What are Natural Disasters? : What are Natural Disasters? Slide 2: The World is always changing.
Natural disasters are changes which are so great they may cause damage to the shape of the land or to the lives of people and other living things.
Great changes happen deep inside the Earth and on its surface. The changes on the outer part of the Earth happen because of different kinds of weather. What are Natural Disasters? : What are Natural Disasters? Volcanic eruption
Cyclone or Hurricane
Forest fire or Bushfire Volcanoes : Volcanoes A volcanic eruption is the spurting out of gases and hot lava from an opening in the Earth’s crust.
Pressure from deep inside the Earth forces ash, gas and molten rock to the surface. Earthquake : Earthquake An earthquake is a violent shaking of the ground. Sometimes it is so strong that the ground splits apart.
When parts of the earth, called plates, move against each other giant shock waves move upwards towards the surface causing the earthquake. Cyclone, Hurricane, Tornado or Typhoon : Cyclone, Hurricane, Tornado or Typhoon A Cyclone is a fierce storm with storm winds that spin around it in a giant circle. During a cyclone trees can be uprooted, buildings can be destroyed and cars can be overturned. Avalanche : Avalanche An Avalanche is a movement of snow, ice and rock down a mountainside. Avalanches happen very suddenly and can move as fast as a racing car up to 124mph.
Avalanches can be caused by –
snow melting quickly
snow freezing, melting then freezing again
a loud noise or an earth tremor Flood : Flood A flood is caused by an overflow of water which covers the land that is usually dry.
Floods are caused by heavy rain or by snow melting and the rivers burst their banks and overflow.
Costal floods are caused by high tides, a rise in sea level, storm waves or tsunami (earthquakes under the sea). Drought : Drought A drought is the lack of rain for a long time.
In 1968 a drought began in Africa. Children born during this year were five years old before rain fell again. Forest Fire or Bushfire : Forest Fire or Bushfire Fires can burn out of control in areas of forest or bush land. Fires are caused by lightning, sparks of electricity or careless people. Wind may blow a bushfire to areas where people live.