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Urban Environments

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IB Geography, urban environments shanty town, kigali, Rwanda

Read this article for an introduction to the unit: megacities. Published by http://www.yearofplanetearth.org/

Centripetal Movements

Inward movements of people (centripetal movement)

Urbanisation: An increase in the % of a countries population living in towns & cities.

Rural to Urban Migration

rural to urban migration

You should be able to explain the push and pull factors & discuss extra factors such as the importance of remittance payments.

Centrifugal Movements

Outward Movements of people (centrifugal movement)

Suburbanisation: The growth of towns & cities to include (engulf) surrounding villages/ rural areas.

Urban Sprawl: Unplanned & uncontrolled spread/growth of a city into the surrounding rural area.

Counter-urbanisation: The movement of population away from inner urban areas to a new town, a new estate, a commuter town or a village on the edge or just beyond the city limits/rural–urban fringe.

counter urbanisation push and pull factors

Decentralisation: the movement of retail and services (shops and offices) to out of town or edge of town locations.

decentralisation push and pull factors

Global Megacities

Global Megacities: cities with a population over 10 million.

Mega-city Growth interactive diagram (Guardian 2012)

Where and why have these cities been rapidly increasing in number? What are some of the problems that they are facing?

Growth of modern cities (podcast) 2011

IB Geography urban environments San Jose, Cosat Rica

Land Use Models

Concentric Ring Model: Burgess, based on Chicago

concentric ring model
Fig Concentric Ring Model

You should be able to explain the pattern shown in the model and identify its weaknesses.

Sector Model: Hoyt

This model introduced the idea that lines of transportation would have a significant impact on land-use zoning. Industry is likely to locate along routes of transportation (road and rail) to receive raw materials and to deliver the final product.

Workers in these industries were likely to live close the industries (lack of transport and perhaps accomodation provided by the industries).

Hoyt sector model daigram
Hoyt Sector Model

Brownfield Sites

Definition: Abandoned, derelict or under‑used industrial buildings and land that may be contaminated but have potential for redevelopment.

Tasks

Read factfile - UK brownfield sites

Why are brownfield sites often more expensive to develop than greenfield land?

UK brownfield development issues (2001)

Example 1:London Olympic Park

Read the following articles and make notes about the site of the olympic park - where, clean-up required, benfits to the area: pdf article, olympic site.

Example 2: Battersea Powerstation, London

Read this Guardian article and watch the video opposite, make short notes about what the original use was and the new land use due to redevelopment.

What are the concerns about the redevelopment of the powerstation?

Greenfield Sites

LEDC City problems & solutions - favelas/slums

CASE STUDY: Rocinha, Rio de Janeiro

Go this page: Rio Case Studies

Make notes about the favela in Rio -

  • What are they?
  • Where are they?
  • Why do people live in them?
  • What services do they have?
  • What rights do they get/have?
  • What sense of community is there?
  • How the authorities cope with them?

The Formal Job Sector

This is the official sector of employment. Workers benefit from regulated hours, holidays and sick pay. They contribute to state pensions and benefit from social security policies.

Working in the formal sector makes it much easier to secure bank loans (buy cars, houses, start businesses etc).

The formal sector is more difficult to enter - workers usually need evidence of education or qualifications and a recognised permanent address. A bank account is also neccessary for getting paid in most cases.

formal employment taxi driver
Formal Employment: New York Taxi Driver

The Informal Job Sector

This is the unofficial sector, is wide ranging and plays an important role in many urban areas.

The formal sector lacks the financial security of the formal sector, is unregulated in terms of working conditions and safety. Workers in this sector dont contribute to state schemes such as pensions and health care.

Despite the risks of being employed in the informal sector it provides much needed opportunity for many of the poorest residents, especially those in slums/favelas.

In LEDCs the informal sector plays a vital role in recycling waste material and reducing the waste going to landfill sites.

Read this article

  1. Describe the scale of the informal sector in Columbia
  2. Describe the problems faced by workers in this sector
  3. What benefits of working in this sector are mentioned?
  4. Explain how the informal economy can offer a route out of poverty for people.
informal sector
Informal Employment: Fake DVD selling in Costa Rica

Urban Heat Islands

You should be able to explain the causes of higher temperatures and modified local climatic features in urban areas.

Factors such as the change in the albedo rate due to roads and buildings, the heat released from transport, the leakage of heat from buildings (heating and air conditioning).

Other factors to consider are things such as changes in the levels of humidity due to the loss of vegetation and the rapid draining of surface water out of the area. Changes in wind speed and flow due to building design (Chicago is a good example).

  1. Use this link to explain in more detail the causes of urban heat islands.

 

New York Urban Landscape
Fig New York Urban Heat Island Factors

Urban Stress

Urban areas suffer from pressure due to their nature of dense populations.

  • Crime: increased levels as rich and poor live in close proximity and there are often extremes of both rich and poor.
  • Traffic congestion: rapid urban expansion and the increase in car ownership has left many urban areas struggling to keep traffic flowing.
  • Air pollution: air pollution in many cities has been deteriorating. Industry, car ownership and in many developing urban areas the use of charcoal for cooking all contribute. Beijing Smog
  • Refuse: urban areas produce vast amounts of domestic and industrial waste. Developed countries increasingly invest in collection and recycling of domestic waste. In many developing countries official waste collection does not function as effectively and pollution is an increasing concern.
  • Housing: rapid rising demand often outstrips the ability to increase supply of housing. This results in price increases (London) and/or illegal settlements emerging (favelas in Rio).

Guardian 2015 article looking at the patterns of use and urban stresses for 4 major global cities. Some good information about comparative densities and transport networks.

You should be able to describe and explain examples of urban stress, supporting your answers with examples.

Use the videos and links to make case study notes.

traffic
Traffic congestion: Kigali, Uganda
Video
Video

Cities around the globe in both developing and developed countries are facing many challenges due to their size and the resources that they consume.

Their populations are increasingly aware of the health issues caused by pollution (water, air and and noise). International agreements have been established to reduce different types of pollution and fines for failure may be imposed. Traffic congestion, over-crowding ,poverty and crime are examples of social issues that need to be addressed to improve the functioning of urban areas.

The City a System

Linear City Systems

inputs—energy, water, people, materials, products, food

outputs—solid, atmospheric and liquid waste, noise, people.

Inputs are consumed and waste sent for disposal, ususally in landfill or incineration.

IB Geography, urban environments, linear city systems

Circular City Systems

Reducing, reusing and recycling the resources that the city consumes lead to less inputs and less outputs, shrinking their urban ecological footprint and increasing their sustainability.

This circular approach can be applied by households, industry and local governments/councils.

Be able to discuss strategies and impacts with examples.

IB Geography, urban environments, circular city system

Sustainable Cities

Ecological Footprint

The theoretical measurement of the amount of land and water a population requires to produce the resources it consumes and to absorb its waste under prevailing technology.

  1. what is it, how is it measured,
  2. how can cities reduce it etc.

In your groups research & present back a powerpoint or movie Case Study.

It should be no longer than 5 minutes, .
Curitiba (Brasil), Calgary (Canada) - examples of sustainanble measures introduced & further plans.

Urban ecological footrprint webpage (just to get you started).

IB Geography, Mwanza skyline, urban environments

Sustainable Strategies: London, UK

Sustainable Pollution Management

London suffers from air pollution which exceeds the European Union regulations many times a year. One of the main contributers is transportation and London is aiming to reduce traffic emmisions through a number of initiatives.

It has an extensive underground electric train system which helps since the electricity is produced outside the urban area.

Use the links and watch the video to compile a case study about the ways in which London is attempting to reduce air pollution.

  1. Describe the air pollution issue: London Air Pollution problems (Guardian.co.uk, 2010)
  2. Make notes about the following initiatives.

Excellent graphics here for some of the sucesses

 

Urban Regeneration: Docklands

good information here

CASE STUDY: Thames Gateway

Thames Gateway

Socially Sustainable Housing: Singapore HBD

P.450/1 Waugh - notes about:

  • Existing problems
  • What is the HDB & what has it done.
  • In what ways are the projects socially sustainable?

Eco-cities

Tianjin Eco-City

BBC video & BBC article

  1. Watch & read & make notes about the aims of the city.
  2. In what ways is it sustainable?
  3. What challenges does it face?

 

Eco-City examples (videos)

Past paper Q

IB geography revision guides link