Letters: People and petrol
Lee Schipper questions the veracity of our data on population density
versus petrol consumption in cities (Letters, 21 August).
Toronto is an outlier on the graph as shown and in our book we do explain
that the line around that city marks the metropolitan area not the Toronto
region. We have recently obtained much better data which shows we overestimated
Toronto’s car use. The new data, whether on the metro area or region, show
Toronto pulls back right onto the line. None of our other data has been
questioned by any of the city authorities we used to help compile our study.
Since publishing our graph we have had around 15 other cities analysed
by us or others for their car use (petrol consumption) and density – from
Bangkok to Auckland. All of them fit onto the line.
The ‘sketchy’ data about cars is in fact developed in a standard traffic
engineering model by all cities based on screenline traffic data and is
universally accepted around the world. It is not good at predicting future
traffic but it is very good at describing the present. In Australia we survey
car use through travel diaries as well as using the traffic model – they
are remarkably similar.
We do not find out petrol data from petrol sales because of the problems
Schipper raises about where filling stations are located and the use by
rural residents. We calculate it from vehicle data. Our graph does show
the mobility of people living in the city, contrary to his assertion.
We have also collected data within many cities and find the same strong
relationship between the level of car use and density – particularly a spectacular
increase below 20 to 30 people per hectare. This is the same despite some
cities, for example in the US, which have wealthy people living on the low
density fringe, or in Australian cities where poor people are on the fringe.
We have never said that density alone exerts some magic on transport
patterns – obviously petrol price, income and car ownership are important
(the latter is closely linked to density also) as is the level of transit
service provided compared to roads and the importance of subcentres. However
density cannot be dismissed either – it is a fundamental factor in why Stockholm,
for example, has 5 times less per capita petrol use than San Francisco –
two cities Lee Schipper knows well. I do not believe Stockholm is any the
less a place to live in for its higher density. It illustrates, as Lee Schipper
did so effectively in his energy use studies in the seventies, that Europe
has a few things to teach the New World about living more sustainably.
Peter Newman Murdoch University Perth, Australia
Letters: Coining it
Following Feedback’s comment that the 1p coin is redundant (2 October),
I feel obliged to point out that this is plainly untrue. Anyone who shops
on even an occasional basis will realise that, until the long overdue introduction
of the 拢0.99 coin (and 拢4.99 note), the future of the 1p
coin is assured.
M. Locker Randlay, Telford
Letters: Selling space
Some doughnuts have no hole in the middle and thus might seem to contradict
the uncooked centre explanation (Letters, 25 September). That is, until
you remember they invariably contain jam or custard which, as the unwary
gourmet discovers on biting into a newly cooked one, can hold a considerable
amount of heat – sufficient perhaps to ensure an evenly cooked centre?
However, I suspect that the real reason for the hole in the former type
is merely yet another example of a clever packaging ploy used for the purpose
of marketing empty spaces to an unsuspecting public. Other examples include
Polo mints, flat shampoo bottles, innumerable food and beauty products in
round jars with large caps, false bottoms packed into square cartons, and
junior science kits in presentation boxes . . .
M. H. de T. Andrews London
Letters: Give us the Earth
My own association would agree that the content of the National Curriculum
is overloaded, and that it would have been much better if the subject committees
had communicated with each other before the whole system was launched. We
can also sympathise with the chemists in particular: up until the last review
of the curriculum, earth sciences stood alone as an Attainment Target. Then
at the last minute it was slotted into the ‘chemistry’ group and is thus
perceived by chemists as an interloper.
However, John Holman’s view that earth sciences should simply be deleted
(Forum, 25 September) seems to us to stem from teachers’ unfamiliarity with
the subject, leading to insecurity in teaching it.
We are convinced that all children should be able to understand their
planet more fully, and to appreciate it as the provider of everything that
is needed for life. As it is, the Programme of Study for Science provides
for breadth, relevance and enjoyment across the sciences and any attempt
to delete earth sciences would be disastrous.
Many perceive overlap between science and geography in the National
Curriculum, and we do hear of schools where the geography department is
left to teach all the earth sciences.
In our view, there is little overlap – science can concentrate on the
investigational aspects of earth processes etc, and geography on the resultant
landforms and some of the human response. However, some clarification is
needed – for example, in defining why the unifying theory of plate tectonics
is seen as a Level 10 concept in science, but is taught at Level 5 in geography!
Clearly, there is still much work to do in the redefinition of the National
Curriculum, but not at the expense of earth sciences.
Peter Kennett Earth Science Teachers’ Association Sheffield
Letters: Give us the Earth
Thank you for volunteering earth sciences for your personal effort of
blood-letting; the only trouble is, I don’t think it will be willingly put
its head on the block.
The proven success of earth sciences in the curriculum lies in the fact
that most projects involve observations and comparisons which can be made
in the surroundings of almost any school. Kerbstones, pavings, gravestones
and building stones (the school itself) offer the crustal materials which
can be the basis for studies in weathering. The teacher has an opportunity
to translate science into the everyday with a minimum of theory.
Early stages can linger over a child’s fascination with collecting,
classifying shapes, colour or textures to the point where the difficult
names of rocks, minerals or fossils become a natural sequel.
What’s more, earth sciences has become much more flexible in recent
years and is no longer restricted to recognition. It can play an active
role in the favourite environmental issues which figure regularly in the
popular press – crustal stability, pollution and sea level change, to name
but three.
As for the tug of war between chemistry and geography, in some ways
this rests with the training of teachers which in the past lacked more than
a token element of geology. Surely from now on, earth sciences will figure
more prominently in teacher training in its own right. Eric Robinson
The Geologists’ Association London
Letters: Resolving conflicts
David Pearce and Dominic Moran are in error when they claim (Letters,
9 October) that there is a ‘total lack of any constructive alternative’
to cost-benefit analysis in ‘making social decisions’. Most reasoned social
decisions are made not by calibrating alternatives along a ‘neutral’ scale
(in most contexts of argumentation, such as those having to do with rights
or intercultural differences, such a scale does not exist and to impose
one would be dictatorial). Instead, they are made by a processes of consensus-seeking
and mutual learning in which conflict resolution methods are contested and
preferences are open to rational revision.
Such processes can be most constructive, as anyone knows who has sat
through a long meeting in which participants of diverse backgrounds try
to decide an important issue and find their preferences changing in light
of their discussion with others. Yet cost-benefit analysis is useless in
advancing such processes, since it presupposes fixed individual preferences
ready-made for quantification and imposes in advance a single shared system
of conflict resolution.
Pearce and Moran suggest that those who oppose an expanded reliance
on cost-benefit analysis in political life are antidemocrats who do not
want the majority’s preferences to count. In fact, however, most of those
opposed are democratic and realise that commensurating wants belonging to
different cultures and contexts of appraisal is often an undemocratic procedure.
Larry Lohmann and Sarah Sexton The Ecologist Sturminster Newton, Dorset
Letters: Resolving conflicts
Anybody familiar with the ongoing dialogue between David Pearce and
John Adams could not fail to notice that, as has happened several times
since their argument first started twenty years ago in The Ecologist, it
is once again following the same predictable path. Adams attacks cost-benefit
analysis, Pearce counterattacks by accusing Adams of ignorance, Adams defends
by attacking Pearce, and so it goes on.
As a reader, I look forward to the day when the pair of them discover
the now well-developed and rational techniques of conflict resolution. They
might then discover ways in which some kind of synthesis of their views
adds up to more than the sum of the parts and produces a new insight.
Juliet Solomon London
Letters: Eurofest
The objective of the European Week for Scientific Culture was never
to organise communication between 320 million individuals, as your editorial
of 25 September makes out. This initiative was designed as an experimental
activity, a kind of prepublication edition. The aim is to show that it is
both possible and valuable to do this kind of thing at a European level
too.
The projects which make up the European Week are indeed European both
in content and in the way they operate. They have been put together by organisations
from many different countries working in collaboration. So, as well as science
itself, it is science in its European dimension which will be presented.
That means European scientific cooperation, and science in other European
countries: different personalities, ways of working and making it known.
Surely it is premature, to say the least, to claim that these projects will
have no impact before they even take place.
Along with European Week, national science weeks are tending to multiply,
and this must be a matter for congratulation. Could they not be combined,
with each other and with the European Week? We will only be able to answer
that question when the 1993 edition of the European Week has taken place.
At the same time we will be able to decide how, in 1994 and beyond, all
the efforts which are made in Europe to improve the understanding of science
can most effectively be organised.
A. Ruberti Vice-President of the Commission of the European Communities
Responsible for Research and Education Brussels
Letters: Affluence to blame
Gail Vines reports an interesting hypothesis (This Week, 25 September)
relating increased breast cancer mortality to a supposed increase in exposure
to ‘oestrogen-like’ pesticides in the environment. While laboratory studies
may have established a possible biochemical link between oestrogen and uncontrolled
cell division, there is little direct epidemiological evidence of a link
between pesticide exposure and breast cancer. Indeed crude mortality is
rising in most developed nations at a broadly similar rate, despite tremendous
differences in agricultural practices and urbanisation.
It is interesting to note that US breast cancer mortality has actually
been falling at 1 per cent per year among women under 55, and that the overall
increase is entirely attributable to increasing mortality among older women.
Therefore, the pattern of mortality could also be explained by successful
therapy and increasing survival rates as by any putative pesticide exposure.
It is a common misconception to blame increasing cancer mortality upon
a worsening environment. The successful eradication of many infectious diseases
and continuing reductions in mortality from circulatory disorders have shifted
the balance from preventable to unpreventable death. Every time a ‘major
killer’ is conquered, a previously less significant condition will take
its place at the top of the list.
Competitive modelling of the reduction in preventable mortality demonstrates
a clear link with factors of affluence, social class and general health,
which are all known and replicable epidemiological correlates of elevated
breast cancer mortality. It also demonstrates that just under 5 per cent
of American women would die from breast cancer in the absence of other causes
of death, and that this proportion is stable.
Even in the UK where crude rates of breast cancer mortality are much
greater (53 deaths per 100 000 women as opposed to 30 in the US) this proportion
is still just under 7 per cent. It is a natural consequence of rising life
expectancy that more of these women will die later from breast cancer rather
than earlier from unrelated conditions.
Stuart Neilson Brunel University Uxbridge, Middlesex
Letters: Fatal puff
Re ‘Legal Drugs’ (‘Life, the Universe and (almost) everything’, 18 September):
I think there has been some confusion with milli and micrograms. One puff
of a cigarette does not contain 350 milligrams of nicotine – if it did,
smoking would certainly be injurious to health – instantly fatal.
David Hughes Barton Hartshorn, Buckinghamshire