OxfordAQA International A-level Geography (9635): 3.4.2 People and contemporary urban environments – Revision Notes

These are the short-form notes. For full explanations, worked paragraphs and evaluation, read the People and contemporary urban environments study guide first.

They cover section 3.4.2 of the OxfordAQA International AS and A-level Geography (9635) specification, Version 3.2, sub-sections 3.4.2.1 to 3.4.2.9. The specification assesses this content in Unit 4: Human geography 2, Section B, in a 1 hour 30 minute exam where each of the two sections carries 40 marks. Test yourself with the practice questions, and track the whole course on the OxfordAQA A-level Geography hub and the 9635 checklist.

Key terms

Term	Definition
Urbanisation	Rise in the proportion of people living in urban areas
Urban growth	Rise in the absolute number of urban dwellers
Megacity	Urban area of more than 10 million people
World city	City with a major command role in the global economy
Deindustrialisation	Decline of manufacturing employment
Decentralisation	Movement of people, jobs and retail from the centre to the edge
Suburbanisation	Growth of residential areas at the urban edge
Counter-urbanisation	Movement from cities to small towns and rural areas
Urban resurgence	Renewed population and investment in inner areas
Informal sector	Unregistered, untaxed work outside state regulation
Fortress development	Gated, guarded space with controlled access
Gentrification	Renovation of older districts by higher-income newcomers, often displacing existing residents
Edge city	Large office and retail centre on the urban fringe
Post-modern city	Fragmented, multi-centred city with sharp contrasts and privatised space
Urban heat island	Higher temperatures in a city than in its rural surroundings
Photochemical smog	Pollution from sunlight acting on nitrogen oxides and hydrocarbons, producing ozone
Leachate	Contaminated liquid draining from waste
Waste stream	A category of waste with a common origin or material
Morbidity	The rate of illness in a population
Vector	An organism, such as a mosquito, that carries a disease to people
Ecological footprint	Land and water area needed to supply a population and absorb its waste
Liveability	The quality of life a city offers its residents
SuDS	Sustainable urban drainage systems that slow and store run-off

Case facts at a glance

Item	Detail you can quote	One evaluation point
UN World Urbanization Prospects 2018	30% urban in 1950, 55% in 2018, 68% projected for 2050; 33 megacities in 2018	Projections depend on how each country defines “urban”
Ruth Glass, 1964	Coined “gentrification” describing London	Some see gentrification as investment; others as displacement
Joel Garreau, 1991	Edge City: offices, retail, more jobs than bedrooms	Fits US cities best; less common elsewhere
Wackernagel and Rees, 1996	Ecological footprint in global hectares	Simplifies complex impacts into one number
Eko Atlantic, Lagos	About 9 km² reclaimed from the sea; 8.5 km sea barrier	Locals link works to erosion and surges
Makoko, Lagos	Stilt settlement on Lagos Lagoon; July 2012 demolitions left nearly 3,000 homeless	State cites safety; campaigners cite displacement
Olusosun landfill, Lagos	About 40 ha; up to 10,000 tonnes a day; now surrounded by housing	Burning and leachate harm nearby residents
Singapore HDB and Ethnic Integration Policy	HDB formed 1960; close to 80% in public housing; ethnic quotas since 1989	Prevents enclaves but limits sellers’ choice
Singapore waste	Incineration cuts waste by up to 90%; ash to offshore Semakau Landfill (opened 1999)	Needs land-scarce, high-income conditions
Singapore ERP	Road pricing from 1 April 1998	Works with strong public transport
Malaria	Female Anopheles vector; WHO African Region about 95% of cases and deaths (2024); Singapore malaria-free 1982	Urban risk depends on drainage and water storage
Anopheles stephensi	Invasive urban vector found in Djibouti around 2012	Breeds in containers, so rural-style control is weaker

Must-know distinctions

• Urbanisation versus urban growth: a proportion versus an absolute number.
• Megacity versus world city: size versus global economic function. Singapore is a world city but not a megacity.
• Suburbanisation versus counter-urbanisation: moving to the urban edge versus leaving the urban area.
• Formal versus informal sector: registered, taxed work versus unregistered work.
• Fortress development versus gentrified area: built to exclude versus an existing area changing occupants.
• Particulate versus photochemical pollution: solid particles from burning and dust versus ozone from sunlight on exhaust gases.
• Incineration versus landfill: volume reduction and energy recovery versus cheap burial with methane and leachate.
• Communicable versus non-communicable disease: malaria (vector-borne) versus asthma (not infectious).
• Mortality versus morbidity: death rate versus illness rate.
• Sustainability versus liveability: long-term environmental, social and economic balance versus present quality of life.

Urban climate in one view

Element	Urban effect	Main cause
Temperature	Warmer, especially calm clear nights	Heat storage, waste heat, less evaporation
Precipitation	More frequent, intense convective rain	Rising warm air, extra condensation nuclei
Fog and thunderstorms	More fog; more summer storms	Nuclei; strong heating
Wind	Lower average speed; local funnelling and gusts	Rough surface; canyon effect
Air quality	Particulates and photochemical smog	Traffic, industry, burning, sunlight

Mini essay plan

Question type: “With reference to two contrasting urban areas, evaluate the success of strategies to manage environmental problems.”

1. Introduction: define environmental problems (air, water, drainage, waste, dereliction). Name both cities. Set the criterion: success means lasting improvement for all residents, not only the wealthy.
2. Singapore, waste: incineration and Semakau. Strength: up to 90% volume reduction and energy recovery. Limit: landfill space is finite and incineration still needs ash disposal.
3. Singapore, air quality: ERP since 1998 manages congestion. Strength: linked to good public transport. Limit: pricing alone does not cut regional haze or all emissions.
4. Lagos, waste: Olusosun landfill. Limit: burning and leachate harm surrounding residents. Context: rapid growth outpaced planning.
5. Lagos, transport and drainage: BRT from 2008 and the Blue Line from 2023. Strength: alternatives to congested roads. Limit: drainage still fails where drains are too few or poorly maintained.
6. Judgement: strategies succeed most where the state controls land and can fund infrastructure. They are weakest where informal growth outpaces planning. Success also varies within each city.

Quick self-test

1. State the difference between urbanisation and urban growth.
2. Give one city that is a world city but not a megacity.
3. Name the four stages of urban change in the more developed world listed in the specification.
4. Define a fortress development.
5. Why is the urban heat island usually strongest on calm, clear nights?
6. What is photochemical smog?
7. Give two environmental impacts of landfill.
8. What is Anopheles stephensi, and why does it matter for cities?
9. Name one non-communicable disease and one urban factor linked to it.
10. What does an ecological footprint measure?
11. What policy has Singapore used since 1989 to reduce ethnic segregation in public housing?
12. What two themes must the two contrasting case studies include?

Answers

1. Urbanisation is a rise in the proportion urban; urban growth is a rise in the number of urban dwellers.
2. Singapore.
3. Urbanisation, suburbanisation, counter-urbanisation and urban resurgence.
4. A gated, guarded development with controlled access.
5. Clear skies let heat radiate away from rural areas fast, while city surfaces release stored heat; calm air means the warm air is not mixed away.
6. Ground-level ozone pollution formed when sunlight acts on nitrogen oxides and hydrocarbons.
7. Two from: methane emissions, leachate entering groundwater, land take, odour and pests.
8. An invasive malaria mosquito that breeds in urban water containers; it can spread malaria in cities.
9. Asthma; traffic pollution near main roads, or damp housing.
10. The land and water area needed to supply a population’s resources and absorb its waste.
11. The Ethnic Integration Policy.
12. Patterns of economic and social wellbeing; the nature and impact of physical environmental conditions.

Where marks are usually lost

• Using “megacity” when the question asks about world cities, or treating the two as one idea.
• Listing the four stages of urban change without saying what drives each one.
• Describing new urban landscapes with no named example or no link to inequality or segregation.
• Saying the heat island peaks at midday, or forgetting the role of calm, clear conditions.
• Comparing incineration and landfill in general instead of in a specified urban area, as the specification requires.
• Treating malaria as purely rural and missing drainage, water storage and invasive urban vectors.
• Naming a broad group such as “cancer” rather than one specific non-communicable disease.
• Writing case studies as fact lists with no link to sustainability or residents’ experience and attitudes.
• Giving a final judgement that just repeats the question rather than weighing evidence.

Related resources

For the global flows behind world cities, see the global systems and governance guide and the globalisation practice questions. Unit 4 Section A is in the Changing places guide. Exam technique is in the 9635 exam preparation guide.

Official syllabus

These notes follow the OxfordAQA International AS and A-level Geography (9635) specification, Version 3.2, section 3.4.2 (Unit 4: Human geography 2, Section B). Check the current version on the OxfordAQA website.