Zusammenfassung der Ressource
Tropical storms .
- What are
tropical
storms?
- A deep
area of low
pressure in
the tropics
- How are
tropical
storms
named?
- There are three names given to tropical storms depending on their location
- Hurricane - Atlantic/ East Pacific
- Cyclone - South east Asia
- Typhoon - Japan/Philippines
- Distribution of tropical storms
- Found close to the equator in a central band but not directly on the equator
- Requirements
for a storm to
occur
- Warm water
i.e. The sea
(27 degrees
and above)
- Summer/
autumn when
the highest
temperatures
are
- A latitude
greater that
5 degrees
north or
south of the
equator (not
enough spin
at the
equator)
- Tropical regions of severe air instability
- Low pressure where there is air rising and as it is moving the conditions are unstable
- (Stable conditions are where there is a heavy air mass which is sinking - cold air)
- Tropical storms are measured on the Saffir-Simpson scale
- Hurricane structure
- Eye wall
- Strongest winds and heavy rain (this decreases in bands as you move further away from the eye wall)
- Eye
- Region of
calm
weather in
the middle
of tropical
storms
- Clear as
sucking air
from above
which is
sinking - this
prevents
clouds from
forming
- Area of
dense air
and
generally
about 15-30
miles across
- Who do tropical storms spin?
- The coriolis effect bends and spins the warm rising air
- Hurricanes in the northern hemisphere bend to the right which causes the clouds to spin anti-clockwise
- Cyclones in
the
Southern
Hemisphere
swirl in a
clockwise
direction
- What direction do tropical storms travel?
- Travel from east to west due to the direction in which the earth spins
- When they hit
land they lose
their energy
source from the
sea that
powered them
- As they lose energy
they change
direction - in
northern
hemisphere track
north and in
Southern
Hemisphere track
south
- Coastal areas are most at risk
- When a tropical storm reaches land it has lost its power source - warm water
- However further in land there can be flooding due to he heavy rain that can last for days
- Formation
- Air is heated above the
surface of warm tropical
oceans - the warm air rises
rapidly under the low
pressure conditions
- The rising air draws up more air
and large volumes of water from
the ocean causing strong winds
- The Coriolis effect causes the air
to spin upwards around the
central eye
- As air rises it cools and
condenses to form large
cumulonimbus clouds which
generate torrential rainfall
- When air condenses
into clouds latent heat
is released (due to
energy in bonds) which
helps to power tropical
storms
- The tropical storm travels
across the ocean in the
prevailing winds
- When the tropical storm
meets land it is no longer
fuelled by the source of
moisture and heat from
the ocean so it loses
power and weakens
- Typhoon Haiyan
- 8 November 2013 at 4.40 am
- Category 5 on Saffir-Simpson scale (155mph+ winds)
- Death toll: 6,190
- Overall cost of damage: US $12 billion
- Struck Philippines (originated in northwest Pacific Ocean)
- Effects
- 14.1 million people affected of which 4.8 million already day lived in poverty
- Total damage US$12 billion - rebuilding required
- Airport badly damaged - trade links and tourism
- Farm land destroyed and crops lost - recovery costs for agriculture and fishing US$724 million
- Responses
- Immediate
- Evacuated 800,000 people
- People died when stadium flooded (meant to withstand winds)
- Essential equipment and medical supplies sent out by governemnt
- Within two weeks over one million food packs and 250,000 litres of water were distributed
- Help from other countries and organisations
- More than $1.5 billion was pledged in foreign aid
- Long-ten
- 'Build back better' scheme to upgrade buildings to be protected in the event of future disasters
- No build zone along he coast in Eastern Visayas
- New storm surge warning system
- Plans to rebuild the Tacloban-Paulo-Tanauan Road dike to protect against storm surges
- Effects, responses and mitigation of tropical storms
- Effects
- Strong winds
- Can demolish houses and destroy infrastructure and wipe out crops
- Tornadoes can also be caused by tropical storms
- Torrential rainfall and storm surges
- Storm surges - when the sea level rises rapidly and particularly high due to the storm
- Cause flooding and can trigger landslides
- Aid is affected as roads are flooded and water supplies can become contaminated with sea water, sewage and industrial waste
- Responses
- Can generally be predicted
- Warning systems provide crucial information regarding strong winds, heavy rain and storm surges which are broadcast to the public
- Allows vital time to prepare and protect property
- Evacuation
- Evacuate to higher ground - away from the impact of storm surges
- Shelter provided by public buildings or nets provided by international aid are also necessary when homes are extensively damaged or destroyed
- Distributing supplies
- Distributing emergency food and water is essential for survivors in the aftermath of a tropical storm
- MEDCs are more likely to have the resources available o do this although during large-scale disasters international help is often necessary
- If there is large scale devastation it can take longer for aid to reach where it is needed especially in remote locations
- Aid may be hindered if roads have become blocked (due to debris/ fallen trees/ flooding)
- Mitigation
- Repairing damage to existing buildings including homes
- Repairing infrastructure and businesses
- Ensuring the country is capable of managing a future hazard by investing in methods of protection and prediction of storms
- E.g. A new early warning system for storm surges or new sea defences