This document discusses atmospheric pressure and instruments used to measure it. It describes how cyclones form as centers of low pressure and anticyclones as centers of high pressure. It also discusses volcanoes, explaining their formation from gases pushing melted rocks up through the earth's crust and mantle. The conclusion states that while preventing cyclones and volcanoes is impossible, an efficient warning system can help mitigate disasters.

1. Kalyan Kumar

2.  Atmospheric pressure
 Cyclones
 Anticyclones
 Instruments for measuring
 Volcanoes
 Conclusion
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3.  Force exerted by the weight of the air above
 Weight of the air at sea level
 14.7 pounds per square inch
 1 kilogram per square centimeter
 Units of measurement
 Millibar (mb) – standard sea level pressure is 1013.2 mb
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4. A center of low pressure
Pressure decreases toward the center
Winds associated with a cyclone
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5. A center of high pressure
Pressure increases toward the center
Winds associated with a cyclone
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7. Barograph
Barometer
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8.  The outer crust is made of rocks
 Underneath the crust is the mantle
 The gases push these melted rocks called ‘magma’
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9.  A Volcano is a special kind of mountain that builds itself
 There are several thousand volcanoes in the world
 Most of them are extinct
 Some are dormant
Arenal, Near Panama, Central America
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10. Prevention of formation of cyclones or volcanoes are not in
the realm of possibility. One of the mitigation measure
against disaster is the efficient warning system.
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