natural disasters

sandstorm

• Duststorms and sandstorms are strong winds blowing through the desert.
• Duststorms and sandstorms are caused by winds that carry sand and dust.
• In a sandstorm, you cannot see anything.
• The strong winds start when currents are created by  heating of the ground
• Swirling sand makes clouds 20 meters above the ground.

Tsunamis

• A tsunami is a series of waves that generate in an ocean 
• Caused by earthquakes, landslides, or volcanic eruptions under water.
• Earthquakes- when tectonic plates move under water. Causes water to move up
• and down. This creates a tsunami wave.

hurricanes

• Hurricanes occur in the warm ocean with a temperature of 29 degrees  
• or warmer.
• Warm ocean water gives a hurricane energy and causes evaporation
• making humid air rise, which create clouds of the storm.

Hurricane continued

• Then light winds outside the hurricane help it to grow.
• A hurricane can have strong winds that go as fast as 200 mph.

Floods

• Floods are the results of heavy rain.     
• Melting snow can also cause a flood.
• This causes rivers to rise causing floods.

TORNADOES

• A tornado is caused by a thunderstorm.
• Hot air and cold air  create instability.
• When the wind changes direction and speed, it causes 
• a rotating effect in the lower atmosphere.
• Rising air makes this effect vertical creating a tornado.

tornado

• For a tornado to occur:
• The air pressure has to be falling
• The wind has to be variable which is unsteady
• One air mass has to be cold and dry
• The other air mass has to be warm and moist

EARTHQUAKE

• Earthquakes are formed when tectonic plates 
• shift and rub against each other. This causes the ground to move.
• When they move, they put force on each other which breaks the earths crust.
• When the break happens,stress is released as energy which moves 
• through the earth as waves. We feel this and call it an earthquake.

Volcanos

• When the tectonic plates under the ground move,
• stones and lava will shoot up and make a volcanic eruption.

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