools and condenses. Intense precipitation and sometimes thunderstorms are common with cold fronts.

Front 32

What are isobars?

Back 32

Lines of equal pressure

Front 33

What are isotherms?

Back 33

Isotherms are lines of equal temperature.

Front 34

What is a digital forecast?

Back 34

A digital forecast is created by applying physical principles and mathematics to atmospheric variables and then making a prediction about how these variables will change over time.

Front 35

What is an analog forecast?

Back 35

An analog forecast is a type of forecast based on a comparison of current weather patterns to similar weather patterns from the past.

Front 36

What is a cold front?

Back 36

A cold front is when cold, dense air displaces warm air, it forces the warm air, which is less dense, up along a steep slope.
As the warm air rises, it cools and condenses. Intense precipitation and sometimes thunderstorms are common with cold fronts.

Front 37

What is a warm front?

Back 37

A warm front is advancing warm air that displaces cold air along a warm front. A warm front develops a gradual boundary slope.
a warm front can cause widespread light precipitation.

Front 38

What is a stationary front?

Back 38

A stationary front is when two air masses meet but neither advances, the boundary between them stalls. This front frequently occurs between two modified air masses that have small temperature and pressure gradients between them.

Front 39

What is a occluded front?

Back 39

When a cold air mass moves so rapidly that it overtakes a warm front and forces the warm air upward. As the warm air is lifted, the advancing cold air mass collides with the cold air mass in front of the warm front. Strong winds and heavy precipitation are common along an occluded front.

Front 40

Explain low-pressure systems

Back 40

In surface low-pressure systems, air rises. When air from outside the system replaces the rising air, this air spirals inward toward the center and then upward. Air in a low-pressure system in the northern hemisphere moves in a counterclockwise direction. The opposite occurs in the southern hemisphere for a low-pressure system. As air rises, it cools and condenses into clouds and precipitation. Therefore, a low-pressure system, whether in the northern hemisphere or southern, is often associated with cloudy weather and precipitation.

Front 41

Explain high-pressure systems.

Back 41

In a surface high-pressure system, sinking air moves away from the system's center when it reaches Earth's surface. The Coriolis effect causes the sinking air to move to the right, making the air circulate in a clockwise motion in the northern hemisphere and in a counter clockwise in the southern hemisphere. High pressure systems are usually associated with fair weather. They dominate most of Earth's subtropical oceans and provide generally pleasant weather.