Page 126 - SST Class 07
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There are a large number of seaports along its
                                                                          Info Bits
            coastlines. The Atlantic Ocean comprises of a                 Info Bits
            number of seas such as the Gulf of Mexico      , the
            Caribbean Sea  , the Mediterranean Sea  , the North      In   2000,    the    International   Hydrographic
            Sea  and the Baltic Sea . Its average depth is about     Organisation again included the Southern Ocean as
            3,736 m with the deepest point at Puerto Rico            its own ocean.
            Trench  measuring 9,460 m deep.
                                                                     Other Water Bodies
             Indian Ocean
                                                                    In addition to the oceans, there are a number of
            The Indian Ocean lies to the south of India and         seas , bays  and gulfs . These bodies have saline
            has been named after our country. It covers nearly      water. The seas are also vast bodies of seawater,
            20 percent of the total sea area. It is bounded by      but they are smaller in size, and form a part of the
            Africa on the west, Asia on the north, Australia on     oceans. A gulf    is an inlet of seawater which
            the east and Antarctica on the south. Its average       reaches deep into land. A bay        is an inlet of
            depth is about 4,900 m with the deepest point at        seawater with an opening, wider than a gulf.
            Java Trench which is about 7,542 m         deep. It     The freshwater sources are rivers, lakes, streams
            comprises a number of seas, such as the Red Sea    ,    and groundwater.
            the Arabian Sea   , the Bay of Bengal      and the
            Andaman Sea   .                                               OCEAN WATERS AND THEIR CIRCULATION

             Arctic Ocean                                           It is so enchanting when you walk on the
                                                                    seashore. The waves keep rising, the air keeps
            The Arctic Ocean lies to the north of Asia, Europe
                                                                    blowing, and there is before your eyes infinite
            and North America within the Arctic Circle. It
                                                                    mass of water appearing to rise in the distant
            remains frozen throughout the year. It is the
                                                                    horizon. The sea is never static. It keeps moving,
            smallest ocean. It is less saline due to a number of
                                                                    rising and falling. A number of factors contribute
            rivers flowing into it.
                                                                    in the movement of ocean waters—difference in
                                                                    temperature and salinity between different places,
                Quiz Time                                           and winds. The movement of ocean waters can be
                                                                    broadly classified as waves , tides  and currents .
            Fill in the blanks :
                                                                     Waves
            1. ___________    and ___________   are the largest
               water bodies.                                        The ocean is an open area covered with water,
            2. The ___________    is the deepest of all oceans.     where the wind moves without any hindrance.
                                                                    The wind moves along the water and pushes it in
            3. Indian Ocean covers only ___________      of the     the direction to which it is blowing. It results in
               total sea area.
                                                                    the rising and falling of water. You may be
            4. ___________    is the smallest ocean.                surprised to note that water particles do not move
                                                                    with the wind; they only rise and fall; it is only the
             Southern Ocean                                         wave movement which is transported. Just put a
                                                                    piece of wood; you will find that it goes up and
            It is the fourth largest of the world’s five oceans.
                                                                    down with the wave
            The Pacific, Atlantic and Indian Ocean merge at a
                                                                    movement,       but     it
            place and are collectively known as the Antarctic       remains where you put
            or Southern Ocean. It surrounds the landmass of
                                                                    it, it does not move
            Antarctica and remains frozen throughout the
                                                                    forward.   The   rise  of
            year. Its deepest point is South Sandwich Trench        waves is called crest  and
            at 7,235 m.
                                                                    the fall is called trough .
                                                                                                      Ocean waves
                     Contemporary Social Science-7
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