The Natural Disasters in Australia and Their Effects
Earthquakes are caused by the shifting of the Indian-Australian plate,
which is being pushed north and is colliding with the Eurasian,
Philippine and Pacific plates. The stress from this collision is
released during earthquakes. Earthquakes can occur anywhere in
Australia. Adelaide has the highest earthquake hazard of any capital
city, with more earthquakes in the past 50 years than any other.
Thunderstorms however are more common on the east coast of Australia.
Thunderstorms develop when dense cold air meets warm, moist air, which
is less dense. A trigger, such as solar heating can then begin the
development of a thunderstorm. Strong upward currents of air develop.
As the air is carried upwards quickly water droplets in the air
condense to form rain. These raindrops can turn into hail.
When these rain drops reach high levels they freeze, forming hail
stones. These hail stones then grow steadily in size as they are
carried up and down by strong currents of air. Hail stones larger than
tennis balls have been recorded in Australia. Hail can also occur when
a cyclone forms.
Cyclones are formed near the equator. The sun heats the sea, and some
water evaporates. Clouds build up, and a low pressure system starts
these clouds rotating. As the clouds build up speed they form a
cyclone. Cyclones occur most frequently off the northwest coast of
Western Australia, in the Gulf of Carpentaria and in the Coral Sea.
Cyclones are often confused for tornadoes, which are formed in a
Tornadoes form during thunderstorms when hot air meets cold air large
amounts of wind can be produced by the warming and cooling of the air.
A tornado can range in width from a few metres to several hundred
metres in width. Tornadoes spin clockwise and contain winds that may
reach more than 300 km/h. Thunderstorms can also cause flash flooding.
Flash flooding occurs...