Name:_____________________________ Period:_____
19.1 Air Pressure
What is Air Pressure?
A) Differences in air pressure cause __________ and
____________ differences
B) Air Pressure- _________ of the atmosphere per unit area
1) 1 kg/ cm @ surface
C) Air pressure is __________ directed in all ___________
1) horizontally and vertically
Measuring Air Pressure
A)
- device used to measure air pressure
1)
- mercury rises or falls in a tube due to increased
or decreased air pressure
2)
- thin can collapses or expands due to
increased or decreased air pressure
3) Air pressure decreases with ____________
Recording Air Pressure
A) Air pressure is measured in __________ or _____ using a
barometer
B)
- 1/1000 of standard sea level A.P.
1) _________________ = standard sea level
Why Does Air Pressure Change?
A) Air pressure changes due to __________ and __________
1) ___________ temp. = _________ air pressure
a) molecules further apart
B) Increased __________ (high humidity) = _______ air pressure
1) water vapor is lighter than 02 and N2, thus lower air pressure
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C) Falling barometer, decreased A.P., indicates approaching
________ (rain or snow)
D) Isobars- lines connecting points with equal ________ on a
weather map
E) High Pressure Area- area where pressure is _________ than
surrounding air
1) isobars form closed ______ with smaller rings representing
higher A.P.
F) Low Pressure Area- area where pressure is _______ than
surrounding air
1) isobars form closed rings with smaller rings representing
________ air pressure
G) Pressure Gradient- rate of change of ___________
1) __________- lines close together (rapid change)
2) __________- lines spaced apart (slow change)
19.2 Factors Affecting Winds
What Make the Wind Blow?
A) Air moves from areas of ____ pressure to areas of
_______ pressure
1) the ______ the pressure _______, the _________ the winds
B) ________ differences are the result of unequal _______ of the
Earth’s __________
1) cold- ______ pressure
2) warm- ______ pressure
Measuring Wind Direction and Speed
A) Anemometer- measures wind ________
B) Wind Vane – measures wind _________
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The Coriolis Effect
A) Coriolis Effect- tendency for an object _______ freely over the
Earth’s ______ to _____ away for its ____ of travel
1) due to Earth’s _________
2) objects in NH deflected _______
3) objects in SH defected ________
4) greater at ________ than at _________
5) more noticeable with _________ speed
The Coriolis Effect Continued
6) Makes winds spin ____________ around _____ and
_______ around ______ in NH
Friction
A) ________ between air and ground ______ Coriolis Effect at
surface on winds
1) ______ surfaces deflect winds ____ degrees to isobars
2) ______ surfaces cause winds to be deflected nearly
________ to isobars
3) ______ deflects wind ___ degrees to isobars
4) _______ altitude _______ friction
a) winds nearly ________ to ______
B) Jet Stream- a _______ altitude air current forms a narrow band
of very strong ________ winds flowing above ___________
1) travels at _____ km/hr
2) occurs _____ km above surface
3) affects weather in _____
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19.1 Air Pressure and Wind
Directions: Use pages 414-418 of your text to answer the following questions.
Ch 19-1
1. What causes the movement of air? _________________________________________
2. Define air pressure. ___________________________________________________
___________________________________________________________________
3. Why is the air at ground level so heavy? _____________________________________
___________________________________________________________________
4. How does air pressure change with a change in elevation? _________________________
___________________________________________________________________
5. Compare and contrast mercury and aneroid barometers.__________________________
___________________________________________________________________
____________________________________________________
6. Air pressure is measured in a variety of units. List and describe the units below:
___________________________________________________________________
___________________________________________________________________
7. How and why do meteorologists use air pressure from weather stations across the country?
___________________________________________________________________
___________________________________________________________________
Why Does Air Pressure Change?
8. How does temperature affect air pressure? ___________________________________
___________________________________________________________________
9. What happens when warm air replaces cool air in a region? ________________________
___________________________________________________________________
10. What is the relationship between change in humidity and air pressure? _______________
_____________________________________________________________________
_____________________________________________________________________
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11. How do weather forecasters use changes in air pressure? _________________________
___________________________________________________________________
12. Describe an isobar. How does it compare with an isotherm? _______________________
___________________________________________________________________
13. When using isobars, how do you know you have a high pressure area?
___________________________________________________________________
___________________________________________________________________
14. What is a pressure gradient? ____________________________________________
___________________________________________________________________
___________________________________________________________________
Directions: Use pages 414-418 of your text to answer the following questions.
19-1 Continued
What Makes the Wind Blow?
1. In what direction does air move? _____________________________________________
_____________________________________________________________________
2. How do differences in air pressure affect wind strength? ____________________________
_____________________________________________________________________
_____________________________________________________________________
3. What causes pressure differences? ___________________________________________
_____________________________________________________________________
4. Describe the formation of a sea breeze._________________________________________
_____________________________________________________________________
_____________________________________________________________________
5. Refer to the diagram at the top of page 417 to answer the following questions:
A. What part of the world is shown on the weather map? ___________
B. What is the name of the looping line on the map? ______________
C. What happens to the lines that run off the map? _______________
__________________________________________________
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D. Where on the map would you expect to find the strongest winds? ________
_______________________________________________________
E. Where on the map would you find the weakest winds? ________________
F. Why? _________________________________________________
_______________________________________________________
6. Describe how a wind vane shows wind direction. ____________________
_______________________________________________________
7. What is an anemometer? ____________________________________
_______________________________________________________
8. What other informal methods are used for estimating wind speed? _______
________________________________________________________
Directions: Use pages 419-421 of your text to answer the following questions.
Chapter 19-2
1. What is the general direction of wind?______________________________________
2. Define the Coriolis effect ________________________________________________
_________________________________________________________________
3. What causes the Coriolis effect? __________________________________________
_________________________________________________________________
4. Where is the Coriolis effect most significant?
* the equator or the poles
* fast or slow objects
* long or short distances
5. How does the Coriolis effect influence the winds in the Northern Hemisphere?
_________________________________________________________________
_________________________________________________________________
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6. What is the overall direction of wind around an area of high pressure? ____________
Low pressure?_________________________________________________________
7. How does friction influence surface winds?___________________________________
_________________________________________________________________
8. Why does friction reduce the impact of the Coriolis effect? ______________________
__________________________________________________________________
9. How does the topography of the land influence the Coriolis effect?________________
_________________________________________________________________
10. The angle of wind to the isobar over land is 30° and the angle of wind to the isobar
over water is 10 °. What accounts for the difference?
_________________________________________________________________
_________________________________________________________________
11. What causes upper level winds to flow parallel to the isobars?
_________________________________________________________________
_________________________________________________________________
12. What causes a jet stream?
_________________________________________________________________
_________________________________________________________________
13. Where do jet streams occur?
_________________________________________________________________
_________________________________________________________________
14. What determines the speed of a jet stream?
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19.3 Global Wind Patterns
Directions: Use pages 422-425 of your text to answer the following questions.
1) What are the factors that affect global wind patterns? _____________________
_______________________________________________________________
_______________________________________________________________
2) Describe how winds would circulate on the planet if the Earth did NOT rotate.
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
3) How does the Coriolis Effect shift winds in the Northern Hemisphere?
_______________________________________________________________
4) How does the Coriolis Effect shift winds in the Southern Hemisphere?
_______________________________________________________________
Three- Celled Circulation Model
1) Identify the location of the three circulation cells in the Northern and Southern
Hemispheres.________________________________________________________
___________________________________________________________________
___________________________________________________________________
2) What is the cause of the three circulation cells? __________________________
___________________________________________________________________
Three- Celled Circulation Model (Continued)
3) What is the polar front? _____________________________________________
___________________________________________________________________
4) Describe the winds that blow in the circulation cell between 60 N and 90 N
latitudes. ___________________________________________________________
___________________________________________________________________
___________________________________________________________________
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5) Describe the winds that blow in the circulation cell between 60 N and 30 N
latitudes. __________________________________________________________
__________________________________________________________________
6) Describe the winds that blow between 30 N Latitude and the equator.
__________________________________________________________________
__________________________________________________________________
7) What happens in the same circulation belts in the Southern Hemisphere? Why?
__________________________________________________________________
__________________________________________________________________
Weaknesses of the Three-Celled Model
1) What are the middle latitudes? _______________________________________
___________________________________________________________________
2) Explain three weaknesses with the three-celled model of circulation.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
Strengths of the Three-Celled Model
1) Explain why the three- celled model a valid argument. ____________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
Description of Wind and Pressure Belts
1) What is the ITCZ? _________________________________________________
___________________________________________________________________
___________________________________________________________________
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2) What are the doldrums? _____________________________________________
___________________________________________________________________
3) What are the sub-tropical highs? ______________________________________
___________________________________________________________________
4) What are the horse latitudes? _________________________________________
___________________________________________________________________
___________________________________________________________________
5) Describe the trade winds. ___________________________________________
___________________________________________________________________
___________________________________________________________________
6) What are the prevailing winds? _______________________________________
___________________________________________________________________
___________________________________________________________________
19.4 Continental and Local Winds
Directions: Use pages 427- 429 of your text to answer the
following questions.
Continental and Local Winds
1) What is the cause of seasons? _______________________________________
__________________________________________________________________
2) What causes the global winds to shift over the course of the year?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
3) Why are the highest temperatures of the year not always associated with the
equatorial region? ____________________________________________________
___________________________________________________________________
___________________________________________________________________
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Effects of Seasons and Continents
1) Explain the pressure trend associated with continents and oceans in the summer
and how this affects winds. ____________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
2) Explain the pressure trend associated with continents and oceans in the winter
and how this affects winds. _____________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
_______________
Effects of Seasons and Continents (Continued)
3) What is a monsoon? _______________________________________________
__________________________________________________________________
4) What type of weather is associated with a monsoon in the summer? Why?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
5) What type of weather is associated with a monsoon in the winter?
Why_______________________________________________________________
___________________________________________________________________
___________________________________________________________________
6) Explain how and why the ITCZ moves over the course of the year.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
Local Winds
1) What is a local wind? ______________________________________________
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2) Use the diagram to explain the sea breeze and land breeze.
3) Explain the mountain breeze. ________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
4) Explain the valley breeze. ___________________________________________
___________________________________________________________________
___________________________________________________________________
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Chapter 19 Learning Objectives
19.1
 I can define air pressure.
 I can describe how changes in elevation affect air pressure.
 I can describe how changes in temperature affect air pressure.
 I can describe how changes in humidity affect air pressure.
 I can explain what makes the wind blow.
19.2
 I can describe the Coriolis effect.
 I can explain how the Coriolis effect affects wind direction.
 I can explain how friction affects wind direction.
 I can explain how pressure gradients affect wind direction.
19.3
 I can identify factors that affect global warming.
 I can describe the strengths of the three-celled circulation model.
 I can describe the weaknesses of the three-celled circulation model.
 I can use the three-celled circulation model to explain prevailing
winds and pressure regions.
19.4
 I can describe the effects of seasons on wind patterns.
 I can describe the effects of continents on wind patterns.
 I can explain the circulation of sea breezes.
 I can explain the circulation of land breezes.
 I can explain the circulation of mountain breezes.
 I can explain the circulation of valley breezes.
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Chapter 19 Study Guide
Topics covered on the test:
Make sure you can check off all of the learning objectives!
1. The relationship between humidity and air pressure.
2. Why aren’t we crushed by air pressure?
3. How is air pressure exerted?
4. Instruments that measure air pressure, wind speed and
direction.
5. The Coriolis effect and the things that influence it.
6. Wind – direction, deflection due to Coriolis
7. Differences in wind in Northern and Southern hemisphere
with wind and the Coriolis effect
8. Global pressure belts and wind belts – where they are,
direction of movement, what they are called
9. Formation of local winds-land, sea, mountain, valley and
monsoons
10. Isobars
11. Pressure gradients
12. Jet Stream
13. Monsoons
14. ITCZ location and variations
15. Coriolis effect and topography
16. Air pressure and humidity, temp, and elevation
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