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1. Natural Disasters
Natural disasters are events that result from the Earth's natural phenomena. It is categorized into many types based on its occurrence.
 
Earthquake:
 
The sudden shaking of the earth at a place for a short period is called an earthquake. The duration of the earthquake may be a few seconds to some minutes.
 
The point where an earthquake originates is called its ‘focus’. The vertical point at the surface from the focus is called the ‘epicenter’.
 
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Earthquake
 
Volcanoes:
 
Volcanoes are openings or vents where lava, small rocks, and steam erupt onto the earth’s surface. On land, volcanoes form when one tectonic plate moves under another.
 
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Volcanoes
 
Tsunami:
 
Tsunamis are waves generated by earthquakes, volcanic eruptions, and underwater landslides.
Tsunami is a Japanese term that means "harbor wave".
 
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Tsunami
 
Cyclones:
 
A low-pressure area that is encircled by high-pressure wind is called a cyclone. The warm moist air over the sea rises from the surface in an upward trend, resulting in the formation of the low-pressure zone over the surface.
 
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Cyclone
 
Floods:
 
An overflow of a large amount of water, beyond its normal limits, especially in rainfed areas is called a flood.
 
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Flood
 
Landslide:
 
The movement of a mass of rocks, debris, soil, etc., downslope is called a landslide. Landslides are a kind of "mass wasting," which means any down-slope movement of soil and rock under the direct influence of gravity.
 
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Landslide
 
Avalanche:
 
A large amount of ice, snow, and rock falling quickly down the side of a mountain is called an Avalanche. In mountainous areas, avalanches are the most destructive natural threat to life and property.
 
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Avalanche
 
Thunder and lightning:
 
Thunder is a series of sudden electrical discharges resulting from atmospheric conditions. This discharge results in sudden flashes of light and trembling sound waves which are commonly known as thunder and lightning.