tropical cyclone 2015
TRANSCRIPT
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Tropical Cyclones.Tropical Cyclones are known by many
names:
• Typhoons in South-East Asia
• Hurricanes in the Caribbean.
• Tropical Cyclones in the South West Pacific
• These weather patterns are extremely dangerous to humans because in general we live on or near the coast.
• In the South-West Pacific tropical cyclones regularly devastate the social and economic basis of many countries. ie Queensland after Cyclone Yasi
• Most of the smaller Polynesian countries are at risk from Cyclones. Fiji Tonga or Vanuatu.
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• Category One: Winds 74-95 mph (119-153 kph). Storm surge generally 1-2m above normal. Little damage to buildings.
• Category Two: Winds 96-110 mph (154-177 kph). Storm surge generally 2-2.5m above normal. Some roofing, door, and window damage of buildings.
• Category Three: Winds 111-130 mph (178-209 kph). Storm surge generally 3-4m above normal. Some structural damage to small residences and outside buildings
• Category Four: Winds 131-155 mph (210-249 kph). Storm surge generally 4-6m above normal. External walls fail with some complete roof failures on small houses.
• Category Five: Winds greater than 155 mph (249 kph). Storm surge generally greater than 6m above normal. Complete roof failure on many residences and industrial buildings. Serious flooding.
Category 1 to 5 Cyclones
The Processes On the Earth: Simple
Southern Summer:Cyclone Season is December to May
The ITCZ, the wide strip of Calm weather created by rising warm air moves with the sun as far as 15° South (The South Pole is 90° South).Why were they called the ‘Horse Latitudes’.
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• The warm settled conditions create large amounts of evaporation which rise to become clouds.
• As the warm moist air rises it creates an area of low air pressure beneath it
• This why it is called a Low. (pressure area)• As the warm wet air rises into the atmosphere
cooler air moves in to replace it - it creates wind.• As this wind moves toward the centre of the
Low, the Earth's rotation causes it to spiral (SPIN) in towards the Centre.
• This spiral effect is called the Coriolis Affect.• The closer the wind gets to the Low the faster it
moves.• As the moist air reaches the centre and rises it
condenses (cools) releasing large amounts of (LATENT) heat energy which helps to strengthen the Cyclone.
Processes above the Earth
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The Storm Surge and its effects on a Low Island
Low
The surge can raise the sea level by several metres. Most Low islands are only a few metres above high tide. Even if the surge is not as high as the island, high waves – often over 5 metres can still cover the island. As well as the flood and wind damage the sea can also poison valued fresh ground water supplies.
The Low Pressure allows the sea to rise and appears as a large hump many kilometres across.
A Category 5 Cyclone can raise
the sea level by 6m
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Tropical Cyclone Prezi• Construct a Prezi describing the processes which
produce a Tropical Cyclone /Hurricane.
Describe the processes which produce your chosen Hazard.
Time of the YearDec- May Zoe and Ami
Sea Temperature26.0° CCreates evaporation
ITCZMoves South followingThe Sun (Season)Creates warm calm conditions
Low pressureWind Coriolis Effect
Wind Further EvaporationLatent heat Low to Cyclone
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5
3
2
4
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Damage caused by Tropical Cyclones.
• The high winds generated within a cyclone can create havoc, causing large amounts of damage to structures such as buildings as well as crops.
• The heavy rainfall associated with a cyclone can cause problems through flooding damaging buildings, roads, bridges, drainage systems and crops.
• The high winds and the heavy rainfall can endanger peoples lives, mainly through drowning, or through injury.
• Storm Surges can destroy structures and drown people.
• Extensive damage can be caused to peoples property and to Public utilities and services.