Examination of Witnesses (Questions 220
- 239)
WEDNESDAY 11 FEBRUARY 2004
DR ANDREW
SENTANCE
Q220 Gregory Barker: But do you accept
that there must ultimately be a point where demand management
should become a matter of public policy, as we are seeing with
roads, for example?
Dr Sentance: I do not believe
that it is efficient or appropriate to target the growth of any
particular activity that generates wide economic and social benefits
when what you are really concerned about is the environmental
impact that it has. You should be trying to limit the environmental
impacts and develop economic instruments or other instruments
that will effectively achieve that. There has been a long running
debate about whether we should slow down economic growth in some
way because economic growth is damaging intrinsically to the environment.
I think the outcome of that debate is really to say that is not
the way we should go. What we should have is more environmentally
efficient growth, growth that can then actually be consistent
with reducing environmental impacts and improving the environment.
I think demand management, as I understand it being advocated
by Jeff Gazzard and others, is really going back to the old-fashioned
notion of saying you slow down the growth of things, economic
growth and economic and social benefits, in order to get environmental
improvements. I think the way we are proposing is that you actually
try and get more environmentally efficient growth and then let
the market decide what the growth rate is.
Q221 Gregory Barker: But you are
not going to get environmental neutral growth, are you? You are
just going to mitigate the environmental damage.
Dr Sentance: Well, you need to
look at each environmental impact on its merits in making that
assessment. There are three major issues we need to concern ourselves
with—noise, local air quality impacts (particularly from
nitrogen oxides around airports) and global warming. In the noise
case it is very much directly linked with the activity of the
industry. Now, what has actually been achieved there, even at
growing and busy airports like Heathrow, is actually reductions
in the noise footprint through technological improvement through
higher standards even though the industry has been able to grow.
On the local air quality side at airports it is a mixture of what
is generated by the airport and what is generated by other sources,
particularly road traffic. You need an approach that takes all
those into account. We are working to develop frameworks for that
and we will need to put that in place if we are going to develop
in Heathrow. In the case of global warming, aviation is a small
part of the overall global picture and we are concerned about
the global picture. That means that aviation needs to play its
part but it must do so within a framework that is dealing with
the overall global impact and to just target one industry and
its global warming contribution would be unreasonable. All industries
should be expected to be part of a global framework in which they
deal with that issue.
Q222 Gregory Barker: Would that common
framework be sustainable consumption, and if so how would you
define that?
Dr Sentance: The notion of sustainable
consumption depends very much on how you define it.
Q223 Gregory Barker: I am asking
you how you define it.
Dr Sentance: Well, I think what
we would say for aviation is that it needs to be part of a sustainable
economy, in other words we need an aviation industry that contributes
to an economy that delivers a sustainable balance of economic,
social and environmental benefits. That does not mean, in our
view, cutting off the very big economic and social benefits that
aviation delivers. In fact delivering those economic benefits
and actually generating adequate financial returns from them is
part of the process through which aviation is then able to gain
the funds for investment into dealing with its environmental problems.
What we have got to do is to make sure that aviation is playing
its part and, as I have said, in each of those three areas—noise,
local airport air quality and global warming—the way in
which aviation plays its part needs to be identified differently.
Having a blunderbuss approach of saying, "Let's just slow
down the growth of the industry and stop the industry in its tracks,"
I do not think is the best way of achieving an aviation contribution
to a sustainable economy.
Q224 Chairman: Just for the record,
I do not think anyone is saying, "Stop the industry in its
tracks." What Mr Gazzard seemed to be saying was, "Halve
the rate of growth," which is a very different matter.
Dr Sentance: What I am referring
to are instruments which are designed purely to slow down the
growth of the industry rather than instruments which are designed
to deal with the environmental impact of the industry.
Q225 Gregory Barker: The Department
for Transport South East consultation document showed that traffic
would rise only from 153 million passengers per annum (mppa) to
185 mppa if no runways were built, whereas it would rise from
153 to 249 million passengers per annum if one extra runway was
built at both Heathrow and Stansted. That represents an increase
of 63%, if my maths is right, against the baseline as opposed
to only 21% for a maximum use scenario, yet in paragraph 3 of
your annexe[11]
you say that preventing runway expansion would reduce UK carbon
emissions by at most 1.6% in 2030. How do you justify that or
reconcile it?
Dr Sentance: The figure quoted
in paragraph 3 of the annexe to my note is derived from Government
figures but the 1.6% is of the total UK carbon dioxide total.
So it is not 1.6% of aviation's contribution, it is 1.6% of the
UK total, which is about 600 million.
Q226 Gregory Barker: Is it not a
bit misleading?
Dr Sentance: I think it is correct
in what it says.
Q227 Gregory Barker: But do you think
it is misleading in that context?
Dr Sentance: No, I do not think
so.
Q228 Gregory Barker: Why did you
not use the aviation figure?
Dr Sentance: Because what I was
trying to point out in this note is that it would make a very
limited contribution to the overall UK's challenge of reducing
total UK carbon dioxide emissions.
Q229 Mr Thomas: Could I just come
in on that, Chairman. Very specifically the report of this Committee
which we did in July 2003[12],
because we are talking about 1.6% and we are talking about 2030,
this Committee found that the impact of aviation emissions together
with radiative forcing was going to be in the order of 175-200
million tonnes CO2 by the year 2030, whereas the 2050
target, as we know, is 229 million tonnes of CO2. So
it seems to me that this Committee concluded that by 2030 the
growth in aviation, that we have seen under this scenario that
Mr Barker was asking you about, would account for 90% of the UK's
2050 target. So your earlier comment that this was a small part
in the overall position—I acknowledge you put it in the
global picture, not the UK picture—and your comment now
about this 1.6% is surely untenable?
Dr Sentance: There is a number
of differences between the figures that you are quoting to me
and the figures that I have looked at. First of all, I am looking
at what the impact of not providing the runway expansion is, whereas
you are obviously looking at the overall total figure. Secondly,
I am concentrating on carbon dioxide and I am very clear in the
paper—
Q230 Mr Thomas: So you are not taking
account of radiative forcing?
Dr Sentance: We are not taking
account of radiative forcing, though in other analyses that we
produce later in this paper we do take into account radiative
forcing. Those make two important differences. The third important
difference is I am using a 2000 base, in other words I am not
making judgments about what targets might be set in the future
and clearly as you reduce the overall total that you are targeting
any given amount becomes a larger proportion of that.
Q231 Mr Thomas: Are you not including
radiative forcing because you dispute the science of it or because
it is convenient not to include it?
Dr Sentance: We are not including
radiative forcing for a number of reasons. One is we do not believe
that the science is sufficiently developed for policy action.
Q232 Mr Thomas: So you reject the
International Panel of Climate Change's 1999 report?
Dr Sentance: We do not reject
the report. The report showed a great range of uncertainty around
the estimate.
Q233 Mr Thomas: But they concluded
2.7, did they not?
Dr Sentance: 2.7 is the average.
They showed it was somewhere between 1 and 10, I think, somewhere
in that range. It is a very wide range.
Q234 Mr Thomas: Can we settle for
the Government's 2.5 then?
Dr Sentance: I do not know whether
you have had any discussions with the scientists who have looked
at this—
Q235 Mr Thomas: No, only the Government,
not the scientists.
Dr Sentance: Right. As you talk
with them you appreciate what a great deal of uncertainty there
is in this area and, secondly, about how uncertain we are about
the best way to deal with this. With carbon dioxide we are pretty
clear that carbon dioxide generates global warming through the
mass of it that is around and that if we limit the mass of it
that is around we will get a global warming benefit. With these
other upper atmosphere effects there are all sorts of theories
around about how they might be reduced and limited and until we
really have a much better understanding of that—and we do
very much support research to get a much better understanding
on quite an urgent timescale—we do not think it is appropriate
to put policy instruments in place.
Q236 Mr Thomas: So you do doubt the
science, at least in terms of doubting that the science gives
the policy makers—
Dr Sentance: We think the science
is okay as far as it goes but it has not taken us far enough into
it to start developing policy instruments.
Q237 Chairman: You say you support
research. Are you aware of the Trade-Off research which was commissioned
by the EC, which was published recently, which came up in the
end with a best estimate figure of the radiative forcing multiplier
of 4.4, considerably higher than the 2.5 being used by the Treasury?
Dr Sentance: This goes to highlight
that, you know, there is still a lot of uncertainty about it.
Q238 Chairman: There is uncertainty
but the drift is upwards and to deny in your evidence that it
exists at all I think is disingenuous.
Dr Sentance: We are not denying
that it exists at all, but I think it is quite legitimate and
sensible to ensure that the scientific basis is correct before
we move to policy action because we are not clear what the most
efficient way of dealing with these effects is.
Q239 Chairman: Are you aware of the
precautionary principle?
Dr Sentance: I am aware of the
precautionary principle. The precautionary principle, however,
has various elements built into it which says that you need to
take action on a cost effective basis. Adding multipliers of 2,
3, 4, or 5 to carbon dioxide effects is not necessarily a very
cost effective way forward.
11 Please see memorandum, Ev 65. Back
12
Budget 2003 and Aviation, Ninth Report of Session 2002-03, HC
672. Back
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