If developing countries do not improve the quality and diversity of transportation, their greenhouse gas emissions will exceed the industrialised world's, adding to economic, health, and environmental problems associated with global warming, says a new report.

The rapid increase in car and truck use in developing countries has been the main reason for the increase in transportation-related emissions in Africa, Asia and Latin America, says the Pew Centre on Global Climate Change.

Some time after 2010, these regions could outstrip the industrial world in emitting greenhouse gases, which scientists blame for climate change.

If current trends continue, the number of motor vehicles in use worldwide will double in the next 20 to 30 years, with much of the increase occurring in developing nations, the Washington think tank says in a new report, ' Transportation in Developing Countries: An Overview of Greenhouse Reduction Strategies .'

"If current motorisation patterns prevail, there will be another 700 million vehicles globally over the next two to three decades," says centre President Eileen Claussen.

According to her organisation's report, transportation-related carbon dioxide emissions grew in developing countries by an average of four percent each year between 1980 and 1998. In Asia, where there was a much more rapid increase in motor vehicle use, such emissions grew at an annual rate of 5.6 percent.

Carbon dioxide and other heat-trapping greenhouse gases — caused by the burning of fossil fuels like oil, gas and coal — have been blamed for heating the oceans, fracturing polar ice shelves, and fuelling more intense El Nino weather patterns.

Using case studies conducted with experts in Chile, China, India and South Africa, the Pew Centre estimates high and low projections of transportation-related greenhouse gas emissions in 2020 compared to 2000.

Growth unavoidable

Rapid growth in transportation-related emissions is unavoidable in most developing countries, it says.

According to the low projections, only South Africa shows a possible decrease in emissions — 12 percent — mostly due to anticipated population declines and shifts away from carbon-intensive synthetic fuels.

Emissions in Shanghai, China, will possibly quadruple, according to the low estimates, because of strong projected economic growth, urban decentralisation, and rapid increases in car ownership.

The high scenarios range from an 82 percent increase in South Africa to a sevenfold increase in Shanghai.

The report acknowledges that enhanced mobility has many positive effects on economic development and social welfare, including more efficient movement of goods and improved access to jobs, health services and education.

If greater mobility, however, is achieved primarily through increased reliance on conventional private cars, it can mean diverting substantial financial resources to roads which will worsen air pollution and traffic congestion.

"The benefits (of increased mobility) are enormous," says the report, "but the costs can be substantial."

Climate friendly

The key to solving the transportation problems is to make sure that nations "develop transportation systems that are climate-friendly at the same time that they meet the needs of the people who use them," says Claussen.

The report acknowledges that in the developing world, economic and social development — not climate change — drive the decision making of transportation policy makers.

But it says many of the strategies that could reduce greenhouse gas emissions would also address the immediate problems of local air pollution, safety, access to basic transportation and infrastructure financing pressures.

The report identifies several transportation options, including improved motor vehicle technology to promoting mass transit and car sharing, that could address high-priority local issues while keeping emissions growth to a minimum.

Shanghai model

Take, for example, Shanghai, China, where the municipal government has been building satellite cities in an effort to decentralise the extremely crowded city.

While this plan will increase the need for transportation to and from the various satellite cities, the government has been careful to coordinate investments in major highways with rail transit.

As part of the decentralisation plan, it also adopted strong disincentives for car ownership, including high taxes on vehicles and registration caps — all of which will likely lead to less crowded roads and less carbon emissions.

"So far, Shanghai has been a model of balanced investments in roads and transit, integrated transportation and urban land use planning, and effective restraint of vehicle ownership and use," says the report.

Whether Shanghai can continue to manage transportation demands while minimising greenhouse gas emissions as it expands economically remains to be seen, it adds.