Rate & Rise of Megacities (Edexcel IGCSE Geography)

Rate of Urbanisation

Factors Affecting the Rate of Urbanisation

• The main factors affecting the rate of urbanisation are:

  • Speed of economic development

    • Economic growth drives urbanisation

    • The faster the growth of secondary and tertiary employment sectors, the faster the growth of urbanisation

  • Rate of population growth

    • Economic growth needs a supply of labour

    • This demand can be met in two ways:

      • Natural increase in urban population - a slow way of meeting demand

      • Rural-urban migration - this is the more important source of labour as it attracts a wider pool of people into the urban region

Rise of Megacities

• Megacities are urban regions with over 10 million residents   

• In 2007, more people lived in an urban environment than a rural one

• By 2050 it is thought that more than two-thirds (7 billion) of the world population will live in urban areas

• This scaling up of the urban environment is the fastest in human history

• Largest growth of megacities is seen in Asia

Reasons for Growth

• Four main factors for growth:

  • Economic development

    • Encourages population growth which leads to the desirability of goods and services

    • All megacities act as service centres within the formal economic sector

    • However, megacities in developing and emerging countries are also important manufacturing centres (Mumbai in India or Dhaka in Bangladesh) with thousands working in the informal economy

  • Population growth

    • Young people are drawn to live in megacities with their vibrancy, fast pace and opportunities

    • There is also ‘internal growth’ where people who have moved into the cities have children, so sustaining population growth (Mexico City, Mumbai, Pearl River Delta in China)

  • Economies of scale

    • Cheaper to provide goods and services in one place than spread across several cities

    • Financial savings for local governments in respect of infrastructure provision

    • Communication and transport are centralised, making savings in time and money

  • Multiplier effect

    • As a city prospers, it acts as a beacon to people and businesses 

    • This encourages inward investment

    • This leads to yet more development and growth

    • Generating further need for skills and labour and job growth

    • This cycle multiplies the positive effects and growth continues (San Francisco and the digital development)

World Cities

• Megacities have a powerful attraction for people and businesses 

• They are influential cores with large peripheries

• World or global cities can be any size but exert particular influences around the globe

• They are considered prestigious, with status and power  

• They are critical hubs in the global economy

• The three top (alpha) world cities are London, New York, and Tokyo 

• These are the financial centres of the world, each with smaller networks of world cities feeding into them

• There are only four world cities in the southern hemisphere:  

  • Sydney

  • Rio de Janeiro

  • Sao Paulo

  • Buenos Aires