Year 12 Geography: Managing Challenges Facing a Megacity

Comprehensive review flashcards covering Year 12 Geography Unit 1 Topic 1 on megacities: population growth processes, spatial distributions, density and land use change, informal settlements and economies (Lagos, Shenzhen, Dharavi, Kibera), hazard vulnerabilities (Jakarta subsidence, São Paulo congestion and waste), wellbeing indicators (HDI), and stimulus analysis for extended responses (Dhaka).

Megacity (agglomeration)

Urban agglomeration with a population >10 million.

Urbanisation vs. Urban population growth

Urbanisation: inc. proportion of a country's population living in urban areas.
Urban population growth: Numerical inc. in people living in urban areas.

Demographic processes driving megacity expansion (2)

Natural increase: Birth rate exceeds death rate.
Rural-urban migration: Movement from rural to urban areas due to push and pull factors.

Pseudo-urbanisation

Urban growth without matching economic development, resulting in informal employment, housing shortages and expanding slums.

Physical water scarcity vs. Economic water scarcity

Physical water scarcity: Insufficient natural water resources to meet demand.
Economic water scarcity: Water exists, but poor infrastructure, governance or investment limits access.

Land tenure (and risks of insecure tenure)

Legal or customary right to occupy, use or manage land.
Insecure tenure: Risk of eviction, limited loan access, reduced housing investment.

WASH deficit & Infrastructure deficit

WASH: Water, sanitation and hygiene services needed to prevent disease.
Infrastructure deficit: Gap between required urban services (water, sewerage, energy, roads) and available infrastructure.

Human Development Index (HDI) and its limitations in megacities

HDI: Composite index (0-1) measuring life expectancy, education and GNI per capita.
Limitation: Hides intra-urban inequality and ignores environmental hazards.

Lagos, Nigeria: Primary drivers of rapid growth

Economic pull: Nigeria's financial/commercial hub, attracting migrants.
Demographic momentum: High natural increase from a youthful population.

Lagos vs. Shenzhen: Organic vs. Planned megacity expansion

Lagos: Organic, largely unplanned growth; informal settlements and infrastructure lag.
Shenzhen: Planned growth after 1980 SEZ designation; transformed into a manufacturing and technology hub.

Lagos vs. Tokyo: Developing vs. Developed megacity employment and housing

Lagos: High informal employment and widespread informal housing.
Tokyo: Formal economy, low informality, regulated housing and zoning.

Dharavi (Mumbai): Population density and informal economy

Spatial disparity: ~1 million residents at ~14× Mumbai's average density.
Informal economy: Generates >US$1 billion annually through recycling and manufacturing, despite hazardous conditions.

Kibera (Nairobi): WASH deficit and gendered safety implications

WASH deficit: Limited piped water, sanitation shortages, shared latrines and flying toilets.
Gendered risk: Unsafe sanitation increases assault risk and causes reduced fluid intake.

Jakarta, Indonesia: Causes and implications of land subsidence

Causes: Groundwater extraction, heavy building loads and low-lying delta location.
Implications: Increased tidal flooding and future submergence risk.

Karachi, Pakistan: The poverty–service access link

Inverse relationship: Higher poverty = lower piped water access.
Poor communities often rely on expensive informal water vendors.

São Paulo, Brazil: Spatial inequality and urban microclimates (Paraisópolis vs. Morumbi)

Paraisópolis favela borders affluent Morumbi.
Lack of green space and dense concrete make Paraisópolis 5-9°C hotter.

São Paulo, Brazil: Transport gridlock and waste-induced flooding

Traffic: High car ownership and highway-focused planning cause congestion and air pollution.
Flooding: Waste blocks drainage systems, increasing rainfall flooding.

What three dimensions and four indicators comprise the Human Development Index (HDI)? (H-E-I)

1. Long and healthy life → Life expectancy at birth (Health)
2. Knowledge → Mean years of schooling + Expected years of schooling (education)
3. Decent standard of living → GNI per capita (PPP$) (income)

Dhaka site vulnerability and informal expansion

Low-lying delta surrounded by four rivers.
Rapid urbanisation forces informal settlements into flood-prone areas.

Dhaka, Bangladesh: Slum settlement scale and epidemic water-borne disease (epidemiological impact)

Larger slums = poorer sanitation, with open and hanging latrines common.
Monsoon floods spread pathogens, increasing cholera and other water-borne diseases.