GeographicGeographical al

Influences Influences on Weatheron Weather

EQ: How do EQ: How do mountains, large mountains, large

bodies of water and bodies of water and wind affect climate wind affect climate

and weather?and weather?

MountainsMountains Temperature of mountainous areas Temperature of mountainous areas Rain shadow effect (video 1:15)Rain shadow effect (video 1:15) http://www.teachertube.com/viewVideo.php?video_id=20

0048

Bodies of WaterBodies of Water Water temperatures change more slowly Water temperatures change more slowly

than land temperatures.than land temperatures. This means areas near large bodies of This means areas near large bodies of

water will have milder temperatures since water will have milder temperatures since the water helps regulate the land the water helps regulate the land temperatures.temperatures.

Land near large bodies of water will also Land near large bodies of water will also get more snowfall because of the moisture get more snowfall because of the moisture in the air (from the nearby water)in the air (from the nearby water)

Breezes and WindsBreezes and Winds Breezes and winds are also affected by Breezes and winds are also affected by

temperature and bodies of water.temperature and bodies of water. Some different types of breezes are:Some different types of breezes are:

seasea land land mountainmountainvalleyvalley

Sea BreezeSea Breeze Along the coast, land and sea are heating Along the coast, land and sea are heating

differently. This leads to the development differently. This leads to the development of local winds called sea breezes.of local winds called sea breezes.

As air above the land surface is heated by As air above the land surface is heated by radiation from the Sun, it expands and radiation from the Sun, it expands and begins to rise, being lighter than the begins to rise, being lighter than the surrounding air.surrounding air.

To replace the rising air, cooler air is To replace the rising air, cooler air is drawn in from above the surface of the drawn in from above the surface of the sea. This is how a sea breeze is formed.sea. This is how a sea breeze is formed.

A land breeze occurs at night when the land A land breeze occurs at night when the land cools faster than the sea. cools faster than the sea.

The air above the water is warmer than the The air above the water is warmer than the land so it rises, creating a low pressure area.land so it rises, creating a low pressure area.

The air above the land is cooler (a high The air above the land is cooler (a high pressure area) so it flows towards the water, pressure area) so it flows towards the water, into the low pressure area, creating a land into the low pressure area, creating a land breeze.breeze.

Land BreezeLand Breeze

Land BreezeLand Breeze

During the day, the surface of the mountain During the day, the surface of the mountain heats the air high up in the atmosphere, heats the air high up in the atmosphere, quicker than the valley floor can. quicker than the valley floor can.

As the warmer air expands a low pressure area As the warmer air expands a low pressure area is created near the top of the mountain. The is created near the top of the mountain. The valley is a high pressure area, so, that air flows valley is a high pressure area, so, that air flows toward the low pressure area, creating a toward the low pressure area, creating a breeze that blows from the valley floor up breeze that blows from the valley floor up towards the top of the mountain. towards the top of the mountain.

Valley BreezeValley Breeze

In the evening, the mountain slopes In the evening, the mountain slopes cool the surrounding air more quickly cool the surrounding air more quickly than the air found lower in the than the air found lower in the atmosphere like in the valley. atmosphere like in the valley.

The high pressure area of the cooler The high pressure area of the cooler mountain tops blows down the mountain tops blows down the mountain towards the low pressure mountain towards the low pressure area of the warmer valley. area of the warmer valley.

Mountain BreezeMountain Breeze

Valley and Mountain BreezesValley and Mountain BreezesWhen 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 ThinkRead and Think Read with a partner about Read with a partner about

the geographical the geographical influences on weather influences on weather and climate (pages 113-and climate (pages 113-115 in the EOG Science 115 in the EOG Science BookBook

Discuss with your partnerDiscuss with your partner On your own, answer On your own, answer

questions 1-4 on page questions 1-4 on page 116.116.

sourcessources

http://www.kidsgeo.com/geography-for-kids/0084-pressure-and-density.php

http://www.britannica.com