Johannesburg has come second in a study of the vulnerability of major cities in Africa, Asia Pacific and the Middle East to environmental degradation and disaster.

IN a study of major cities in the Asia Pacific, the Middle East and Africa, Johannesburg is ranked as the second least vulnerable to urbanisation and the environment.

This is according to the Worldwide Centres of Commerce Index, set up after the United Nations Population Fund concluded that in 2006 the world's urban population exceeded its rural population, making 2007 the first year in which humans existed as an "urban species".

Joburg was included as one of 21 cities in Asia Pacific, the Middle East and Africa that ranked in the top 50 of the world's centres of commerce.

In 2007, the MasterCard Worldwide Urbanization and Environmental Challenges Report launched its first Worldwide Centres of Commerce Index. The report ranked leading global cities, providing the first assessment ever of how these cities contributed to global commerce.

The report looked at the vulnerability of the 21 cities and key environmental factors like air and water pollution that directly affected the quality of life in those cities, and the risks to the health and safety of their residents. Sustainability of a city's growth is closely linked to how that city maintains its environment.

"With urbanisation and urban living comes a new challenge, that of protecting and improving the urban environment. Nowhere is this more acute and pressing than across the Asia Pacific, Middle East and Africa regions," says the report.

One is the highest score; Melbourne in Australia, with a score of 2.03, ranks top; Johannesburg comes in second with 2.37; Singapore is ranked third with 2.40; and at the bottom of the ranking is Mumbai in India, with a score of 7.78.

The author of the report, Yuwa Hedrick-Wong, is quoted by news agency I-Net Bridge as saying that the overall picture for Johannesburg is that "by and large the city has done exceptionally well in creating a high quality environment within its urban setting, managing increasing population growth and a degree of unpredictable environmental impacts to ensure a good quality of life for residents".

He cautions, though, that unpredictability means the city should not become complacent.

The assessment took three dimensions into consideration: environmental indicators that are largely government controlled; environmental indicators that are affected by climate change and are indirectly government controlled; and indicators of "environmental risks".

Dimension one
Water potability, water availability, sewage system, waste removal, air quality and infectious diseases were the conditions taken into consideration in dimension one. This was considered the most important ranking. Joburg is ranked sixth on this dimension.

Cities that rank lowest in environmental quality suffer from very high levels of air pollution, particularly emissions from vehicles, poor waste and sewage removal and coverage, and high instances of infectious diseases.

Cities like New Delhi, Mumbai, Jakarta and Beijing score badly on potability. In Beirut's case degraded environmental services are caused by political turbulence.

Dimension two
Indicators in this dimension were not directly considered to be under government control and were largely subject to the effects of climate change. They included the rise of sea level, water scarcity due to drought, severe storms and fires. Joburg ranks fourth in dimension two.

"The impact of climate change is likely to be especially marked in Bangkok, Jakarta, Shanghai and Sydney due to flooding from a rise in sea level; [it] may be less marked in Singapore, Tokyo and Melbourne, where adaptive strategies may be easier to implement," the report indicates.

Dimension three
Indicators here were those considered to be "highly unpredictable", with an immediate effect on the cities' environment. They included earthquakes, typhoons, hurricanes and volcanic eruptions.

Johannesburg ranks the second lowest in terms of risk of these factors influencing the city and its residents.

Richer cities, with more disposable income and better educated people to manage the city, are likely to score higher. This applies too to "emerging" cities like Johannesburg, Seoul and Kuala Lumpur, says the report.

It would appear that not having been built on a major river or positioned as a port city has placed Joburg in an advantageous position. Often large industries dump their waste into rivers or the sea, making these cities vulnerable to the effects of that pollution. Joburg is also not vulnerable to natural events like hurricanes, earthquakes or volcanic eruptions.

Hedrick-Wong says that Joburg's "overall ranking of second place reflects the city's geographic location which is well protected from most adverse environmental factors that are either outside of the government's control or highly unpredictable, with one notable exception - drought".

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