Chapter 18

Question 1

What is the lowest atmospheric pressure ever recorded?

Answer 1

870 Millibars (25.7 in.) during a Typhoon Tip

Question 2

What is standard sea level pressure in millibars? In inches of mercury? In pounds per square inch?

Answer 2

1013. 2 Millibars
1014. 92 in.
1015. 69 Pounds per square in.

Question 3

What force is responsible for generating wind?

Answer 3

Horizontal movement of air. Air flowing from areas of higher pressure to areas of lower pressure

Question 4

How does a barometer work?

Answer 4

Uses a glass tube filled with mercury

Question 5

What is an aneroid barometer?

Answer 5

A borometer without liquid. Uses an expanding chamber

Question 6

What is a barograph?

Answer 6

A device that continuously records air pressure

Question 7

what are the controls of wind?

Answer 7

Pressure gradient force, Coriolis effect, friction

Question 8

What is an isobar?

Answer 8

a line of equal air pressure

Question 9

What is a pressure gradient?

Answer 9

Pressure change over distance

Question 10

What is the Coriolis effect?

Answer 10

Apparent deflection in the wind direction due to Earth’s rotation
Deflection is to the right in the Northern Hemisphere and to the left in the Southern Hemisphere

Question 11

What is friction?

Answer 11

Only important near the surface

Acts to slow the air’s movement

Question 12

What are the two kinds of upper air winds?

Answer 12

Geostrophic winds, the jet stream

Question 13

What are geostrophic winds?

Answer 13

Generally blow parallel to isobars

Question 14

What is the jet stream?

Answer 14

“River” of air
High altitude
High velocity (120–240) kilometers per hour

Question 15

Why doesn’t the Coriolis effect cause a baseball to be deflected when you are playing catch?

Answer 15

Over short distances, the effect is not noticeable

Question 16

How does the Coriolis effect modify air movement?

Answer 16

Turns the air to the right in northern hemisphere, and to the left in the southern hemisphere

Question 17

What is the highest wind speed ever recorded?

Answer 17

372 kph (231 mph)

Question 18

In what prevailing winds do we reside?

Answer 18

The westerlies

Question 19

What is a cyclone?

Answer 19

A center of low pressure
Pressure decreases toward the center
Associated with rising air
Often bring clouds and precipitation

Question 20

What are cyclone winds like in the N. and S. Hemispheres?

Answer 20

In the Northern Hemisphere 
Inward (convergence)
Counterclockwise
In the Southern Hemisphere 
Inward (convergence)
Clockwise

Question 21

What is an Anticyclone?

Answer 21

A center of high pressure

Pressure increases toward the center

Question 22

What are the winds like in an Anticyclone?

Answer 22

In the Northern Hemisphere 
Outward (divergence) 
Clockwise
In the Southern Hemisphere 
Outward (divergence) 
Counterclockwise 
Associated with subsiding air 
Usually bring “fair” weather

Question 23

What is the underlying cause of general atmospheric circulation?

Answer 23

Unequal surface heating

Question 24

What influence do continents have on general atmospheric circulation?

Answer 24

Seasonal temperature differences disrupt the
Global pressure patterns
Global wind patterns

Question 25

What is a monsoon?

Answer 25

``` Seasonal change in wind direction Occur over continents During warm months Air flows onto land Warm, moist air from the ocean Winter months Air flows off the land Dry, continental air ```

Question 26

What are local winds, and what are the types of them?

Answer 26

``` Produced from temperature differences Small-scale winds Types- Land and sea breezes Mountain and valley breezes Chinook and Santa Ana winds ```

Question 27

What are the two ways we measure wind?

Answer 27

Direction and speed

Question 28

How do we measure wing direction, and why is that important?

Answer 28

With a wind vane, and because winds are labeled by their origins

Question 29

How do we often measure wind speed?

Answer 29

With a cup anemometer

Question 30

Why are changes in wind direction important?

Answer 30

``` Associated with locations of: Cyclones Anticyclones Often bring changes in: Temperature Moisture conditions ```

Question 31

What is El Nino?

Answer 31

A countercurrent that flows southward along the coasts of Ecuador and Peru Warm Usually appears during the Christmas season Blocks upwelling of colder, nutrient-filled water, and anchovies starve from lack of food

Question 32

What is the Southern Oscillation?

Answer 32

When pressure changed between the eastern and western Pacific due to El Nino

Question 33

What is El Nina

Answer 33

Opposite of El Niño Triggered by colder-than-average surface temperatures in the eastern Pacific Typical La Niña winter Blows colder than normal air over the Pacific Northwest and northern Great Plains while warming much of the rest of the United States Greater precipitation is expected in the Northwest