Environmental Engineering Reference
In-Depth Information
Figure 1.10
Naples, Florida. Some societies such as the US are extremely energy and carbon intensive. Even
many of the 'New Urbanist' developments, supposedly more attractive for walking and cycling
and low in emissions, remain very car dependent, accounting for a disproportionate amount of
finite resource 'spend'.
(Thomson, 1977; Gwilliam, 2002). A car-dependent US city would require an approximate
95 per cent CO2 emissions reduction within transport; similarly a Western city with extensive
public transport networks (e.g. London) around a 60-80 per cent CO2 emissions reduction,
and an Asian city with current low vehicle mobility (e.g. Delhi) may target an increase on
current levels of around +200 per cent, all on 1990 levels. This increase in current CO2
emission levels for the emerging countries is consistent with the 'developmental imperative'
- the poorer nations have contributed only marginally to historical CO2 emissions and must
have the chance to develop even if this raises their emissions in the short term (Giddens,
2009). The key is to avoid, and achieve a reduction against, the business as usual (BAU)
projection. These types of futures are all dramatic 'trend-breaks', but represent the scale of
change implied by the strategic CO2 emission targets that are being adopted around the world.
Targets set against historic emissions would be even more stringent for the industrialised West.
The difficulty is that this scale of change is not even being discussed by governments,
industry or business, and the consequent implications for energy supplies, car production and
distribution does not seem to be a key concern. Transport does not feature as a key sector in
the IPCC debates, or at the COP meetings, and the growth in CO2 emissions from aviation
and shipping have not yet been seriously discussed in any global forum. Yet it is in these
sectors that much of the future growth in emissions will be concentrated.
Thomson's typology (1977) on city form and transport still serves as a benchmark on the
ranges of choices available at the city level (
Table 1.2
and
Figure 1.14
)
. But perhaps we now
