Notes

1. A possibility that arises from the very differentiated nature of truck transport, which involves vehicles of different sizes, weight power ratios, and resource productivity.

2. Judged on an economic growth criterion, impressive progress has been made under the regime. Between 1950 and 1990, real ($ adjusted) gross world product increased five-fold from US$3.8 trillion to US$18.8 trillion. On a sustainability criterion, we can be less sanguine because more rapid growth equates with more rapid conversion of environmental capital and higher rates of environmental change.

3. Both are alleged to cost 1 2 per cent of GDP in countries lightly affected by distortions and 3 5 per cent of GDP in countries with severe distortions (Repetto 1993).

4. A prediction that prompted the Task Force to single out transportation as the sector through which liberalization of the internal EU market would have its greatest environmental impact.

5. EU truck limits now allow truck lengths of 16.5 m. widths of 2.5 m, and gross weights of 40 50 tonnes.

6. The situation is actually even more complex than this suggests. Although some operators have increased their average truck size, the overall tendency recently has been for a shift in many OECD countries away from medium-sized trucks toward very large trucks for bulk freight and small trucks for retail distribution and high-value goods. Much of the recent growth has also been concentrated in small trucks. The environmental downside here is that these have relatively low energy efficiency per freight tonne (compared with large trucks (IPCC 1996, p. 691). Overall, it seems that the shift from medium-sized to large and small trucks has reduced overall transportation energy efficiency.

7. I have already focused heavily on the significance of distance - and the need to overcome distance - in contributing to environmental impacts. But distance has more significance than is immediately apparent in the shift toward sustainability. In respect to future sustainable societies and economies, distance is also important as: (i) a factor in the ecological viability of recycling; and (ii) a factor in the viability of service-driven business plans. As to the latter, proximity to the market will be more important as businesses shift from strategies based upon selling goods (the service delivery machinery) to those based upon selling services. Radical increases in resource productivity will depend upon such shifts (Ayres and Schmidt Bleek 1993).