Winter and Summer Anticyclones

Mr. T. Tonna

Index

• What causes an Anticyclone?• Your Opinion• Summer vs Winter• What is the Difference?• Quiz Time• Summary• Homework

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Anticyclones

• Anticyclones are formed from an area of high pressure.

• They tend to bring clear, settled weather.• In an anticyclone, air descends and pressure

increases. This brings very light winds (which blow outwards from the centre in a clockwise motion), clear skies and dry conditions (because the air is descending and warming up, there are no clouds and no rain).

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• They are large masses of air circulating in a clockwise motion in the Northern Hemisphere and Anti-clockwise in the Southern Hemisphere.

• They form because the air within a certain area cools quicker than its surrounding environment causing itto descend.

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An Anticyclone Near Tasmania

Do You think the weather in depressions will change in winter in comparison to summer?

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Anticyclonic Weather Conditions:Winter Anticyclones Summer AnticyclonesDry and bright with very little cloud.

Very little cloud

Sun low in the sky, so cold conditions.

Dry with light winds

Clear evening skies mean that nights can be very cold.

Sun high in the sky, so hot and sunny

Early morning frost and fog may last all day.

Cloudless skies at night allow heat to escape, so nights can be cool.

Extensive low cloud or fog may produce overcast or ‘gloomy’ conditions.

Risk of thunderstorms at end of ‘heat wave’ conditions

Early morning dew and mist.

Quiz

• This is a class quiz so everyone will get the opportunity to give their opinion and explain their decisions.

• The quiz will be based on the past two lessons.• All questions will be open for discussion and

analysis.

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What is the difference between a Cyclone and an

Anticyclone?

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Which front is associated with the ‘wettest’ weather?

On the Following Map, what do the lines represent?

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Clear skies and high pressure are associated with what

Weather system?

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The Following photograph of an area experiencing an Anticyclone was taken in which season ?

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ANALYSE THE PICTURE PROPERLY!!

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Despite the fact that Anticyclones are usually associated with clear skies, Thunderstorms are common in which season?

Summary

• Anticyclones form as a result of a high pressure air mass sinking as a result of a fast warming process.

• Winter and Summer cyclones have similar conditions such as the clear skies both during the day and at night.

• In the summer the heating air can cause thunderstorms to occur.

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Homework

‘Weather conditions in Anticyclones are different in Winter and Summer’ Discuss

using examples. (150-300 words).

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