Trends and Patterns of Global Urbanisation: Distinction Between Two Terms and an Overview

trend is a change or development towards something new or different.

pattern is the repeated or regular way in which something happens or is done.It is an arrangement of lines or shapes, especially a design in which the same shape is repeated at regular intervals over a surface.

Global Trends of Urbanisation

More than half of the world’s population lives in urban areas. Due to the ongoing urbanisation and growth of the world’s population, there will be about 2.5 billion more people added to the urban population by 2050, mainly in Africa and Asia.Asian cities are growing very fast. Many are the fastest growing cities are found in the continent. In India , interestingly Tier II cities have a faster growing rate.The world’s urban areas are highly varied, but many cities and towns are facing problems such as a lack of jobs, homelessness and expanding squatter settlements, inadequate services and infrastructure, poor health and educational services and high levels of pollution.

In 1960, the global urban population was 34% of the total; however, by 2014 the urban population accounted for 54% of the total and continues to grow. By 2050 the proportion living in urban areas is expected to reach 66% (UNDESA, 2014). Figure 5.1 shows the change in the rural and urban populations of the world from 1950 through to projected figures up to the year 2050.

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 Urban and rural population of the world, 1950–2050. (UNDESA, 2014)

The process of urbanisation affects all sizes of settlements, so villages gradually grow to become small towns, smaller towns become larger towns, and large towns become cities. This trend has led to the growth of mega-cities. A mega-city is an urban area of greater than ten million people. Rapid expansion of city borders, driven by increases in population and infrastructure development, leads to the expansion of city borders that spread out and swallow up neighbouring urban areas to form mega-cities. In 1970, there were only three mega-cities across the globe, but by the year 2000, the number had risen to 17 and by 2030, 24 more mega-cities will be added .

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  The top mega-cities in the world in 1970, 2000 and 2030. (UNDESA, 2014

The global trend in urbanisation is not the same in all parts of the world. Asia and Africa currently have the highest rates of urbanisation. Figure 5.3 shows a comparison of trends in more or less developed regions of the world.

 

m2_ss5_fig5.3web

 Trends in urban population growth, comparing more and less developed regions. The graph shows the proportion of the total population living in urban areas.

Global Pattens of Urbanisation

The world passed a landmark statistic sometime in 2014, when it was estimated that for the first time in human history over 50% of the world’s population was living in urban areas. What is happening to where we live, and why?

For urbanisation to happen, people need to move into cities rather than be born in them. The end result is a growth in the size of urban spaces, which could also be called ‘built environments’.

Urban populations grow as a result of:

  • Rural-urban migration (voluntary): urban ‘Pull factors’ predominate as people anticipate an improved quality of life in a city together with enhanced future prospects for themselves and their family.
  • Rural-urban migration (forced): rural Push factors predominate as a result of environmental pressures in rural areas (floods/drought), food shortages and/or political conflict . More directly, government policy of moving rural inhabitants to cities may take any choice away from the migration. China’s bureaucratic relocation involved in the ‘National New-type Urbanisation Plan 2014-2020’ foresees moving over 260m people to cities in an attempt to modernise social and economic systems – an easier prospect when people are gathered rather than dispersed.
  • Assimilation: as urban areas expand they may incorporate nearby smaller towns and villages into expansive conurbations. The term ‘urban sprawl’ denotes the rapid spatial expansion of an urban area that is likely to surround and incorporate previously separate settlements.

Rapid suburbanisation took place as mass-housebuilding occurred in the decade after the Second World War. Rebuilding bomb-damaged cities and providing higher quality housing became a priority for the Labour government after 1945, and continued through successive governments. In order to prevent urban sprawl that had been a feature of the 1930s, much development was focused on the New Town programme (Milton Keynes, Telford etc.) and designating Green Belt land around major cities to, among other priorities, prevent cities merging into unbroken urban development.

 

Global patterns or urbanisation

North America, Europe and Oceania underwent their fastest urbanisation rates well before 1945 – in the 19th century. South and central America urbanised rapidly during the 1960s-80s, while the industrialisation and economic ‘take-off’ of many Asian countries in the 1980s to the present day (and continuing) has been accompanied by rapid urbanisation. This is likely to continue into the coming decades as economic growth continues and while there are still so many potential urban migrants living in rural areas. The continent that is presently starting to see rapid urbanisation occurring is Africa, with cities such as: Dar es Salaam (Tanzania) due to grow by 85% between 2010-2025; Nairobi (Kenya, 77%); Kinshasa (DRC, 72%) and the continent’s largest city – Lagos (Nigeria, 50%).

Emergence of megacities, world cities and their role in global and regional economies

Megacities:

  • Megacities are defined by their size (over 10m inhabitants) rather than their global significance. It may be one city (metropolitan area) such as Cairo, Egypt or a merging of a number of cities into a continuous built-up area (Tokyo-Yokohama, Japan).
  • They have doubled over the past two decades, from 14 in 1995 to 29 in 2016.
  • Their development is more likely where rapid economic growth is concentrated in a limited number of locations within a country. Mass rural-urban migration tends to be focused on these core urban areas rather than dispersed between a wider set of optional cities that migrants may select from, with different decisions made.
  • Megacities can benefit from more efficient infrastructure, such as mass transport systems and economically with both horizontal and vertical industrial integration. However, urban problems may be magnified in megacities (congestion, waste disposal, air pollution, lack of housing) and prove more problematic to solve.
  • Megacities are frequently major global hubs of manufacturing and export (Shenzhen, China and Delhi, India) in which goods are produced efficiently and at low cost and exported to the major world markets. They are also key markets, themselves for basic raw materials, components and energy resources.

Can developing countries create mega cities that are fit to live in? If you want to know more, you can check this video via AJ+ that explains The Megacities of 2050

World cities:

  • These are cities that have particular influence on global economic, cultural and political systems. They may be megacities (New York, Tokyo) but aren’t necessarily (London, Moscow, Paris, Berlin). They are seen to function as global hubs.
  • Key global financial networks are influenced by their concentration of major banks and commercial HQs, stock markets and politico-economic influence and include New York, London and Tokyo. Decisions taken there have global significance.
  • World cities may display the full range of key influences, or be distinctive for their dominance in certain ones rather than others (Paris: culture, fashion, art and media).

Many of the fastest developing cities in Asia combine a number of economic functions but are dominated by the service economy. Hyderabad, in India, is fast becoming an economic hub dominating the tertiary and quaternary sector in India. As well as being the financial and economic capital of the state of Telangana it is experiencing rapid growth as a city of Information Technology. Its call centres employ many university graduates who are in surplus to jobs available, the highest qualified of whom have led to it hosting major firms such as IBM, Dell, Oracle and General Electric. The city is aiming to become they key location for the Microsoft Development Centre in India and a prestige township development- HITEC City – has attracted a number of start-up IT and IT Enabled Services (ITES) allowing remote working.

Source(s):

Open.Edu

Tutor2U

Problems of Cities

Impact of Migration on Cities

 

 

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Why Cities Grow So Fast?

Urbanism is the new way of life. Our world is turning into a big urban realm. The first urban settlements are thought to have started around 3500 BC in lower Mesopotamia  around the Tigris and Euphrates. First was Ur, which from 2300 BC to 2180 BC was the capital city of the Sumerian Kingdom, extending north along the Fertile Crescent, possibly as far as the Mediterranean. Diversification of economy led to growth of cities.

Since then cities continue to grow because people believe that the benefits of urban life outweigh the liabilities associated with living in a densely populated place. Cities grow so fast because they are efficient. They grow layer by layer. Clearly, the primary benefit of clustering populations is the efficiencies gained by serving a large economic market concentrated in a relatively small area. When businesses serve large numbers of people clustered in a relatively small area, they are able to achieve advantageous economies of scale. They also get benefit of agglomeration. In Contrast, when businesses must accommodate a much larger service area in order to achieve a minimum demand threshold, they incur greater operational transportation costs.

In addition to making it easier to achieve positive economies of scales, urban areas provide markets that are large enough to encourage and justify specialization. Generally, the level of specialization in an area is a function of the size of the market.

For cities to function, they must have internal and external linkages (streets, roads, docks, highways, telephone and internet service, and public transportation facilities) that allow for an efficient flow of goods, services, and information. Internal infrastructure of city and road design play an important role in safety in city. Normally larger cities accommodate larger complexes of specialized activities. Sometimes, cities grow at a rate that overwhelms their transportation/communication systems. In such circumstances, city officials must dedicate resources to improving connectivity and accessibility or accept the limits imposed by an obsolete circulation system. This is often a particularly vexing problem in older large urban centers such as London or Amsterdam where ancient transportation networks and infrastructure cannot efficiently handle the demands of growing populations and markets. Therefore, the more efficient the communication system, the more likely it is that an urban area will grow.

The layout of cities evolved development of transport. The land-use of the city change with changing layout.It changed with the changing mode of transport.

Despite the capability of cyber-space technology to reduce the importance of distance, it is still necessary for people to travel to urban centers for extremely specialized products and services. City layout is often a result of distribution of services and availability of goods as evident by city layout theories such as Concentric Zone Model of Burgess. Von Thunen based his model on transportation cost. The city can develop around many nuclei as shown in multiple nuclei model.Many who live in relatively isolated places are able to make on-line purchases that bring most of the necessities of life to their doorsteps, in order to undergo major surgery, they normally must travel to an urban medical center. Additionally, although airline tickets can now be purchased online, travelers must go to a central airport to catch a flight. Of course these are only two examples of the many essential functions of urban places. Therefore, distance still matters.

Furthermore, even though people can order much of what they need by telephone or by way of the internet, resources, labor, capital and management must come together in order to manufacture, package, and process consumer products.

One aspect is of city coming to villages by diversification, by sprawl or more naturally by urban expansion.Today the possibility of the migrant’s return to the old village should be whole heartedly discouraged . No one should be allowed to live a life that is an annual contribution to the national statistics on starvation, infant mortality, disease , and suicide. But the possibility of never leaving a village that is transforming into a new town raises the prospects of a better life. It is a task wholly imaginative and without the prescription of tested models. Cities designed explicitly for the rural areas is not just a good idea for the poor, but can act as a game changer for the self-centered ugliness created in the metros by the middle-class.

 

Source(s):

E Education 

Wikipedia

 

 

 

 

 

 

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Democracy Is Losing the World – LewRockwell

MCViewPoint

We are an unserious nation, engaged in trivial pursuits, in a deadly serious world.

https://www.lewrockwell.com/2018/12/patrick-j-buchanan/how-democracy-is-losing-the-world/

By Patrick J. Buchanan

If Donald Trump told Michael Cohen to pay hush money to Stormy Daniels about a one-night stand a decade ago, that, says Jerome Nadler, incoming chair of House Judiciary, would be an “impeachable offense.”

This tells you what social media, cable TV and the great herd of talking heads will be consumed with for the next two years — the peccadillos and misdeeds of Trump, almost all of which occurred before being chosen as president of the United States…

Does the world still envy us our free press, which it sees tirelessly digging up dirt on political figures and flaying them with abandon?

Among the reasons democracy is in discredit and retreat worldwide is that its exemplar and champion, the USA, is beginning to resemble France’s Third Republic in its last…

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Concept of Traffic Flow Diagram

Traffic flow is the study of interactions between travelers (including pedestrians, cyclists, drivers, and their vehicles) and infrastructure (including highways, signage, and traffic control devices), with the aim of understanding and developing an optimal transport network with efficient movement of traffic and minimal traffic congestion problems.

Attempts to produce a mathematical theory of traffic flow date back to the 1920s, when Frank Knight first produced an analysis of traffic equilibrium, which was refined into Wardrop’s first and second principles of equilibrium in 1952.The fundamental diagram of traffic flow is a diagram that gives a relation between the traffic flux (vehicles/hour) and the traffic density (vehicles/km). A macroscopic traffic model involving traffic flux, traffic density and velocity forms the basis of the fundamental diagram. It can be used to predict the capability of a road system, or its behaviour when applying inflow regulation or speed limits.

Basic Premises

  • There is a connection between traffic density and vehicle velocity: The more vehicles are on a road, the slower their velocity will be.
  • To prevent congestion and to keep traffic flow stable, the number of vehicles entering the control zone has to be smaller or equal to the number of vehicles leaving the zone in the same time.
  • At a critical traffic density and a corresponding critical velocity the state of flow will change from stable to unstable.
  • If one of the vehicles brakes in unstable flow regime the flow will collapse.
    The primary tool for graphically displaying information in the study traffic flow is the fundamental diagram. Fundamental diagrams consist of three different graphs: flow-density, speed-flow, and speed-density. The graphs are two dimensional graphs. All the graphs are related by the equation “flow = speed * density”; this equation is the essential equation in traffic flow. The fundamental diagrams were derived by the plotting of field data points and giving these data points a best fit curve. With the fundamental diagrams researchers can explore the relationship between speed, flow, and density of traffic.

Speed-density

New Picture

Speed Density Diagram

The speed-density relationship is linear with a negative slope; therefore, as the density increases the speed of the roadway decreases. The line crosses the speed axis, y, at the free flow speed, and the line crosses the density axis, x, at the jam density. Here the speed approaches free flow speed as the density approaches zero. As the density increases, the speed of the vehicles on the roadway decreases. The speed reaches approximately zero when the density equals the jam density.

Flow-density
In the study of traffic flow theory, the flow-density diagram is used to determine the traffic state of a roadway.

New Picture

Flow Density Curve

Currently, there are two types of flow density graphs. The first is the parabolic shaped flow-density curve, and the second is the triangular shaped flow-density curve. Academia views the triangular shaped flow-density curve as more the accurate representation of real world events. The triangular shaped curve consists of two vectors. The first vector is the free flow side of the curve. This vector is created by placing the free flow velocity vector of a roadway at the origin of the flow-density graph. The second vector is the congested branch, which is created by placing the vector of the shock wave speed at zero flo

w and jam density. The congested branch has a negative slope, which implies that the higher the density on the congested branch the lower the flow; therefore, even thoug

h there are more cars on the road, the number of cars passing a single point is less than if there were fewer cars on the road. The intersection of free flow and congested vectors is the apex of the curve and is considered the capacity of the roadway, which is the traffic condition at which the maximum number of vehicles can pass by a point in a given time period. The flow and capacity at which this point occurs is the optimum flow and optimum density, respectively. The flow density diagram is used to give the traffic condition of a roadway. With the traffic conditions, time-space diagrams can be created to give travel time, delay, and queue lengths of a road segment.

New PictureSpeed-flow
Speed – flow diagrams are to determine the speed at which the optimum flow occurs. There are currently two shapes of the speed-flow curve. The speed-flow curve also consists of two branches, the free flow and congested branches.

 

Source(s):

Wikipedia

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