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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. 7 th Grade
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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 • 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…
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 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: • 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: • Thousands of deaths • Billions of dollars lost around the world
Monsoons Location: • South Asia
Monsoons Source of wind: • 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 Impacton Humans (continued) • 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: • Rhone Valley, France
Mistral Source of Wind: • Cold, north-westerly wind that blows down the Rhone valley.
Mistral Incidence: • 100 days a year
Mistral Effect on environment: • Winds blow 40 to 80 mph • 100 days per year • Trees grown permanently bent
Mistral Impact on Humans: • Homes have windows only on the southeast side for protection from the cold, dry wind that blows through the Rhone Valley.
Sirocco Location: • Wind blows from North Africa to Italy.
Sirocco Source of wind: • 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 Incidence: • Spring and Summer
Sirocco Effect on environment: • Supports the Mediterranean Climate with sunny, mild summers. • Cool moist fall and winter replaces Sirocco.
Sirocco Impact on Humans: Italy • Encourages rain • Climate allows Italian farmers to grow crops
Sirocco Extension: • 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 • Soil erosion from overgrazing • Other poor farming practices; • Desertification; • Inadequate supplies of potable water
Harmattan Location: • South of Sahara • West coast of Africa • Algeria, Guinea, Guinea-Bissau
Harmattan Source of Wind: • 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: • 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: • Hot, dry, dusty Harmattan haze may reduce visibility during dry season • Inadequate supplies of potable water • Desertification