Every week 3 million people are added to cities of developing world according to UN-HABITAT’s new report State of the World’s Cities 2008/9: Harmonious Cities. Globally urbanization levels will rise dramatically in the next 40 years to reach 70 percent by 2050.

Though more than 70 per cent of the populations of Europe, North America and Latin America are already urban, Asia and Africa which are predominately rural, with 41 per cent and 39 per cent of their populations living in urban areas, respectively, are in for a major demographic shift.

By the middle of the 21st century, the total urban populations of the developing world will more than double, increasing from 2.3 billion in 2005 to 5.3 billion in 2050.

Asia is urbanizing rapidly, with approximately 41 per cent of its inhabitants now living in cities. By 2050, Asia will host 63 per cent of the global urban population, or 3.3 billion people. In Asia, the urban transition will occur even earlier than Africa, owing to rapid urban growth rates in China, a country that is expected to be 70 per cent urban by 2050. Urban growth rates in India will be slower; by 2050, 55 per cent of its population, or 900 million people, will live in cities.

According to the report, the rate of change of the urban population in Africa is the highest in the world. If current trends continue, by 2050 half of Africa’s population will be urban. With 1.2 billion people living in cities and towns, African cities will soon host nearly a quarter of the world’s urban population.

Concerned about the implications of this dramatic change in human history, in his foreword, Ban Ki-moon, Secretary-General of the United Nations, points out that though cities embody some of societies most pressing challenges, from pollution and disease to unemployment and lack of adequate shelter, they also present real opportunities. He then calls for city authorities to advance the prosperity of their inhabitants while achieving equitable social outcomes and sustainable use of resources.

Growing Cities
In planning for harmonious cities, the report highlights some of the significant changes in the exponential growth of cities around the world. According to the report the main cause of urban growth in most countries is natural increase - when births in cities outpace deaths. In countries with low levels of urbanization, migration is often the primary engine driving city growth, as is the case in various countries in Africa and Asia. In many countries, the largest movements of population are taking place between cities and not from rural to urban areas.

In analyzing city level growth around the world, the report finds that some of the fastest growing cities in the world are in China, where growth rates can be higher than 10 per cent per year; this includes the cities of Chongqing, Xiamen and Shenzhen. This rapid shift has been brought about by the adoption of a pro-urban approach to economic development by the government of China.

In the case of Africa, the report notes that the capitals and primary cities on the continent have the highest growth rate. For example, Niamey, Niger; Dar es Salaam, Tanzania; and Lomé, Togo, all grew at an annual rate of 4 per cent or more, while Kigali, the capital of Rwanda, experienced a soaring annual population growth of 8.6 per cent from 2000 to 2005. The authors of the report caution that such urban primacy and concentration of a significant proportion of the national urban population in one city could be bad for business - it distorts the economy, creates imbalances in the distribution of populations and resources and gives rise to different forms of socio-economic disarticulation.

Shrinking Cities
An interesting new departure highlighted by the report is the phenomenon of shrinking societies and cities. The populations of 46 countries, including Germany, Italy, Japan, most of the former Soviet states, and several small island states, are expected to be smaller in 2050 than they are now. These demographic trends are reflected at the city level, as well. In the last 30 years, more cities in the developed world shrank than grew.

Negative growth trends are largely associated with cities in North America and Europe, where the number of shrinking cities has increased faster in the last 50 years than the number of expanding cities. In the United States alone, 39 cities have endured population loss. In the United Kingdom, Germany and Italy, 49, 48 and 34 cities, respectively, shrank in size between 1990 and 2000. A number of cities in countries of the former Soviet bloc are losing their populations. Nearly 100 Russian cities experienced negative growth in the 1990s; in Ukraine, 40 cities experienced population loss.

In the case of cities in the developed world, the report notes that on average, 2.3 million people migrate into developed countries each year. This means that migration - both legal and illegal - accounts for approximately one-third of the urban growth in the developed world. Without migration, the urban population of the developed world would likely decline or remain the same in the coming decades.

Surprisingly enough shrinking cities are not just a problem of developing countries. UN-HABITAT’s analysis of urban growth in Africa from 1990 to 2000 reveals 11 cities that experienced declining populations, of which 10 were small cities. The authors argue that it is possible that some cities lost populations as a result of war, disasters or civil conflicts, but in most cases, population loss has been a transitory process. Recent studies on migration and urbanization in Africa have produced empirical evidence demonstrating new patterns of return migration from urban to rural areas that may have an impact on population decline in the future.

The report provides a useful Compendium of information on what is clearly one of the most pressing challenges pertaining to global sustainability and environmental well being. It is available for download in whole or in part.

Further information and links to the report

Source: UN-HABITAT