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and spread over Myanmar (Burma) near Yangon. It countries have sent aid to the affected people.
weakened on 3 May. India too sent two ships and two aeroplanes
carrying relief material.
This cyclone claimed
77,738 lives while
55,917 people were Activity
reported missing. On Collect information about any cyclone that has
an estimate, over occurred recently with photographs. Write a case
10,00,000 people were study on its cause, area and loss of life and
severely affected by property.
the cyclone. A house damaged in Yangon
The Nargis cyclone is said to be the deadliest Info Bits
Info Bits
cyclone since 1970, when in the Bhola cyclone
about 5,00,000 people lost their lives. The six main types of cyclones are–polar cyclones,
The actual figure of casualties in Myanmar is not polar lows, extratropical cyclones, subtropical
known. However, international agencies and other cyclones and mesocyclones.

v The atmosphere is an envelope of air around the earth. It is made up of various gases, water vapour, dust
and other particles.

v Troposphere, stratosphere, mesosphere, ionosphere and exosphere are the different layers of the
atmosphere.

v Weather is the condition of the temperature at a particular area over a short period of time.
v Climate is the average weather conditions of a large area over a long period of time.
v Water vapour in the atmosphere influences the weather and climate of any place.
v The element of weather and climate are temperature, pressure, wind, humidity, precipitation etc.
v The degree of hotness or coldness of the air is termed as temperature.
v Atmospheric pressure is the weight of the air pushing down on a unit area on the earth’s surface.

v The factors that control the temperature of a place are latitude, altitude, distance from sea, winds etc.
v Winds move from areas of high pressure to areas of low pressure.
v There are three types of winds—planetary, periodic and local.
v Based on the mechanism of their formation, rainfall can be classified into three types—convectional, relief
and cyclonic rainfall.
v Cyclones are violent storms associated with the high circulatory winds in the lower parts of the atmosphere.

A. Tick (3) the right option :
1. The percentage of ______________ in atmosphere is 78%.
(a) nitrogen (b) oxygen (c) argon

The Atmosphere
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