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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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