Isolation
The amount of sunlights rays an area receives overspecified time
Why does isolation vary ?
- varies with latitude
- high latitude = spread thinly
- low latitude = more concentrated
What does isolation cause ?
- isolation heats up air and it rises
- it heads either north or south (depending on the global atmospheric circulation model)
- it then cools and sinks giving high pressure
When air is sinking it is….
High pressure
- normally deserts
When air is rising it is….
Low pressure
- normally lush vegetated areas
Why does wind occur?
Wind occurs because air molecules move from areas of high pressure to areas of low pressure
The three names for tropical storms
- hurricane
- cyclones
- typhoons
Conditions needed for a Tropical storm
- Low pressure
- 27* so air can rise and create low pressure
- Over the ocean for moisture to form clouds
- Low wind sheer so clouds can rise without being torn apart
Distribution of tropical storms
- just above and below the equator normally 30* as they have perfect conditions
- do not form on the equator as the Corilois effect isn’t strong enough
Formation of a tropical storm
- the sun warm the ocean to 27*
- water evaporates and rises causing low pressure
- the warm air comes into contact with a mass of cold air forming clouds
- A column of the high-pressure develops at the centre. Winds form around the column
- Some cooled air sinks back down helping to create the eye
- air rushes in from high-pressure areas outside of the storm to lower pressure areas at the centre of the storm creating winds
- The whole storm rotates due to the Coriolis effect
What is the coriolis effect?
• the rotation of the earth causes winds to take a curved path
How does climate change effect the intensity of a tropical storm?
- tropical storms expected to become 2 to 11 % more intense by 2100
- The number of category 4 to 5 tropical storms has increased since the 1970s
- every degree increase in seasurface temperature will mean 3 to 5 percent increase in wind speeds
How will climate change will affect frequency and distribution of tropical storms?
- frequency is predicted to stay the same however the number of more severe storms is to increase
- The regions that experience tropical storms are not meant to change
What are the primary effects of a tropical storm?
- heavy rainfall
- wind speed at least 119km/h
- destroying houses, crops and infrastructure
What are the secondary effects of a tropical storm?
- heavy rainfall causes flooding and storm surges
- storm surges can get up to 5m in height
- heavy rainfall can be 500 mm in 24 hours
- landslides can occur due to heavy rainfall
- aid cannot be reached as roads are flooded
- water supplies can be contaminated with sea water or sewage which increases the risk of disease
What are the immediate responses to tropical storms?
- warning systems are broadcast to the public to allow them to prepare and protect themselves from the oncoming storm
- evacuation occurs
- distribution of emergency food and water
What are the long-term responses to a tropical storm?
- governments build more stable and tropical storm resistant buildings
- projects invest in better protection and protection equipment eg. Warning systems for storm surges
Key facts about typhoon Haiyan
- it was one of the strongest tropical storms ever recorded
- it hit South East Asia on the 8th of November 2013
- Windspeeds reached up to 200 mph
- The death toll was 6340
- 27,000 people were injured
- 670,000 people were left homeless
- category 5 storm
Path of typhoon Haiyan
- central Leyte on the 7th of November
- northern Cabu and Panay on the 8th November
- Vietnam on 11th November
Primary effects of typhoon Haiyan
- 200mph winds
- 400mm of heavy rainfall flooded, 1km inland
- 5m storm surge
- 1.1 million houses damaged
- 1.1 million tonnes of crops destroyed
- power was interrupted
Secondary effects of typhoon Haiyan
- oil barge spilled 800,000 litres of oil contaminated and 10 hectores of trees
- fishing have to stop due to contamination
- flooding caused water to be contaminated causing disease
- 8 people were trampled to death from a Stampede of people trying to get rice supplies
- Rice prices had risen by 11.9 percent by 2014
Immediate response to typhoon
Haiyan
• President televised a warning
• 800,000 people were evacuated to a stadium in Tacloban then died when it flooded
• Government sent out supplies
• emergency aid arrived 3 days later with
1 million food packs and 250,000 litres of water
• countries raised an overall US$1.5 billion
Long-term responses to typhoon
Haiyan
- They have no build zone along the coast in eastern visayas
- New storm surge warning system
- Mangroves were replaced
How do you satellites help reduce the effect of tropical storms ?
• detects a classic cloud pattern associated with tropical storms
