KEY POINTS:
Often steaming in international waters far from land, the world's fleet of ocean-going ships has largely evaded scrutiny as a source of harmful air pollution and global warming emissions.
But this lack of regulation is about to change as the fleet, which carries 90 per cent of trade by volume, expands rapidly and pressure increases to impose tighter fuel and other standards on the trillion-dollar shipping industry.
Calls are also growing louder to include both the shipping and aviation industries in any new international deal to cut greenhouse emissions. Neither is covered by the Kyoto protocol which expires in 2012.
The clean-up proposals are being closely watched by major Asian ports such as Singapore, Shanghai and Hong Kong because they will add substantially to business costs and could give other maritime centres a competitive advantage unless the new controls are adopted and enforced by all trading nations.
A report last month by four environmental groups in the United States found that only six countries emitted more carbon dioxide, the main greenhouse gas, than the world's fleet of 60,000 ocean-going and other marine vessels.
It said the fleet released between 600 and 900 million tonnes of CO2 each year, equivalent to emissions from at least 130 million cars - about the number on US roads.
But shipping industry officials say it is hard to measure CO2 pollution from the global fleet and that some estimates are exaggerated. A figure frequently cited by the industry is a report to the British Government by former World Bank chief economist Nicholas Stern.
It concluded that CO2 emissions from ships contributed just 2 per cent to the global total in 2000, compared with 15 per cent from the transport sector as a whole.
Critics insist the level is substantially higher and fails to take account of the rapid expansion of seaborne trade, which has surged by 50 per cent in the past 15 years.
Ships are also a source of non-CO2 pollution. The International Council on Clean Transportation, made up of transport and air quality officials from a wide range of states, reported last year that sea-going ships produced more sulphur dioxide than all the world's cars, trucks and buses combined.
The council's study showed that the sulphur content of marine bunker fuel is far greater than highway diesel fuel. Bunker fuel is significantly cheaper than road fuel.
Environmental groups say ships account for between 8 per cent and 10 per cent of sulphur emissions from all types of fossil fuel and also contribute nearly 30 per cent of global releases of nitrogen oxides. These emissions harm human health, cause acid rain and deplete the ozone layer.
Critics say another pollutant from ships, black carbon, or soot, can warm the atmosphere many times more than the same amount of CO2.
In November, reacting to public concern about pollution from ships, the European Commission called on the International Maritime Organisation, the United Nations agency responsible for regulating shipping and marine pollution, to do more to help combat climate change.
The IMO set up a scientific group in July to study the issue. The group included experts from major shipping and trading nations, among them China, Japan and Singapore, as well as non-governmental organisations.
Their report is due to presented at an IMO meeting in London next month.
Any proposals to tighten fuel standards, reduce funnel exhaust gases and use only shore-based electric power when in port would be included as amendments to global marine pollution laws under the organisation's Marpol Convention. They could be adopted as early as October and come into force 16 months later.
Some ship owners and government officials have cautioned the industry to take a conservative approach to pollution cuts because of the potential costs involved.
But Tony Mason, secretary general of the International Chamber of Shipping, warned last month that if governments and industry could not come up with improved standards by the end of this year "we shall see a serious disenchantment with the Maritime Organisation process and a proliferation of local regulations, led in all probability by the EU and the US."
National and regional regulation has already begun in America and Europe. For example, the US House of Representatives approved legislation in March to empower the US Coast Guard and the Environmental Protection Agency to develop and enforce emission limits on thousands of domestic and foreign-flagged ships that enter US waters each year.
If the IMO fails to come up with credible and enforceable global standards, sea-based transportation will be saddled with a patchwork quilt of regulation.
This will slow shipping and maritime trade and increase its cost.
* The writer, a former Asia editor of the International Herald Tribune, is visiting senior research fellow at the Institute of South East Asian Studies, Singapore.
