The growth of megacities and social and environmental challenges from

this growth

Megacities • ‘Million cities’ are cities with over one million

people. • Megacities are urban areas with a population of

over 10m people. • In 1970 there were just three mega-cities, by 2020

there will be 30. • Have a look at the growth over time here .

What has caused megacities to grow? • Cities are growing as a result of two factors;

1. Natural increase (high birth, low death rates) 60%2. Rural Urban migration (30%)

• Other factor to think about is how land is being reclassification from rural to urban (10%)• In the ‘global village’ migration is now more

commonplace than ever. • Watch this video from 2.00 (Chapter 6) to see what

life is like for one migrant to Mumbai,

Push and Pull Factors • What can you think of?• Stick in the model …

Social Challenges • How many people in India are homeless? (video clip)• Governments can not provide housing for everyone.

Slums like Dharavi in Mumbai are common. • In developing countries, basic services like water and

energy are often provided by private companies and not by governments. These companies target wealthy areas and therefore the poor don’t get basic services e.g. water.• In developed world megacities, e.g. New York, the price

of accommodation is often unaffordable and therefore homelessness is also an issue, albeit on a smaller scale.

Environmental Challenges • Water pollution is high due to untreated sewage and air

pollution from industries is high too. HERE from 4.20• Air pollution is high. E.g. New Delhi was measured as the most

polluted city by the World Health Organisation as it has 153 micrograms of particles per cubic metre (compared to London’s 16) • In Delhi there will be 26m cars on the road by 2025. One way to

combat this is to restrict cars into the city centre according to their number plate (odd numbers one day and even the next) • Even in cities like Los Angeles, the smog that can remain over

the city due to anticyclonic weather conditions can create respirator problems for residents

Mumbai and Karachi• Mumbai• Kerachi• Make notes on these two cities focusing on why

they have grown as megacities from p187 in the text book.

Mumbai and Karachi• Social and environmental challenges of growth• http://www.global-migration.info/