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1
Q

What is the lowest atmospheric pressure ever recorded?

A

870 Millibars (25.7 in.) during a Typhoon Tip

2
Q

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

A
  1. 2 Millibars
  2. 92 in.
  3. 69 Pounds per square in.
3
Q

What force is responsible for generating wind?

A

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

4
Q

How does a barometer work?

A

Uses a glass tube filled with mercury

5
Q

What is an aneroid barometer?

A

A borometer without liquid. Uses an expanding chamber

6
Q

What is a barograph?

A

A device that continuously records air pressure

7
Q

what are the controls of wind?

A

Pressure gradient force, Coriolis effect, friction

8
Q

What is an isobar?

A

a line of equal air pressure

9
Q

What is a pressure gradient?

A

Pressure change over distance

10
Q

What is the Coriolis effect?

A

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

11
Q

What is friction?

A

Only important near the surface

Acts to slow the air’s movement

12
Q

What are the two kinds of upper air winds?

A

Geostrophic winds, the jet stream

13
Q

What are geostrophic winds?

A

Generally blow parallel to isobars

14
Q

What is the jet stream?

A

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

15
Q

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

A

Over short distances, the effect is not noticeable

16
Q

How does the Coriolis effect modify air movement?

A

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

17
Q

What is the highest wind speed ever recorded?

A

372 kph (231 mph)

18
Q

In what prevailing winds do we reside?

A

The westerlies

19
Q

What is a cyclone?

A

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

20
Q

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

A
In the Northern Hemisphere 
Inward (convergence)
Counterclockwise
In the Southern Hemisphere 
Inward (convergence)
Clockwise
21
Q

What is an Anticyclone?

A

A center of high pressure

Pressure increases toward the center

22
Q

What are the winds like in an Anticyclone?

A
In the Northern Hemisphere 
Outward (divergence) 
Clockwise
In the Southern Hemisphere 
Outward (divergence) 
Counterclockwise 
Associated with subsiding air 
Usually bring “fair” weather
23
Q

What is the underlying cause of general atmospheric circulation?

A

Unequal surface heating

24
Q

What influence do continents have on general atmospheric circulation?

A

Seasonal temperature differences disrupt the
Global pressure patterns
Global wind patterns

25
Q

What is a monsoon?

A
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
26
Q

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

A
Produced from temperature differences
Small-scale winds 
Types-
Land and sea breezes
Mountain and valley breezes
Chinook and Santa Ana winds
27
Q

What are the two ways we measure wind?

A

Direction and speed

28
Q

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

A

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

29
Q

How do we often measure wind speed?

A

With a cup anemometer

30
Q

Why are changes in wind direction important?

A
Associated with locations of:
Cyclones
Anticyclones
Often bring changes in:
Temperature 
Moisture conditions
31
Q

What is El Nino?

A

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

32
Q

What is the Southern Oscillation?

A

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

33
Q

What is El Nina

A

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