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

This guide covers section 3.4.2, People and contemporary urban environments, of the OxfordAQA International AS and A-level Geography (9635) specification, Version 3.2. The specification places this content in Unit 4: Human geography 2, Section B. Unit 4 is a 1 hour 30 minute written exam with two sections of 40 marks each, and you answer all questions.

Use it with the revision notes and the practice questions. For the full course, see the OxfordAQA A-level Geography hub and the 9635 checklist.

Coverage table

Syllabus reference	What you must know or be able to do (from the specification)	Where assessed
3.4.2.1 Urbanisation	Importance of urbanisation; global patterns since 1945; megacities and world cities and their economic role; processes of urban growth; change in the more developed and developing world	Unit 4, Section B
3.4.2.2 Urban forms	Megacity and world city characteristics; physical and human factors in urban form; land use, inequality, segregation and diversity; new urban landscapes; the post-modern city	Unit 4, Section B
3.4.2.3 Social and economic issues	Issues of inequality, segregation and cultural diversity; strategies to manage them	Unit 4, Section B
3.4.2.4 Urban climate	Impact of urban forms on local climate: heat island, precipitation, fog and thunderstorms, wind, air quality; pollution reduction policies	Unit 4, Section B
3.4.2.5 Urban waste	Sources and waste streams; impacts of disposal methods; incineration versus landfill in a specified urban area	Unit 4, Section B
3.4.2.6 Health and wellbeing	Patterns of health, mortality and morbidity; environment, air and water quality, urban stress and disease; malaria; one named non-communicable disease	Unit 4, Section B
3.4.2.7 Other environmental issues	Atmospheric and water pollution, drainage, dereliction; management strategies	Unit 4, Section B
3.4.2.8 Sustainable urban development	Local and global impacts; ecological footprint; dimensions of sustainability; features of sustainable cities; liveability; opportunities, challenges and strategies	Unit 4, Section B
3.4.2.9 Case studies	Two contrasting urban areas: economic and social wellbeing, physical environmental conditions	Unit 4, Section B

3.4.2.1 Urbanisation

Urbanisation is the rise in the share of a population living in urban areas. Urban growth is the rise in the absolute number of urban dwellers. A country can show urban growth with little urbanisation if rural numbers rise just as fast.

The UN’s World Urbanization Prospects 2018 estimated that 30% of the world’s people were urban in 1950 and 55% in 2018, with 68% projected for 2050. It counted 33 cities of more than 10 million people in 2018. Most recent growth is in Asia and Africa.

Megacity: an urban area of more than 10 million people. World city: a city with a major command role in the global economy (finance, corporate headquarters, media, culture). The two overlap but differ. Lagos is a megacity with a smaller global command role than its size suggests; Singapore has far fewer than 10 million people but is a world city for finance, shipping and regional headquarters.

Processes driving growth. Economic: jobs and wages pull migrants. Social: schools and health care. Technological: transport and farm mechanisation that releases rural labour. Political: capital-city status, state investment, conflict. Demographic: natural increase among young urban populations.

More developed world. Deindustrialisation (loss of manufacturing) and decentralisation (jobs and retail moving to the edge) hollowed out many inner cities. The service economy replaced factory work. Cities passed through urbanisation, suburbanisation, counter-urbanisation (moves to small towns and rural areas) and urban resurgence (inner-area regrowth).

Developing world. Rural to urban migration feeds rapid growth. Modern high-tech core areas (business districts, technology parks) sit beside a large informal sector: unregistered, untaxed work such as street trading and recycling.

Evaluation: the four-stage sequence fits many UK and US cities but is not universal. Some cities in the developing world show suburbanisation of the rich and rural-urban migration of the poor at the same time.

Worked paragraph. “Urban growth in the developing world is driven mainly by economic processes.” Discuss. – “Economic pull is strong: a migrant can earn more in a city’s informal sector than in farming [knowledge]. In Lagos, the size of street trading and waste-picking shows how many newcomers find work outside the formal economy [application]. Yet natural increase among young adults now adds a large share of urban growth in many African cities, so migration is only part of the picture [analysis]. Economic pull starts the process; demographic momentum then sustains it [evaluation].”

3.4.2.2 Urban forms

Urban form is shaped by physical factors (relief, coasts, rivers, flood risk) and human factors (land values, transport, planning, colonial history, wealth). Land use, economic inequality, social segregation and cultural diversity all show spatial patterns.

New urban landscapes:

• Town centre mixed developments: retail, offices, homes and leisure in one scheme.
• Cultural and heritage quarters: districts rebranded around arts, history or nightlife.
• Fortress developments: gated, guarded spaces with controlled access.
• Gentrified areas: older working-class districts renovated by higher-income newcomers. The sociologist Ruth Glass coined “gentrification” in 1964, writing about London.
• Edge cities: office and retail centres on the urban fringe. The journalist Joel Garreau popularised the term in his 1991 book Edge City: Life on the New Frontier.

The post-modern city is fragmented rather than organised around one centre. It has many centres, sharp contrasts between rich enclaves and poor districts, private and surveilled spaces, and buildings designed for image and consumption.

Example: Eko Atlantic, Lagos. This private city is being built on about 9 km² of land reclaimed from the sea in front of Bar Beach, beside Victoria Island. An 8.5 km sea barrier protects it. It shows fortress and post-modern traits: a protected high-income enclave in a city where many live in informal housing. Nearby residents link the works to coastal erosion and surges; the state was criticised for not involving local people.

Evaluation: the post-modern model describes fragmentation well but explains less.

3.4.2.3 Social and economic issues

Economic inequality shows in income, housing and services. Social segregation separates groups by income, ethnicity or religion. Cultural diversity enriches a city but can cause tension over housing and jobs.

Strategies: housing policy, upgrading of informal settlements, transport links to jobs, anti-discrimination law, community programmes and mixed-tenure housing.

Singapore case. The Housing and Development Board (HDB) was formed in 1960. Close to 80% of residents now live in public housing. Since 1989 the Ethnic Integration Policy has set ethnic quotas for each HDB block and neighbourhood so that no group dominates one area. Supporters say it prevents enclaves. Critics argue that quotas limit sellers’ choice of buyers and that mixed housing alone does not remove prejudice.

Lagos case. Makoko is an informal settlement on and beside Lagos Lagoon, with many homes on stilts and fishing as a main livelihood. In July 2012 demolitions on 72 hours’ notice left nearly 3,000 people homeless. The state cited environment and safety; campaigners saw displacement of the poor from valuable waterfront.

Evaluation: top-down strategies can work where the state controls land and housing, as in Singapore. They are harder to copy where most housing is informal and land is contested.

3.4.2.4 Urban climate

• Urban heat island (UHI): cities are warmer than surrounding rural areas, most clearly on calm, clear nights. Causes: dark surfaces store heat and release it at night; sealed surfaces reduce evaporation; vehicles and air-conditioning add waste heat; tall buildings trap outgoing radiation.
• Precipitation: rising warm air and extra condensation nuclei (dust, particulates) can raise the frequency and intensity of convectional rain downwind of a city.
• Fog and thunderstorms: more nuclei favour fog. Strong afternoon heating favours summer thunderstorms.
• Wind: rough surfaces cut average wind speed, but canyon effects funnel and accelerate wind between tall blocks, and tall buildings cause gusts and eddies.
• Air quality: particulates (PM10, PM2.5) from traffic, industry, generators and burning; photochemical smog forms when sunlight acts on nitrogen oxides and hydrocarbons to produce ground-level ozone.

Pollution reduction policies. Singapore introduced Electronic Road Pricing on 1 April 1998, charging vehicles to use busy roads at busy times. London’s Ultra Low Emission Zone began in 2019 and covered all London boroughs from August 2023. Lagos opened bus rapid transit in 2008 and its Blue Line urban railway to passengers in 2023.

Evaluation: charges shift behaviour but hit lower-income drivers hardest, and need good public transport.

3.4.2.5 Urban waste and its disposal

Sources: industrial and commercial activity, construction, and personal consumption. Waste streams (food, paper, plastics, glass, metals, e-waste) reflect economic characteristics, lifestyles and attitudes. Richer households produce more waste per person, with more packaging and paper. Poorer households produce less, with a higher organic share.

Disposal approaches and environmental impacts: unregulated dumping (leachate, open burning, disease vectors); recycling (saves materials but needs sorting and markets); recovery (energy from waste, composting); incineration (cuts volume, risks air pollution and toxic ash); burial in landfill (methane, leachate, land take); submergence (dumping at sea); and trade (export of waste, often to poorer countries).

Comparison in a specified urban area (Singapore and Lagos). Singapore has very little land. Its National Environment Agency states that incineration reduces waste by up to 90% and recovers energy that meets up to 3% of the island’s electricity needs. Ash and non-incinerable waste go by covered barge to Semakau Landfill, an offshore site created by a 7 km rock bund enclosing sea between two islands. It began operating in 1999. Its space is finite, driving recycling policy.

Lagos relies on landfill. Olusosun, about 40 hectares, receives up to 10,000 tonnes a day. Once on the city’s edge, it is now surrounded by homes and businesses. Waste burning there pollutes the air, and leachate contaminates groundwater.

Evaluation: incineration suits land-scarce, wealthy cities that can afford emission controls. Landfill is cheaper but its costs fall on nearby, often poorer, residents. Neither method reduces the waste produced in the first place.

3.4.2.6 Urban environments, health and wellbeing

Health, mortality and morbidity vary within cities. They tend to be worse in poorer, crowded, polluted districts. Links to study: climate and topography (poorly drained, low-lying land); air quality (respiratory disease); water quality (diarrhoeal disease where sanitation is poor); and the stresses of urban living (noise, crowding, long commutes).

Malaria is spread by the bites of infected female Anopheles mosquitoes. WHO reports that its African Region had about 95% of malaria cases and deaths in 2024. Transmission rises in wet seasons as standing water multiplies breeding sites. Urban risk peaks in low-lying, poorly drained informal districts and where water is stored in open containers. A changing threat is Anopheles stephensi, a mosquito native to South Asia and the Arabian Peninsula. It was found in Djibouti around 2012, and WHO notes it thrives in urban settings and breeds in artificial containers and water tanks. WHO recommends insecticide-treated nets and indoor residual spraying as core vector control. Cities add drainage, covered water stores and early diagnosis. Singapore was certified malaria-free by WHO in 1982.

Named non-communicable disease: asthma. Asthma is a long-term inflammatory condition of the airways. Within cities, attacks are linked to traffic pollution (nitrogen dioxide, particulates) near main roads, and to damp, mouldy housing. Both are more common in deprived inner areas. Lifestyle factors such as smoking in the home add to risk. Impacts include missed school and work and emergency admissions. Management includes clean-air zones, better housing and access to diagnosis and care.

Evaluation: patterns show association, not proof of cause. Poorer districts face several risks at once, so separating the effect of one variable is difficult.

3.4.2.7 Other contemporary urban environmental issues

• Atmospheric pollution: see 3.4.2.4.
• Water pollution: untreated sewage, industrial discharge and surface run-off. In Makoko, homes sit over a lagoon with little formal sanitation.
• Urban drainage: impermeable surfaces shorten lag time and raise peak discharge. Low-lying Lagos floods often, linked to unplanned growth and too few, poorly maintained drains. Strategies include sustainable urban drainage systems (SuDS): permeable paving, swales, retention ponds and green roofs.
• Dereliction: abandoned land and buildings after deindustrialisation. Strategies include brownfield regeneration and temporary green space.

3.4.2.8 Sustainable urban developments

Cities draw resources from far beyond their boundaries. The ecological footprint, developed by Mathis Wackernagel and William Rees (book published 1996), measures the land and water area needed to supply a population and absorb its waste, in global hectares. Large, wealthy cities have footprints many times their own area.

Dimensions of sustainability: natural (ecosystems, resources), physical (buildings, infrastructure), social (equity, community, health) and economic (jobs, investment). Sustainable cities offer efficient public transport, compact mixed land use, renewable energy, low waste and green space. Liveability is the quality of life a city offers: safety, health care, housing, environment, culture.

Opportunities: density makes public transport efficient and concentrates innovation. Challenges: rapid informal growth, weak governance and unequal liveability.

Evaluation: liveability rankings often reflect the needs of high-income expatriates, not low-income residents.

3.4.2.9 Case studies

The specification requires two contrasting urban areas. They must cover patterns of economic and social wellbeing and the nature and impact of physical environmental conditions. Link both to environmental sustainability, the character of each place and the experience and attitudes of its people. Lagos and Singapore work as a contrasting pair:

Theme	Lagos	Singapore
Wellbeing	Large informal sector; wealth in Victoria Island and Eko Atlantic beside Makoko	Most residents in public housing; ethnic quotas since 1989
Physical conditions	Low-lying lagoon and coast; flooding and erosion	Tropical island with very little land; heat
Waste	Landfill at Olusosun	Incineration and offshore Semakau Landfill
Health	Malaria still transmitted (high risk across Nigeria)	Malaria-free since 1982
Experience and attitudes	Residents contest evictions and coastal works	Broad acceptance of state planning, with debate over quotas

Your teacher may choose different case studies; the specification does not name them.

Common errors

• Treating “megacity” and “world city” as the same thing.
• Calling every gated estate “post-modern” without explaining fragmentation.
• Saying the urban heat island is strongest at midday. It is usually clearest at night.
• Describing incineration and landfill in general when the specification asks for a comparison in a specified urban area.
• Writing about malaria as a rural disease only and ignoring urban breeding sites.
• Naming “cancer” or “lung disease” rather than one specific non-communicable disease.
• Presenting a case study as description with no link to sustainability or residents’ experience.

Where to go next

For world cities and global flows, see the global systems and governance guide and globalisation revision notes. Unit 4 Section A is in the Changing places guide. For data skills, use the fieldwork skills guide; for technique, the exam preparation guide.

Official syllabus

This guide follows 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.