Transcript Geographical Influences on Weather

Geographical
Influences
on Weather
EQ: How do mountains,
large bodies of water
and wind affect climate
and weather?
Mountains
 Temperature of mountainous areas
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Rain shadow effect (video 1:15)
http://www.teachertube.com/viewVideo.php?video_id=20
0048
Bodies of Water
 Water
temperatures change more slowly
than land temperatures.
 This means areas near large bodies of
water will have milder temperatures since
the water helps regulate the land
temperatures.
 Land near large bodies of water will also
get more snowfall because of the moisture
in the air (from the nearby water)
Breezes and Winds
 Breezes
and winds are also affected by
temperature and bodies of water.
 Some different types of breezes are:
 sea
 land
 mountain
 valley
Sea Breeze
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Along the coast, land and sea are heating
differently. This leads to the development of
local winds called sea breezes.
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As air above the land surface is heated by
radiation from the Sun, it expands and begins
to rise, being lighter than the surrounding air.
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To replace the rising air, cooler air is drawn in
from above the surface of the sea. This is
how a sea breeze is formed.
Land Breeze
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A land breeze occurs at night when the land
cools faster than the sea.
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The air above the water is warmer than the
land so it rises, creating a low pressure area.
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The air above the land is cooler (a high
pressure area) so it flows towards the water,
into the low pressure area, creating a land
breeze.
Land Breeze
Valley Breeze
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During the day, the surface of the mountain
heats the air high up in the atmosphere,
quicker than the valley floor can.
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As the warmer air expands a low pressure
area is created near the top of the mountain.
The valley is a high pressure area, so, that air
flows toward the low pressure area, creating
a breeze that blows from the valley floor up
towards the top of the mountain.
Mountain Breeze
 In
the evening, the mountain slopes cool
the surrounding air more quickly than
the air found lower in the atmosphere
like in the valley.
 The high pressure area of the cooler
mountain tops blows down the mountain
towards the low pressure area of the
warmer valley.
Valley and Mountain Breezes
When the valley floor
warms during the day,
warm air rises up the
slopes of surrounding
mountains and hills to
create a valley
breeze.
At night, denser cool
air slides down the
slopes to settle in the
valley, producing a
mountain breeze.
Read and Think
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Read with a partner about
the geographical
influences on weather
and climate (pages 113115 in the EOG Science
Book
Discuss with your partner
On your own, answer
questions 1-4 on page
116.
sources
 http://www.kidsgeo.com/geography-for-
kids/0084-pressure-and-density.php
 http://www.britannica.com