Centrifugal Population Movements (SL IB Geography)

Centrifugal movements

• Centrifugal movement refers to any movement outwards of the city centre, including:
  • Suburbanisation
  • Counter-urbanisation
  • Urban Sprawl
• There are several reasons for the movement of people away from urban areas:
  • High land prices
  • Congestion
  • Pollution
  • High crime rates
  • A lack of community
  • Declining services

Suburbanisation

• As towns grow, they expand outwards by a process known as suburbanisation
  • This growth adds to the built up area, but the building densities are generally lower than in the older parts of the town
  • The new suburbs are made up of mostly houses but also include places of employment and services

Causes of suburbanisation

• There are several causes of suburbanisation including:
  • Improved transportation makes movement between the suburbs and CBD easier
  • Larger homes and more space
  • Lower-cost housing
  • Lower crime rates
  • Improved environment, with lower pollution levels and more green space

Impacts of suburbanisation

• Urban settlements may continue to prosper and grow, people move out of the town or city altogether and commute to work:
  • The places they move to are called dormitory settlements because many residents only sleep there. 
  • They continue to have links with the town or city they have left
  • They still make use of urban services, shops, education, and healthcare in the city
• Urban sprawl 
• Wealth and business shift to the suburbs
• Social segregation as the wealthier population moves to the suburbs, leaving the less wealthy in the cities

Counter-urbanisation

• This is the movement of people from an urban area into the surrounding rural region. Causes include:
  • Mobility and accessibility: higher personal car ownership, increase in public transport and road development making easier access to rural areas
  • Increased wealth: making housing and travel more affordable
  • Agricultural decline (mechanisation and merger of farms): more land becomes available for housing and agricultural workers leave the area
  • Green belt: this prevents building in the area immediately around the urban area so people need to go further out to get the rural life they are looking for
  • Second homes and early retirement: have increased the movement of people from the city to the countryside

Urban sprawl

• Urban sprawl is the uncontrolled growth of the city into the surrounding rural areas and the expansion of population away from central urban areas into low-density rural-urban fringe
• There are several negative environmental, social and economic impacts, including:
  • Air pollution
  • Habitat loss
  • Traffic congestion
  • Social isolation