7.1 How have cities grown and what challenges do they face?

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1 7.1 How have cities grown and what challenges do they face? a The world is increasingly urbanised as cities grow due to different processes. Examine urbanisation trends globally and across different regions, including reasons for growth (migration and internal growth). Across the world the number of people living in cities has increased dramatically (it will rise from 3.6 billion in 2011 to 5.1 billion in 2030). The graph below shows the rate of the increase from 1950 to 2007, and the forecast for Migration- People are leaving rural areas due to push factors (lack of jobs and facilities, global warming, mechanisation of farming) and are being pulled to the city by pull factors (jobs, entertainment and educational facilities). Internal Growth- large numbers of young people live in cities, there is therefore a high fertility rate. This means people in cities are having children and causing growth from within the cities (known as internal growth). 1

2 Contrast the economic activities, spatial growth and population of megacities (cities with more than 10 million people) in the developed and developing world. Developing world Megacities Economic activities-manufacturing, financial (banks) and service industries often base here, especially TNC investment, an example is call centers in Mumbai. There are also large amounts of informal employment. Spatial growth- more complicated layout as planning controls are weak, areas often blur into each other and the city is disorganised. There are squatter settlements on any free land round the outskirts as people are moving to be near the CBD (central business district) to get jobs. People build along roads; this is why there is a commercial spine. Population- High fertility rates (large numbers of children per woman) High natural increase (the birth rate is higher than the death rate therefore the population naturally increases without migration) Large amount of over 25 s Developed world Megacities Economic activities- Most developed world Mega cities are world cities, this means they are usually the base of manufacturing, services and industries. Most World cities have a stock exchange e.g. London. TNC s are found there (Transnational Corporations). They have a large amount of tourism. There are entertainment industries such as ballet, night clubs and theatres. They usually have TV companies, airports and ports. 2

3 good schools. Spatial growth-cities are well planned and organised due to planning controls (governments are well organised). The central business district (CBD) is full of offices and shops; this is surrounded by the inner city. The inner city has factories (land for factories is too expensive in the CBD). The inner city also has cheaper, usually run down houses, people who work in the low paid CBD and factories live there. People with well-paid jobs live in the suburbs where it is mainly houses, with supermarkets for convenience. People choose to live here for access to green space, better quality air and Population- Large amount of older people, low fertility rates and low rate of natural increase (because people are not having many children there are less young people in the city than in developing countries. b Cities face a range of social and environmental challenges resulting from rapid growth and resource demands. Examine urban challenges in the developed world, including food, energy, transport and waste disposal demands that may lead to concentrated resource consumption. Developed World Case Study : London Food demands-transporting food into London from elsewhere in the UK, e.g. Cheshire potatoes, or the World, e.g. Kenyan green beans, adds to London s carbon footprint. Food in transported by rail, road and boat (in containers) or air. People in areas such as Camden in London are trying to counteract this by growing their own food on allotments. Energy demands-with such a high population in London alongside a concentration of shops, entertainment and businesses, power stations across England contribute to London s energy. Energy in London comes from Nuclear power, coal power plants and wind farms. 3

4 Water- each London resident uses 161 litres of water a day; this is much higher than the UK average (149 litres). A desalination plant (a factory to take salt out of water) has been built so residents can drink water taken from the River Thames, and water is transported from reservoirs elsewhere in the UK. Londoners use more water as so many of them are single and therefore cook, wash up and clean laundry in smaller loads using the same amount of water two people would need. Transport- 8.6 million people currently live within the city of London, and this rises every day. Many motorways link directly to London, however the roads are overcrowded. 3 million cars, 85,000 buses and 18,000 black cabs are owned and are located within London. Traffic jams, air pollution and noise pollution are major issue because of this. 22% of London s carbon dioxide comes from road traffic, the congestion charge has cure nitrogen dioxide levels by 13% and 80% of the congestion charge pays for public transport. Waste disposal demands- Landfill costs London 280 million per year. This landfill generates methane as it rots contributing to global warming. London provides each household with recycling facilities and are investing in educational materials such as leaflets and websites to reduce the quantity of waste going to landfill. Concentrated resource consumption- There is a huge concentration in the consumption of resources including fuel for transportation, food and water within London as there is such a high population in the city. Drastic measures have to be, and have been implemented to deal with this, e.g. during water shortages hose pipe bans are in place, the roads are congestion charged to reduce fuel consumption and encourage public transport uptake and councils such as Camden educate their residents on recycling and reducing their electricity consumption with measures such as turning appliances off at the plug. 4

5 Examine urban challenges in the developing world, including slum housing, the informal economy and urban pollution, that lead to low quality of life. Developing World Case Study :Rio de Janeiro Informal economy- The informal sector or informal economy is that part of an economy that is not taxed, monitored by any form of government. This leads to a low quality of life as people have no guaranteed income, often work long hours and are at risk of prosecution. They have no health insurance and can t often afford necessities such as school fees or rent. An example of the informal economy is in the Rochina slum, Rio de Janeiro, Brazil, people sell cocaine, cut hair and run child care facilities illegally, many also hawk or sell items such as fake designer clothes on the streets of Rio. Slum housing- A slum is a heavily populated urban informal settlement characterised by substandard housing and squalor. Slum housing is often used to describe squatter settlements. They are found in run down inner cities in developed countries (slum housing was a problem in Liverpool in the 1980 s) and widely across cities in the developing world. These areas lead to low quality of life because people don t have running water, sewage disposal, and electricity, they live in dangerous buildings that can collapse. An example of this is Rochina slum in Rio de Janeiro. Urban pollution- Urban pollution is widespread in developing countries. Many people have older cars which are less economical, roads are not wide enough creating traffic jams and people have an unreliable/ no electricity supply, which results in widespread use petrol generators. All of these issues create air pollution. A lack of sewage pipes, slums and leaks mean that water is often polluted with sewage. This has caused a loss in species such as fish who can be killed by this pollution. People in slums often dump rubbish in and wash their clothes in rivers, as there is nowhere else to do these activities and the river washes some of the pollution elsewhere. There is also less monitoring of factories meaning toxic chemicals are often leaked into water supplies. Uncovered water attracts mosquitoes, which can give people malaria. Drinking dirty water can give people cholera and dysentery. 5

6 Water supply-issues with the water supply are outlined above. Many poorer people do not have piped water to their homes and therefore rely on water pumps (which will eventually run out when there is no groundwater left) or have to drink contaminated water from rivers. 1 billion people globally (1/7 people) do not have access to clean water, this causes deaths daily and creates poverty with missed work and having to pay for expensive medicenes. 7.2 How far can these challenges be managed? a Cities in the developed world have huge potential for reducing their environmental impact(eco-footprint). Investigate why eco-footprints vary from city to city and assess how one named city in the developed world is lessening its eco-footprint by reducing energy consumption and waste generation. London is lessening its Eco footprint by: Reducing energy consumption and reducing waste generation- Launched in November 2009, Small Steps, Big Difference is a brand name covering all Camden's sustainability services. Camden residents are able to access free and impartial environmental advice across a wide range of sustainability issues, including growing their food, re-using clothes and home insulation. The scheme encourages residents to identify areas of their lives which they could modify to lessen their environmental impact. These can be submitted as a 'green promise' from a range of behaviours across 10 themes, including water use, energy consumption, travel, food and recycling. The green promise has received celebrity endorsements from Emma Thompson, Arlene Phillips, Ben Elton, Sean Bean and Ester Rantzen. Energy consumption has been reduced by providing residents on information on how to reduce their electricity use including turning down the thermostat, turning appliances off at the socket and line drying clothes instead of tumble drying; over 24% of London s eco footprint is electricity use, reducing consumption could cut down the Eco footprint. 6

7 In London restaurant s cooking oil is recycled into Taxi biofuel to reduce waste and fuel consumption. Only 16% of household waste is currently recycled, by providing all Camden residents information on how to recycle more and reuse in a way that benefits them London is cutting down its waste. Every home has recycling bins that are collected more than the landfiull bin, meaning residents are often forced to recycle when they run out of bin space. Eco footprint- How many planets would we need if everyone lived like you? An ecological footprint measures the total amount of land and resources used, it includes your carbon footprint but goes further. Carbon footprint-the amount of carbon dioxide released into the atmosphere as a result of the activities of a particular individual, organization, or community. Analyse the potential for more sustainable transport in a named city in the developed world (London). Boris Bikes-These bikes are free to rent for 30 minutes and very cheap after this time. They are found across London and near tube stations, encouraging people to bike rather than tube/ taxi or driving across town. They get rid of the problems of parking and locking up a bike, and storage as many London flats are small. This is sustainable as it doesn t use oil, therefore preserving oil for the future. London Underground- The London Underground train system bypasses the on street traffic by traveling underneath the ground. It links up with many areas around London and gives people a quick, easy way of traveling. It is sustainable as if all of these people drove a large quantity of air pollution would be created and a large amount of oil would be used. It is cheap and it is the quickest way to travel around London. Congestion charging- Cars are charged to enter and drive within the city of London, this money is spent on the Boris Bikes and London Underground. This is sustainable as it discourages car use, trains use much less fuel than if all the people on them drove. 7

8 b Different strategies can be used to manage social and environmental challenges in developing world cities. Consider the success of strategies to improve quality of life in cities in the developing world: self-help schemes, the work of NGOs, urban planning (e.g. Curitiba). Self- help scheme- Rocinhna, Rio de Janeiro, is home to a self= help scheme designed to make life in the favelas (slums) safer. Rochinha is built on steep slopes, like many slums, and during heavy rain there are often dangerous landslides which destroy homes. People s homes are made of plywood (thin, easily breakable wood). People in Rocinhna have been given breeze blocks, cement and building lessons so that they can build their own safe homes. It costs very little as locals are doing it themselves and breeze blocks and cement are cheap to buy. Non- governmental organisations (charities, NGOs)- In Sri Lanka the Urban Green Partnershop have helped residents in Badulla by making 100 home gardens, where people can grow food to feed themselves. The council are now building green space into every new building. Urban planning- Case study Curitiba The large amount of green space and accessible buses in Curitiba has cut pollution as fewer people drive, this has improved life as the air is cleaner, Residents love having access to the park for jogging, football and walking places if they are short on money. The buses are cheap so people can afford to travel around town. Slum housing is being slowly improved and good quality apartment blocks are being built to house large numbers of people. Large areas of the city are pedestrianized (walking only) to allow residents to walk and make a nice atmosphere in these areas. Sheep are used to keep the park s grass short, to avoid petrol, noisy, lawn mowers. The park helps to absorb water and reduces flooding, the river runs through the park, meaning the park, not homes, is flooded in heavy rain. 8

9 Evaluate the advantages and disadvantages of attempts to develop lesspolluted cities, e.g. Mexico City. By 1998 the United Nations said Mexico City was the most dangerous city in the world its air was so polluted, 100 deaths and 35, 000 hospital admissions were caused in the city by air pollution in Air pollution Problems: Mexico City is surrounded by mountains which trap air pollution within the city. Nitrous oxides become nitrogen dioxide in the sun which is toxic. Ozone is created by car emissions, it makes the body sensitive to pollen and dust and causes hay fever. Carbon monoxide from poorly maintained cars makes people tired and causes headaches. Sulphur dioxide from car exhausts causes breathing problems. Solutions: The government funded spare parts to make buses more reliable (so people would use them) and reduce the pollution given off by buses. New laws making petrol and diesel recipes less polluting. Underground train to speed up public transport and encourage use. Ecobici (Boris bike) bike share scheme. Waste Problem: Mexico City produces 13, 000 tonnes of rubbish per day. Landfill pollutes the city s water supply. The landfill sites are full. Rubbish mountains built up as the landfill was full. Water ways were blocked due to fly tipping (when people dump their rubbish in the river). 9

10 Solutions: New landfill created. People educated about recycling with leaflets and bins provided. Composting encouraged. Incinerator built to burn waste and generate electric. Water Problems: Underground water (aquifers) are over abstracted from (too much water taken). This is causing the city to sink and water and sewage pipes to burst and crack. Not enough recycling of water. Not enough sewage plants. 320 litres of water used per person, per day (much higher than London). Solutions: New sewage works built. Rainfall collection tanks. 10% of water now recycled). Even deeper aquifer use. 10

11 Advantages of developing a less polluted Mexico City Water: 1. Building sewage works reduces water pollution. 2. Saving rainwater reduces aquifer usage and over abstraction. 3. Recycling water reduces aquifer use. Waste: 1. More recycling reduces landfill. 2. Burning waste reduces landfill and therefore reduces water and air pollution. 3. Landfill and bin collections will reduce fly tipping and the blocking of rivers. Air pollution: 1. Repairing buses reduces air pollution and increases trust in the service so more people use it. 2. Changing fuel recipes has reduced pollution emited from cars and buses. 3. Ecobici (bike share) has reduced fuel use. Disadvantages of developing a less polluted Mexico City Water: 1. Sewage works are expensive. 2. Home tanks are easily polluted by animals and insects. 3. Only so much water can be recycled. Waste: 1. Not everything can be recycled and many people refuse to recycle. 2. Burning waste still pollutes the air and much can be recycled, resources such as steel will run out if not recycled. 3. Adds to air pollution (methane given off). Mexico City will eventually run out of space. 1. Buses are expensive to repair and will eventually break. 2. The new fuel recipe is more expensive, some people say the money should have been spent improving cars. 3. People with a long journey or not near a bike point cannot use this service. 11