NATURAL DISASTERS

By Emily Lam

TsunamisTsunamis (say: soo-NAH-mees) are a series of waves that send

surges of water sometimes reaching 30.5 metres high. Some people think it’s so bad they call it the killer wave. ‘Tsu’ in Japanese means harbour and ‘nami’ means wave so if you put them together they make harbour wave. Tsunamis are caused by large undersea earthquakes either near or at the tectonic plate boundary. When the plate rises or falls suddenly, it takes water above it creating rolling waves that causes tsunamis. Sometimes they are also caused by landslides and volcanoes.

This animation shows you what our planet looked like millions of years ago and what it looks like

VolcanoesA volcano is a mountain with an opening at the top.

Just below the surface of the earth is a pool of molten rock. When the plates under the volcano moves it causes friction between the plate and the rock which makes the rock and gases shoot up forming lava. An erupting volcano can cause tsunamis, flash flood, earthquake, mudflows and rock falls.

Active volcanoes on Earth 1500Active volcanoes under sea 80Dormant volcanoes on Earth 9Dormant volcanoes in space 10 and more

Extinct volcanoes on Earth 5000

Hurricanes

Hurricanes are a storm made of strong winds. Each and every hurricane lasts up to a week moving 10-20 miles an hour over ocean. Hurricanes gather heat and energy through contact with warm water. But watch out the evaporation from the sea water increases their power. Hurricanes rotate in an anti-clockwise direction around an eye. The centre of the storm otherwise known as the eye

is the calmest part of the hurricane.

Drought

Drought is when it doesn’t rain for a long period like for one month or more. When it doesn’t rain, farmers can’t grow crops and the government will set up a water restriction.

EarthquakeEarthquakes are the shaking,

rolling or sudden shock of the earth’s surface. They are the Earth's natural means of releasing stress. More than a million earthquakes rattle the world each year. Earthquakes can be felt over large areas although they usually last less than one minute. Earthquakes cannot be predicted - although scientists are working on it!

Glossary

earthquake: A sudden and violent shaking of the ground

Surges : move in a waveDormant volcanoes - a volcano which is presently

inactive but could erupt again. Evaporation: a process in which something is changed

from a liquid to a vapour without its temperature reaching boiling point

Bibliography

http://environment.nationalgeographic.com/environment/natural-disasters/tsunami-profile/

2:51 12/07/11http://en.wikipedia.org/wiki/Tsunami 3:10

12/07/11 http://www.weatherwizkids.com/weather-volcano.htm

4:01 12/07/11

http://www.drought.unl.edu/kids/ 5:17 12/07/11