tropical storms - Pearson Schools and FE Colleges

Transcription

tropical storms - Pearson Schools and FE Colleges
tropical storms:
where and how?
Is there such a thing as a typical tropical storm? A tropical storm is typically 700km in diameter
Tropical storms are amongst the most powerful
and destructive meteorological systems on earth.
Globally, 80 to 100 develop over tropical oceans each
year. Many of these can cause considerable damage
to property and loss of life.
A tropical storm is a large depression that forms
over tropical oceans and moves away from the
equator. Ocean temperatures must exceed 27°C for
a tropical storm to form and the water needs to be
at least 60m deep. The wind speeds are usually in
excess of 74mph. Tropical storms happen during
the hottest times of the year – between May and
November in the northern hemisphere and between
November and April in the southern hemisphere.
Areas that are susceptible to tropical storms are the
Caribbean and Central America, South East Asia and
the Indian subcontinent.
and can exceed 13km in height. In the northern
hemisphere the winds rotate in an anti-clockwise
direction. Fast-rising warm air creates an area of
very low pressure – the eye of the storm – which
sucks in air. The rotating winds cause low pressure
close to the equator and absorb the moisture from
the oceans creating hurricanes and cyclones.
research link
How do tropical cyclones get their name? Go to the
supporting website www.heinemanngcsegeogocrB.co.uk
for some links where you can find out the answer.
key WorDs
Hurricane: a type of tropical storm with a violent wind
Cyclone: a system of winds rotating inwards to an area of low
pressure
where and when tropical storms take place
2 OCR GCSE Geography B
A section through a typical
cyclone or hurricane
How tropical storms effect people and places
Tropical storms can cause great damage when they reach land. They
can damage buildings, power cables and crops. Flooding can be caused
by the heavy rainfall brought by a tropical storm and also through
storm surges.
An MEDC is better placed to deal with the effects of tropical storms.
They have technology, such as weather satellites, to enable them to
monitor and predict storms and have well-equipped infrastructure to
deal with them when they do strike. This infrastructure includes things
such as emergency procedures, resources, robust transport and food
supplies,. Often in LEDCs people don’t have the means to move inland
away from the storm and therefore the impact is usually greater.
Plenary activity
Why do MEDCs suffer billions of pounds worth of property damage but LEDCs
lose hundreds of lives in tropical storms?
think about it
Is climate change affecting tropical
cyclones?
Fact file!
• The deadliest hurricane on
record was the Martinique
Hurricane of 1780 that killed
20,000 people.
• Hurricanes Camille (1969) and
Allen (1980) share the record
for the maximum sustained
windspeed for an Atlantic
hurricane of 16 knots (306 kph).
key WorDs
Storm surge: When low pressure
and high winds cause the sea to rise,
sometimes by over five metres, which
leads to coastal flooding
Tropical storms: where and how? 3
Case Study Cyclone Nargis, 2008.
Are the deaths from tropical storms caused by being in the wrong place at the wrong time?
Myanmar area
Any country not used to being struck by winds of
over 100 miles per hour and torrential rain is going
to suffer but when that country is already poor the
effects are much worse. Factor in a government
suspicious of help and long term destruction of
natural defences and a disaster now appears to have
been waiting to happen.
In late April 2008 an area of very low pressure
formed in the Bay of Bengal. The American Typhoon
Warning Centre in Hawaii monitored the storm as it
got worse and moved north towards land. Satellite
images on 29th April showed that a tropical storm
had formed. Forecasters predicted that the storm
would hit Bangladesh but as its strength ebbed and
flowed due to changes to the sea water temperature
its course changed towards the coast of Myanmar.
Myanmar
Myanmar is a Less Economically Developed
Country (LEDC) with a population of about 55
million. It is one of the poorest countries in South
East Asia with restricted development, mainly due
to issues with the ruling military government and a
desire to be isolated from the world.
Myanmar relied heavily on primary exports like
oil and expensive timber but a lack of roads and
railways mean that the government has been unable
OCR GCSE Geography B
to fully exploit their natural wealth. However,
Myanmar is still the world’s largest producer of
rubies, although the average Burmese citizen doesn’t
benefit much from this trade, with a GDP per capita
of £1900 and a Human Development Index (HDi)
of 0.578. In a country with the same size population
as the UK there is only 1 person in a thousand with
access to the Internet. Myanmar ranks 32nd in a list
of the world’s 50 poorest countries and the last thing
it needed was a disaster the size of Cyclone Nargis.
Environmental damage in Myanmar
As is often the case with the world’s poorest
countries, the environment suffers in order for
money to be earned. In Myanmar’s case this has
meant the destruction of mangrove swamps. In a
75 year period Myanmar has destroyed 83% of its
mangroves in the area affected by Cyclone Nargis.
These mangroves should have served as natural
barriers to stop storm surges. Their root systems slow
water flow, catch material and absorb wave energy.
In the 2004 Boxing Day tsunami, villages with intact
mangrove swamps had suffered significantly less
death and destruction than those that had lost theirs.
However mangrove swamps get converted into
money-making areas such as shrimp farms, tourist
resorts, land for agriculture and re-housing.
The effect of the storm
By 2 May the storm’s winds had reached speeds of over 135 mph and it
hit the vast delta of the Irrawaddy River in Myanmar bringing torrential
rain and storm surges to the very low-lying and agricultural delta.
The United Nations estimated that 1.5 million people were severely
affected by Cyclone Nargis, with official figures estimating the death
toll at over 125,000 people. Some reports suggest 95% of buildings were
destroyed, and all suffered significant damage including roofs being
ripped off. Millions of people were made homeless as a result of the
storm. The local infrastructure was unable to withstand the storm with
reports that sewage systems were overwhelmed, causing leakage which
contaminated rice fields and caused disease. Electricity lines were also
destroyed, roads were swept away and stagnant, dirty water encouraged
vast numbers of mosquitoes to breed.
The biggest impact was not from the high winds but from the flooding.
Low pressure meant that the sea was no longer depressed by the
atmosphere and so the sea level rose. As a result the low-lying coastal
areas of the Irrawaddy River were flooded. The short-term effects were
that people drowned and many were made homeless. In the longer
term fields were destroyed, families were devastated and development
was put back by years.
The response to Cyclone Nargis
As the scale of the disaster became clear it also became apparent that the
military government of Myanmar was not doing as much as the rest of
world thought it could. Stories leaked out of aid being kept in the major
cities and not spreading out to rural areas. Foreign aid workers were
either not allowed in to help or were restricted in where they could go.
More than a week after the cyclone first hit only one in ten of those
affected had received some sort of aid. MEDC governments loudly
accused the Burmese government of making the situation even
worse. The army harassed volunteers, check points on rivers stopped
journalists from covering the disaster for television, leaflets were
distributed to inform people that aid deliveries are only attracting
children and others who do not need help. What lies behind these
tactics is hard to say, but experts suggest that it is an attempt to
preserve the prestige of Myanmar within its own boundaries and
across the world preserve the prestige of Myanmar within its own
boundaries and across the world.
Remote sensing image of Cyclone
Nargis as it reaches the Irrawaddy
Delta.
think about it
Much of the anger of the Western
governments has been used to
highlight previous human rights
abuses in Myanmar and the lack of
democracy in the country. This has
meant that the Burmese rulers have
been even slower to let foreigners in.
Should the UK government have
done anything other than send in
supplies to help?
Activities
1.What were the physical factors
that made Cyclone Nargis so
destructive in Myanmar?
2.Why did some many people
choose to live in such a
potentially dangerous area as
the Irrawaddy delta?
4.What things would Myanmar
need after a disaster like Nargis?
How would they change as time
went by?
Plenary Activity
The Irrawaddy Delta before and immediately after Cyclone Nargis. Notice how much
is now under water.
If you were in charge of defending
Myanmar against future cyclones
what would be your priorities? How
would you go about putting them
into action?
Tropical storms: where and how? a decision Making exercise –
a sustainable Future for town Centres
In this exercise you will be asked to reflect on Government policy for creating
sustainable retail development town centre locations, at the expense of “out-of-town”
locations. Read the Fact File below and then make your decision. More contextual
information is available on the CD-ROM to help you develop your ideas further.
PEARSON NEWS
January 2008
Town Centre First – The case against
new out-of-town shopping centres
In May 2006 the Department for Communities and Local Government
re-emphasised their policy to promote town centres, ahead of outof-town locations, for new retail development. Whilst the policy
remains unpopular with large retail giants like Tesco, Sainsburys,
IKEA and Comet, the Government are determined to create vibrant,
sustainable retail communities in the heart of our towns and cities.
The policy was developed following years of decay in town centres
as the large retail giants looked for new, often Greenfield sites, out
of town. Government ministers were also increasingly concerned
about the negative impact on small retailers such as butchers and
grocers in adjacent suburbs. Legislation was passed to ensure that
councils consider town centres first. Councils were instructed to
refuse planning permission for out-of-town locations if land was
available in the town centre. From 2006, all planning authorities
were required to sequence their planning permission in favour of
town centre sites.
v
Why large retail stores
prefer “out-of-town
locations”
Why town centres
have faced decline in
recent years.
High car parking charges
tend to put off shoppers
Roads leading to the
centre tend to be
congested, particularly
in the rush-hour
6 OCR GCSE Geography B
However, thousands of planning applications for out-of-town sites
are still being made. This puts pressure on planning departments.
Not only do the large retail giants want to move out of town, it
seems that shoppers prefer to shop there. The Federation of Small
Businesses recently carried out an extensive survey of public
opinion. Members of their organisation should be worried, as 75%
of all shoppers who were asked said they preferred shopping in
large stores out of town.
The sites are adjacent
to the suburbs where
our customers live.
The sites are often adjacent to junctions
giving access to major trunk roads.
This keeps down distribution costs.
Roads leading to the site tend to be less
congested and wider. This is perfect for
our customers and our deliveries.
The policy has had an impact. In February 2007, Friends of the Earth
reported a number of cases where permission to build “out of town”
had been refused. In 2004 attempts by Asda and Tesco to build large
stores in deprived areas outside Middlesbrough were refused on the
grounds of a negative effect on town and district centres. There were
sequentially preferable sites in the town centre. In 2006 the Planning
Inspector ruled that Asda’s plan for developing the site at Worthing
College should be denied, as it was not in the town centre.
High land values,
high rents and high
rates are not ideal
for large stores
Pedestrianisation
schemes along with
narrow streets create
real difficulties for our
large delivery vehicles
Land and the cost of rates tends to
be cheaper than in the town centre
Large vacant sites can accommodate
the Superstore large car parks, petrol
stations, and efficient delivery depots.
Car parks are not always close
to the shop. This is difficult
when you have large items
There is a “tipping point”. Once
several shopping units become
vacant, there is a spiral of decline
and even more shops leave.
The vacant Civic Centre in Ipswich
The vacant Crane site on
the SE edge of Ipswich
When the former Civic Centre site became available
(above), it was always going to be selected for
development ahead of the redundant Crane Works
on the SE edge of Ipswich (right).
PEARSON NEWS
August 2008
New Retail Plans for redundant site in
Ipswich Town Centre
In February 2008 Ipswich Borough Council (IBC) produced a final
version of their Local Development Framework (LDF). The aim was
to promote sustainable growth in the town. Developed over a number
of years, the LDF outlines the need to utilise town centre sites ahead
of other locations. This would ensure a vibrant town centre for future
generations and bring a halt to the decline of the CBD. Retailers have
closed or moved out to other favoured locations.
As early as 2005, IBC carried out a Retail Study to ensure that
their Framework would reflect Government policy. DTZ, experts in
retail development, reported that the Council should develop town
centre sites, such as the Westgate Quarter, ahead of vacant plots
on the edge of town, such as the former Cranes industrial site.
This would comply with National Policies.
When the former council offices at the Civic Centre were vacated
in 2007, it was no surprise that Council granted permission for
Turnstone Property Developments to promote the site for retail
development. This would be at the expense of developing retail
outlets at sites such as the former Cranes works. The decision
might fit the sustainable credentials of IBC but it would not prove
popular in the eyes of retail giants who seek to develop their
businesses out of town.
your task:
Consider the evidence on these pages and the information on the supporting CD.
Write two letters to the editor of the Ipswich Evening Star regarding the plans to
develop the town centre of Ipswich ahead of sites such as the Crane site.
• Your first letter should state the views of a person who fully supports IBC’s
policy to regenerate the town centre.
• Your second letter should state the views of someone who is opposed to the
policy of prioritising town centre development.
think about it
In class, debate which of
the two views you think
is the strongest. Try to
relate the Ipswich case
study to a dispute about
retail developments in
your own area.
Tropical storms: where and how? 7
GradeStudio
Mark scheme for question 3
Level One
The student understands that LEDCs do find it harder because
they have less money. One or two examples are given of when
this has happened.
[1–2]
Level Two
The student is able to describe some of the problems caused by
hurricanes and explains how money is a factor in the degree of
impact a storm has.
[3–4]
Level Three
The student is able to explain with a high degree of clarity and
detail how this is the case citing examples they have studied.
The arguments are logical and extended.
[5–6]
Part of the Student answer for
question 3
3. Suggest reasons why Less Economically Developed Countries find it
harder than MEDCs to
recover from the effects of a tropical storm.
[6 marks]
LEDCS find it harder to recover because they do not
have as much money and so are less developed. This
means that they are less able to help their people when
disaster strikes.
For instance, in some cyclones the government does
not have many helicoptors so they were unable to help
as many people as they could have done. Being poor
often means that a lot of people work in farming and
cyclones with their high winds and flooding destroy
crops. This means that people lose their livelihoods and
find it hard to survive. It also means that they live in
rural areas which don’t receive as much help as towns
and cities. This is because of a variety of reasons.
8 OCR GCSE Geography B
Examiner says
An A or A* candidate would have mentioned more
than one way that money is an issue. They would have
mentioned detection and prevention methods too.
Examiner says
A higher achieving candidate would have used an
example that they had studied.
A candidate aiming at B or higher would have made
this sentence clearer.
Uses an extended reason to make grade C more likely
but doesn’t use all the terms they might have.