Future scenarios and strategic choices - Transport Policy and Planning in Great Britain - page 405

report the recommendations of the Stern Review on Climate Change (24.3) and the
Eddington Study on Transport and the Economy (24.5). (The reports by Kate Barker
on Housing Supply and the Planning System were produced in a similar vein and have
been noted previously.)
Around these sections we interpose other material relevant to longer term policy
options - an initial reflection on 'thinking about the future' (24.2) and examples of
scenarios offered by non-Government sources (24.4) and (24.6).
We conclude by noting the DfT's response to the Stern and Eddington reports as
contained in its White Paper published towards the end of 2007 and its intended plan
of work for a post-2014 strategy including a 'refresh' of NATA (24.7).
24.2 Thinking about the future
Before reporting work on longer term scenarios it is helpful to reflect on the ways in
which this is different from the more immediate policy-making and planning which has
been the subject of the rest of this topic. Instead of considering options for fulfilling
a particular specification (e.g. relieving traffic or environmental problems within an
area, given forecasts of relevant socio-economic variables) the task is more a matter of
identifying what the specification should be, given a high degree of uncertainty about
its context.
In one sense this uncertainty represents a positive opportunity since it offers room
for manoeuvre to 'shape' the future. (Instead of anticipating what the future will be -
so that we can plan accordingly - we are more in the position of trying to answer the
question of what we would like it to be.) In another sense however the uncertainty
inhibits strategic decision-making because of fears that it will prove 'wrong', involve
wasted expenditure and bequeath to future generations dysfunctional forms of cities
and regions which do not fulfil their economic and social needs.
Some of the uncertainty derives from projecting over a relatively long period basic
travel parameters which are known to vary over time, but within limited bounds of
probability (e.g. population, migration, economic activity, income, car ownership etc.).
This can be accommodated by identifying high and low estimates which can be used
for robustness testing whilst main strategies are evaluated against mid-range forecasts
(Chatterjee and Gordon 2006).
However there are other types of uncertainty which are more problematic, either
because they are known about but are inherently less predictable or because they
concern some eventuality which literally has not occurred before. Leaving aside the
apocalyptic possibilities of war, disease, famine etc. (but not global warming which
we consider in the next section) these uncertainties can be divided broadly into the
technical and the social.
Technical uncertainty can be subdivided into factors influencing the need or
demand for travel on the one hand and factors affecting the nature of the transport
options available on the other. Technical innovation can alter the types of activity
undertaken but also - through the development of information and communication
technology (ICT) - whether it is necessary to travel to participate in them. This applies
in fields as various as office work, entertainment, shopping, obtaining information
and advice and socialising. (For further discussion of this dimension see Chapter 9 of
Banister 2005 and Lyons and Kenyon 2006.)
Technical innovation in transport itself is less a matter of wholly new 'inventions'
than the extent to which a combination of economic, institutional and social factors