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How Blows the Wind?
Charlsie Allen, NBCT
OKAGE Teaching Consultant
Purpose



To locate and identify wind patterns of
the world;
to describe their effect on the
environment; and
To identify and describe how humans
have adapted life to these wind
patterns.
PASS
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


7th Grade
Standard 3.1 Recognize regional climatic
patterns … prevailing winds….
Standard 5.0 The student will examine the
interactions of humans and their
environment.
Standard 5.2 Evaluate the effects of human …
adaptation to the natural
environment…desertification….
A Legend…
The Ancient Greeks used
to think that wind was the
Earth breathing in and
out. We now know that it
is just…
air on the move.
Global Wind Patterns
Air moves between different
areas around the world.
 Air moves at different heights in
the atmosphere.

Global Wind Patterns


Colder air from the poles tends to
sink and move towards the equator
closer to the surface of the Earth.
Warm air from the equator rises
and moves towards the poles high
in the atmosphere because it is
lighter.
Coriolis Effect



Causes distinct pattern of winds
around the world.
In the northern hemisphere, winds
blow to the right.
In the southern hemisphere, winds
blow to the left.
Major Wind Patterns

Westerlies
Trade winds
Roaring Forties

The Doldrums


Wind Patterns
Wind patterns occur all over
the world and these
patterns have names
given by local residents.
Chinook Winds
Location:

North America
Chinook Winds
Source of wind:

Cold arctic winds from northern
Canada.
Chinook
Wind
Chinook Winds
Effects on environment

Colder than usual winters
throughout the United States
Chinook Winds
Impact on Humans:



Colder winters cause higher
heating bills.
Cattle are lost in harsh winters
Businesses lose money during bad
winters.
El Niño and La Niña
Location:

Pacific Ocean
El Niño and La Niña
Source of wind:


Winds blowing East to West across
the Pacific weaken and change
course.
The large warm air mass near
Australia begins to move east
toward South America.
El Niño and La Niña
La Niña
El Niño
El Niño and La Niña
Incidence:


In the past, every 4 to 5 years
Recently, more often
El Niño and La Niña
Effects on environment:

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Severe storms in North and South
America.
Drought in Australia
Polar jet stream moved north.
Eastern United States has warmer
winter.
El Niño and La Niña
Effects (continued)


The Pacific jet stream moves
further south than usual.
Fierce storms hit California’s coast
which usually has mild, sunny
weather.
El Niño and La Niña
Impact on Humans:
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Thousands of deaths
Billions of dollars lost around the
world
Monsoons
Location:

South Asia
Monsoons
Source of wind:
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
Summer – Wet Monsoons begin in
the Indian Ocean between India
and Africa.
Winds move northeast across India
toward the Himalayas.
Monsoons
Incidence:



Regularly each year
Summer Monsoon – May to
September
Winter Monsoon – October to April
Monsoons
Effects on environment:


Before the summer Monsoon rains,
land mass heats to 120° F.
Winter Monsoons bring cool land,
mild temperatures, low humidity.
Monsoons
Impact on Humans:


Monsoons are key to farming
success.
Seeds planted before Monsoon
develop roots before the rains
come.
Monsoons
Impact on Humans (continued)
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
If Monsoons are late, young plants
die, and famine follows.
If Monsoons are early or too
severe, young plants wash away,
and famine follows.
Mistral
Location:
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Rhone Valley, France
Mistral
Source of Wind:
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Cold, north-westerly wind that blows
down the Rhone valley.
Mistral
Incidence:

100 days a year
Mistral
Effect on environment:
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
Winds blow 40 to 80 mph
100 days per year
Trees grown permanently bent
Mistral
Impact on Humans:
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Homes have windows only on the
southeast side for protection from the
cold, dry wind that blows through the
Rhone Valley.
Sirocco
Location:
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Wind blows from North Africa to
Italy.
Sirocco
Source of wind:
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
Over north Africa, winds become hot
and dry and blow toward Italy
Sirocco is a hot, dust-and-sand-laden
wind especially common in summer
blowing from Algeria northward.
Sirocco
Wind
Sirocco Winds
Sirocco
Incidence:

Spring and Summer
Sirocco
Effect on environment:
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
Supports the Mediterranean
Climate with sunny, mild summers.
Cool moist fall and winter replaces
Sirocco.
Sirocco
Impact on Humans: Italy

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Encourages rain
Climate allows Italian farmers to
grow crops
Sirocco
Extension:
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
What might happen to farmers if
the Sirocco wind blew all year long?
How might the climate of Italy be
affected if there were no Sirocco
wind?
Sirocco
Impact on Humans: Algeria
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Soil erosion from overgrazing
Other poor farming practices;
Desertification;
Inadequate supplies of potable water
Harmattan
Location:
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South of Sahara
West coast of Africa
Algeria, Guinea, Guinea-Bissau
Harmattan
Source of Wind:
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Dry, dusty wind which blows south
from the Sahara in winter.
Brings dust storms and very dry air.
Harmattan
Incidence:

Blows in winter
Harmattan
Effect on environment:
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Generally hot and humid;
Monsoonal-type rainy season (June to
November) with southwesterly winds;
Dry season (December to May) with
northeasterly Harmattan winds
Harmattan
Impact on humans:
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Hot, dry, dusty Harmattan haze
may reduce visibility during dry
season
Inadequate supplies of potable
water
Desertification
Discussion Questions
Extension:
Is there a connection between the Sirocco
and the Harmattan?
 Both begin in the Sahara
 Sorocco blows north in summer
 Harmattan blows south in winter
Other Named Winds
The Levante:
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an easterly Mediterranean wind
bringing mild, moist air to Gibraltar
and the mainland of Spain and
Africa.
Other Named Winds
The Pampero:
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a very cold south westerly wind in
Argentina
formed in the middle of the continent
blowing across the Pampas grasslands.
Resources
http://www.rcn27.dial.pipex.com/cloudsrus/activities.html Games and activities on weather,
winds, and climate.
http://www.rcn27.dial.pipex.com/cloudsrus/wind.html Definitions of winds and wind patterns.
http://www.rcn27.dial.pipex.com/cloudsrus/features.html Weather and climate patterns.
http://www.cia.gov/cia/publications/factbook/geos/gv.html Facts and maps on most countries of
the world.