Weather –

September 2009, Vol. 64, N

o. 9

251

Invoking the precautionary principle

I was intrigued by the letter from Paul

Simons published in the April edition of

Weather (Simons, 2009).

For much of the early part of my career

I was involved with research into trans-

boundary air pollution and worked with

colleagues from several different countries.

We were searching for a full, clear, scientific

understanding of the phenomenon and

there was a great spirit of co-operation;

many are still friends today. Then the poli-

ticians, policy-makers, big business and the

media became involved. Individuals from

these groupings seemed unable or unwill-

ing to retain more than a few scientific facts

and took a very partial view of scientific real-

ity. Objectivity was sacrificed. They muddied

the waters to such an extent that the general

public was unable to take an informed view

on the issue. I see many parallels between

the evolution of public perception on the

problem of atmospheric acidity and that of

climate change.

My take on the latter is that any opinion

on climate change needs to be assessed in

the context of paleoclimatology. For most of

its geological history, this planet has not had

permanent ice caps: we currently exist in a

relatively rare Ice Age. During this Ice Age,

Earth has experienced four glacial advances

(media to note!) each more extensive than

its predecessor. Currently there is an inter-

glacial, with slightly warmer weather. It is

not known how long this period will last.

Superimposed on our present variable and

climatologically atypical baseline are man’s

inadvertent modifications of the climate.

The bulk emission of radiatively active

gases will undoubtedly be altering what

would otherwise be the present ‘natural’ cli-

mate but exactly how and by how much is

uncertain; the effect of these gases on the

natural climate will have been suppressed

since the dawn of the Industrial Revolution

by the emission of other pollutants, particu-

larly sulphur dioxide (sulphates) and dark

particulate matter, both of which exert a

strong effect on albedo. With the coming of

the Large Combustion Plant Directive and

National Emission Ceilings directives, these

emissions, at least in Europe, have been sig-

nificantly reduced allowing the accumulated

radiative forcing effect of carbon dioxide and

its cohorts to make themselves fully felt.

Many commentators express deep con-

cern about man’s inadvertent modification

of climate and the dire predictions of worse

to come. These predictions may – or may

not – come about but invoking the Precau-

tionary Principle it is appropriate for poli-

cy-makers to consider aversion strategies.

To my mind, there is only one that will be

effective: don’t have children. It is people

who consume and emit. Anyone who thinks

that the present or, worse still, the predicted

global human population can survive indefi-

nitely at the present standard of living is liv-

ing in cloud cuckoo land. The real villain of

the piece is the economic model on which

all global economies have been predicated

since the Industrial Revolution: increased

consumption fuelled by an increasing pop-

ulation to provide an ever-increasing mar-

ket and low labour costs. Conveniently this

ignores the reality that we live on a finite

planet with finite resources, some of which

will be exhausted long before the worst

predictions of climate change come about.

Perhaps Mr Simons’s readers are taking a

broader perspective of the climate change

issue than he would give them credit for.

ReferenceSimons P. 2009. The public perception of climate change. Weather 64:167.

Ron Barnes

Wantage

DOI: 10.1002/wea.478

The public perception of climate change

Paul Simons’s letter on this subject is very

timely (Simons, 2009). In dealing with the

problem he highlights, it will not be enough

to simply rely on the fact that there is an

overwhelming scientific consensus.

The convincing response that is needed

should deal inter alia with the questions

relating to the variations that are on the

historical record. At a time when emissions

from industry and transport were non-

existent, what specific natural mechanisms

caused the medieval warming, followed

by the sixteenth–eighteenth-century cool-

ing? In the twentieth century, when emis-

sions from industry were growing rapidly,

what was the mechanism that led to the

1960–1980 cooling? The late-twentieth-

century warming seems to have stalled in

this century. Why has this happened when

emissions are continuing to rise? Are we on

the verge of another ‘natural’ cooling which

could be mitigated by man-made changes

to the atmosphere?

Without clear and detailed explanations

of the natural fluctuations of the past and

present, it will be difficult for the genuine-

ly concerned person to relate these to the

mechanism of climate change due to man-

made causes.

Reference Simons P. 2009. The public perception of

climate change. Weather 64:167.

R.N. Simeone

Surrey

DOI: 10.1002/wea.479

An anthill takes over the rain gauge at Moulton Park climatological sta-

tion (WMO 99115), Northampton, which had recently been converted

to automatic operation after nearly 33 years of manual observing at

the site. The photograph was sent to us by the station’s observer, Greg

Spellman, who comments: long live manual stations and their daily

inspections which allow disruption to be noticed quickly!

Letters