Don't compare us to aviation. Shipping is carbon-friendly

Our industry carries 80% of world trade. To switch to air freight would be a disaster, says Mark
Mark Brownrigg
The Guardian,
Tuesday February 19 2008

This article appeared in the Guardian on Tuesday February 19 2008 on p33 of the Leaders & reply section. It was last updated at 00:04 on February 19 2008. It is a reply to an article.

Readers of your front-page story would be forgiven for thinking that shipping is inefficient in terms of CO2 emissions and should be targeted in efforts to reduce greenhouse-gas emissions (True scale of CO2 emissions from shipping revealed, February 13). Even aviation is only "responsible for about 650m tonnes of CO2 emissions a year, just over half that from shipping", you report.

Perhaps we should park all the ships and send the trade by air? That would be a catastrophe for the environment - as well as a physical impossibility! Air freight produces 100 times as much CO2 per tonne kilometre. Such a move would quadruple total man-made CO2 emissions. This is a measure of the carbon-friendly nature of the shipping industry - although the industry is far from complacent and continues to work to reduce CO2 output.
Shipping carries 80% of world trade and 92% of British trade. It is a vastly bigger industry than aviation and performs a completely different role. The well-established multiplier effect of emissions at high altitude also makes comparisons difficult.

Last year the Guardian reported that shipping contributed 5% of total CO2 emissions (CO2 output from shipping twice as much as airlines, March 3, 2007); now, describing it as "three times higher than previously thought", it claims the figure is 4.5%. In truth, the shipping industry is so complex and international that there will probably always be a range of estimates for fuel usage and CO2 emissions. But the figures in the report submitted to the International Maritime Organisation (the UN body for shipping) make a valuable contribution to the development of a baseline figure on which to assess industry efforts to reduce emissions.
Shipping has already vastly improved its carbon performance - through efficiencies of scale and engine consumption. Today's container ships emit about a quarter of the CO2 that they did in the 70s - while carrying up to 10 times more cargo.

The real focus of the IMO report, however, was the reduction of air pollution from ships (CO2 is not classed as a pollutant but as a greenhouse gas). The report itself was not concerned with carbon emissions per se, except in terms of assessment of whether efforts to reduce air pollution from ships may actually raise their carbon footprint.

It is a pity that your article missed the main thrust of the report - the evaluation of the impact of practical options to reduce emissions of air pollutants (sulphur oxides and particulate matter) from ships. The report made a major contribution to the revision of air emission legislation by the IMO. This should see a considerable lowering of global emissions of air pollutants worldwide by 2009. This is good news for the environment and for the health of those people affected by these emissions, and the shipping industry contributed positively and substantively to the debate.

· Mark Brownrigg is director-general of the Chamber of Shipping press@british-shipping.org