Global Environmental Change 13 (2003) 185–194

ARTICLE IN PRESS

*Correspondin

E-mail addres

0959-3780/$ - see

doi:10.1016/S095

Do natural science experiments influence public attitudestowards environmental problems?

Astrid Wallner*, Marcel Hunziker, Felix Kienast

Swiss Federal Research Institute WSL, Zuercherstrasse 111, 8903 Birmensdorf, Switzerland

Abstract

We investigated the significance of risk assessment studies in the public discussion on CO2 emissions. Politicians and

representatives from the public where interviewed by using the social-science technique of qualitative in-depth interviews.

Three different types of attitudes towards natural science were found among politicians. Depending on which attitude a politician

holds, risk assessment studies can have an impact on his/her readiness to support environmental policy measures.

Regarding lay people, key factors affecting the acceptance of environmental policy measures are knowledge of environmental

problems, their impacts on ecosystems or human health as well as direct personal perception of those impacts. Since direct perception is

not always possible in everyday life, natural science experiments might be a means for successfully mediating this lacking perception.

r 2003 Elsevier Ltd. All rights reserved.

Keywords: Risk assessment; Risk communication; Acceptance; Public opinion; Social science; Model-ecosystems

1 In the so-called ICAT project (ICAT = Impact of elevated CO2

levels, climate change and air pollutants on tree physiology), natural

scientists studied the effect of elevated CO2 in beech-spruce model-

ecosystems. Those model forests were planted in 16 open-top chambers

and were exposed to either ambient or elevated CO2 concentrations

1. Introduction

1.1. Problem and objectives

Our industrial society releases compounds to theenvironment, which influence all living organisms(Brunold et al., 2000). Governments are challenged totake an active role in the management of risks associatedwith global warming, ozone depletion, air pollution,acid rain, water contamination and waste disposal. Buthow do politicians decide which environmental policymeasures are advisable? There are several dimensionsthat complicate decision making in environmental riskmanagement (Segerson, 1992). For example, choices inenvironmental policy have to be made today, but thefuture effects of these choices are uncertain. At the sametime most environmental risks are of composite natureand therefore an overall policy is needed, whichcoordinates and balances the different possibilities ofintervention. Furthermore, it is important to be awarethat possible negative impacts of environmental risks areirreversible, meaning that they cannot be undone bysubsequent action: ‘‘The possibility of irreversible effectsmakes current policy decisions particularly important,since recovery from bad decisions is not possible. In

g author. Tel.: +41 1 739 24 65; fax: +41 1 739 25 88.

s: astrid.wallner@wsl.ch (A. Wallner).

front matter r 2003 Elsevier Ltd. All rights reserved.

9-3780(03)00042-6

other words, we must live with the consequences ofcurrent policy choices without the possibility of futurerectification’’ (Segerson, 1992, p. 113).

How can these problems in environmental policyformation be solved? Could risk assessment studies—amethod used to analyse the adverse effects caused by asubstance, activity, or natural phenomena (Cohen,1997)—help politicians in opinion formation and policymaking regarding environmental problems?

The focus of this paper lies in the significance of riskassessment studies in the public discussion on environ-mental problems. On the basis of qualitative in-depthinterviews with a small sample of politicians and citizensof Switzerland, we attempted to find typical patterns ofthe relation of risk assessments to opinion formationand policy making. This study was part of an interna-tional research project, which studied the influence ofatmospheric CO2 enrichment on our forests with thehelp of model-ecosystem experiments.1 As social scien-tists in this research project, we wanted to know whether

and two different N depositions. A multidisciplinary project team

investigated the carbon, water and nutrient cycles (for more informa-

tion on these experiments see Landolt et al., 1997).

ARTICLE IN PRESSA. Wallner et al. / Global Environmental Change 13 (2003) 185–194186

the results of model-ecosystem experiments furtherpoliticians’ readiness to formulate new environmentalpolicies, and whether the results of scientific experimentshelp to increase the public’s acceptance of such newpolicies. However, before presenting the results of ourstudy, the state of research on the relation betweenscience and politics as well as on environmental knowl-edge, behaviour and acceptance of environmentalpolicies has to be examined.

2. State of research

2.1. Science and politics

Scientific research is of great importance for policymaking: scientific knowledge—arguments taken fromscience or at least references to expert opinions—playsan ever increasing role in the media, public discussionand in political disputes in parliament (Freiburghausand Zimmermann, 1985). Cotton and Pielke (1992) statehow important scientific facts are in order to decide onpolicy changes: ‘‘Without solid scientific evidence thatCO2 emissions are causing significant changes inclimate, one cannot make an objective evaluation ofthe relative cost of each alternative’’ (Cotton and Pielke,1992, p. 222). But the view that ‘‘science producesobjective truth and provides a rational non-politicalbasis for policy making’’ has come under increasingcriticism (Blaikie, 1995a, p. 210). Blaikie states:‘‘Although information from natural scientists mayoften be claimed as authoritative, it is producedselectively. Therefore, it can never be understood solelyfrom the perspective of the natural sciences. Scientistsare but one set of players in the experience andinterpretation of the environment. They also negotiate,dispute and propagate their own ideas, with others’’(Blaikie, 1995b, p. 26). And Knoepfel (1992) argues thatscience is given too much political responsibility: ‘‘Whilepoliticians today often decide on pretty unimportantmatters (for example, the introduction of the daylight-saving time and so on) crucial aspects of environmentalquality are actually increasingly decided by the scientificcommunity without any precise political mandate’’(Knoepfel, 1992, p. 175).

Freiburghaus and Zimmermann (1985) distinguishfour functions of science for politics: (1) the instru-mental function—the scientist as ‘‘engineer’’ to pro-vide information on problems and possible solutions;(2) obtaining authorisation—the scientist as ‘‘supporter’’to legitimise a decision or to inform the public;(3) strategic function—the scientist as ‘‘ally’’ or as‘‘adversary’’ in the fight for power and influence;(4) enlightenment—the scientist as ‘‘educator’’ to clarifyquestions and problems and also to reflect on the stateand its activities. According to Freiburghaus and

Zimmermann, the transitions between these functionsare fluent, e.g. a technical-scientific expertise of anecological problem can at the same time be used toinform the public about complex interrelations and tojustify the idleness of the state in the face of thiscomplexity. According to Cohen (1997), there seems tobe a trend towards a greater reliance on environmentalrisk assessment in policy making. Cohen reports of asurvey of state legislators and their staff in the US,exploring their intuitive understanding of environmentalrisk and risk assessment. The survey revealed strongsupport for the use of risk assessment of most statelawmakers, but at the same time the survey also showeda belief that legislators have very little understanding ofthe risk assessment process. However, it must also berecognised that the attitudes of politicians towardsscience are not homogeneous: ‘‘Participants in policymaking have different roles, constituencies, values,interests, perspectives, and abilities. Their attitudestowards research also differ; some value it and somedo not. Moreover, among those who value it, some aregenuinely open-minded in seeking and using researchfindings, others attempt to mobilise findings forpartisan or legitimising purposes, and still othersview research in a tactical, rather than a substantivecontext’’ (Laurence, 1978 cited in Freiburghaus andZimmermann, 1985).

Another important study regarding the relationbetween science and politics is the study carried out byThe Social Learning Group (2001). By taking a long-term, multinational perspective, the Social LearningGroup looked at where conceptions of global environ-mental risks and management goals come from and howthey change. During this study, the Social LearningGroup observed a general pattern of linkages ofknowledge-intensive functions of risk assessment andthe more action-intensive functions of goal and strategyformulation. They observed that before issues such asacid rain or climate change were taken up on the policyagenda, the risks were largely treated as scientific issues.‘‘As the issues burst into the policy agenda, however, theknowledge-intensive management functions began toinfluence performance of the more action-intensivefunctions. In particular, risk assessments stimulatedgoal statements. Finally as political attention peakedand fell, there was an intensification of two-way linkagesbetween knowledge and action functions’’ (J.ager et al.,2001, p. 170).

There is a growing literature on the connection ofscience and politics regarding environmental issues(e.g. Clark and Majone, 1985; Cohen, 1997; Haaset al., 1993; Knoepfel, 1992; Litfin, 1994; Rowlands,1995). But surprisingly, in most studies, people inter-viewed regarding their attitude towards risk assessmentstudies can solely agree or disagree with fixed state-ments. Therefore it will be interesting to see, what

ARTICLE IN PRESS

2The question was ‘‘Where do high ozone concentrations pose a

threat for humans and the environment: on the ground or in the

atmosphere?’’

A. Wallner et al. / Global Environmental Change 13 (2003) 185–194 187

politicians say when asked to formulate their own ideasregarding the question of the role of science in policymaking.

2.2. Environmental knowledge, behaviour and acceptance

Does new insight into ecological processes andinformation on the impacts of one’s own action on theenvironment lead to a change in one’s behaviour?Various empirical studies have shown that there is adiscrepancy between environmental knowledge andenvironmental behaviour (e.g. Diekmann and Preisen-d .orfer, 1992; Foppa and Tanner, 1995; Franzen, 1997;Grob, 1991; Jaeger et al., 1993; Jaeggi et al., 1996; Kleyand Fietkau, 1979; Kunz, 1998; Urban, 1986). So if notknowledge and awareness, what does determine envir-onmental behaviour? According to Smith (1992), thefindings from contingent behaviour studies clearlysupport a link between risk perceptions and behaviour.Jaeger et al. (1996) evaluated three models to explainpeople’s readiness to take climate-relevant environmen-tal action. Each model uses a different set of explanatoryvariables, i.e. model A claims that information transferfrom science to the public is the key variable governingaction; model B focuses on sociodemographic charac-teristics, and model C claims that sociocultural variablessuch as interpersonal rules and social networks governpeople’s actions. According to their results, model C ismuch the strongest of the three, meaning, ‘‘the prob-ability of climate related environmental action issignificantly increased if individuals are exposed tointerpersonal rules favouring such action’’ (Jaeger et al.,1993, p. 209). According to Diekmann and Preisen-d .orfer (1992), environmental knowledge and awarenessare transformed into actual behaviour only in so-called‘‘low-cost’’ situations: people change their actions intoenvironmental behaviour in situations that do notrequire drastic changes in behaviour, do not cost a lotof time, and cause no great effort. For example, thepersonal costs of environmental behaviour are smaller inthe realms of shopping and sorting garbage than insaving energy and traffic reduction. Furthermore,environmental problems are major examples of socialdilemmas (Dawes, 1980). The dilemma situation devel-ops when the individual only sees a very small possibilitythat his own action can change the situation. In order tosolve the problem, the joint effort of a large number ofindividuals is required. Therefore, environmental qualitydisplays the same characteristics as an economiccollective good (Diekmann and Preisend .orfer, 1992;Jaeger et al., 1993).

Even though environmental knowledge and environ-mental awareness in general are not sufficient conditionsfor the practice of environmentally responsible beha-viour in everyday life, they do have an influence onthe acceptance of environmental policy measures.

Diekmann and Preisend .orfer (1992) as well as Franzen(1997) and Kunz (1998) ascertained that persons whosupport environmental policy measures are generallywell informed about environmental issues, whereas thisis not the case with opponents of such measures.However, according to the results of a national surveyconducted in Switzerland, knowledge about ecologicalissues is extremely superficial, despite widespread mediacoverage of issues such as ozone depletion, air pollutionand the greenhouse effect (Diekmann and Preisend .orfer,1992). Only one-third of the Swiss population couldspontaneously name CO2 as the main cause of thegreenhouse effect. Just slightly higher was the percen-tage of people who could give the correct answer to aquestion concerning the ozone problem.2 Furthermore,the subjective assessment of environmental risks by laypeople differs clearly from that by experts (Jaeggi et al.,1996): while consequences of forest decline were rankedhighest by lay people, followed by stratospheric ozonepollution and garbage problems, the greenhouse effectwas ranked lowest, actually half as dangerous asstratospheric ozone pollution. This contradicts theconsequences of climate change forecasted by theexperts. Kempton (1991) as well as Bostrom et al.(1994) studied people’s conception of global climatechange. They found that unknown terms such as‘‘greenhouse effect’’ are interpreted in preconceivedcategories, and often people do not recognise theconnection between their own actions and environmen-tal problems. Kriesi and B .utschi (1998) studied theimpact of press information on the public’s knowledgeand attitudes. As an example of press information, twonewspaper articles were chosen which dealt with someaspects of CO2-related problems. There were indicationsthat the messages received could be interpreted inunanticipated ways: the information that plants growfaster under conditions of higher concentrations of CO2

decreased the urgency of environmental protectionfor some persons. This is due to the fact that anynew information is processed within the context of one’sown existing beliefs, one’s own mental models (Morganet al., 1992).

2.3. Research gap: perceptions on risk assessment

Regarding the significance of risk assessment studiesin the public discussion on environmental problems, aresearch gap exists: first of all, hardly any empiricalstudies on the specific topic ‘‘politicians’ attitudestowards risk assessment studies’’ can be found. Further-more, while abundant research on environmentalawareness and environmental behaviour has been done,

ARTICLE IN PRESS

Fig. 1. Sampling strategies in the social sciences (source Hunziker,

1995).

A. Wallner et al. / Global Environmental Change 13 (2003) 185–194188

only little research exists on the question of how thepublic’s acceptance of environmental policies can beenhanced.

With the present study, we tried to make a first steptowards filling this gap by gaining new insights into howthe results of risk assessments relate to policy makingand opinion formation. In order to obtain this goal, wedeveloped the following research questions:

1. Do results of scientific experiments influence thepoliticians in their readiness to prepare new environ-mental policy measures?

2. Which factors influence the public’s acceptance ofenvironmental policy measures?

3For an explanation of the ICAT project see footnote 1.

3. Methods

3.1. Methodology

In social sciences two different methodologicalapproaches can be used to study public perceptions onvarious issues (Lamnek, 1988). The quantitative ap-proach is used to measure precise answer frequencies, totest hypotheses, and to discover correlations between thevariables. Researchers using the quantitative approachoften work with standardised questionnaires, whichare build upon basic knowledge and already existingtheoretical concepts on the topic of interest. In contrastto the quantitative approach, the qualitative approach(Atteslander, 1991; Filstead, 1971; Lamnek, 1988) isbased on the principle of greatest possible openness andflexibility: any information on the subject—expected ornot—is desirable; new insights that emerge during astudy are allowed to influence the way an ongoing studyis structured. Qualitative methods permit a maximumgain of new insights into a problem; however, they donot allow the evaluation of quantitative frequencies andconduction of statistical testing of hypotheses. In orderto acquire deep insights regarding the goals and researchquestions of this study presented here, we decided to usequalitative methods.

3.2. Data collection

Out of the range of possible qualitative interviewtechniques, the ethnographic interview (Spradley, 1979)was chosen. This interview technique is recommendedwhen the interviewer initially has little understanding oflocal—and in this case of group-specific—concepts(Agar, 1996; Spradley, 1979). In ethnographic interviewsopen-ended questions are used, permitting the infor-mants to structure and define their own responses. Thisis essential for allowing the structure of people’s mentalmodels to emerge and for identifying the set of possiblemisconceptions (Morgan et al., 1992).

All the interviews conducted for this study consistedof three parts:

1. The interviewer asked questions about knowledgeand awareness regarding greenhouse effect and airpollution.

2. The interviewer gave a short presentation of themodel-ecosystem experiments of the ICAT project.3

3. The interviewees were asked for reactions to thepresentation and to possible environmental policyproposals based on the results of such experiments.

3.3. Sampling

The informants were selected according to the‘‘theoretical sampling strategy’’ (Glaser and Strauss,1967; Hunziker, 2000). The principle of this strategy isone of ‘‘maximum variety’’ (Morse, 1994), and notstatistical representativeness. Therefore, a theoreticalsample, also called ‘‘purposeful sample’’ (Patton, 1990),consists of persons with widely differing opinions, which‘‘represent the margin’’ of the sampling universe (Fig. 1).An a priori sample, based on informal expert interviewsand theoretical thoughts was established. A first inter-view was conducted with a person, which was assumedto represent one of the typical positions quite well. Afteranalysing this interview, a next informant, contrastingthe first one as much as possible regarding study-relevantcriteria, was chosen. This sampling procedure wasrepeated until no new positions emerged any more, allassumed positions were covered by at least one interview,and no more new information could be gained from theinterviews. In the course of this study, 15 interviews wereconducted (Table 1). Five of the interviewees aremembers of the Swiss parliament; the others are citizensliving in the city or the surroundings of Zurich.

3.4. Analysis

All interviews were audiotaped and transcribed. Datafor this article is drawn from these verbatim transcripts.

ARTICLE IN PRESS

Table 1

Characterisation of the interviewees

No. Sex Age Education Present occupation

1 F 53 Lawyer Lawyer, member of parliament

2 M 38 Painter, business training Manager, member of parliament

3 M 46 Agronomist Chief of government department, member of parliament

4 M 46 University degree Political scientist, member of parliament

5 M 59 Printer Senior executive officer, member of parliament

6 F 58 Housewife

7 M 57 Foreman Site manager

8 F 41 Secretary Housewife, art dealer

9 F 45 University degree Journalist

10 M 46 Teacher Teacher and ecological consultant

11 M 64 Restauranteur Restauranteur

12 M 48 Bank employee Bank employee

13 M 27 University degree Unemployed

14 M 36 University degree Unemployed

15 M 36 Farmer Farmer and truck driver

4We combine the presentation of the results with the discussion,

because interpretation is the chief component of the results of studies

conducted with the aid of qualitative research methods.

A. Wallner et al. / Global Environmental Change 13 (2003) 185–194 189

The contents of the interviews were investigatedaccording to a method based on the ‘‘GroundedTheory’’ of Glaser and Strauss (1967):

1. In a first step (open coding), the full text was screenedsection by section in order to identify noticeablestatements regarding (a) greenhouse effect and airpollution and (b) reactions to the presented model-ecosystem experiments and possible environmentalpolicy proposals. Similar statements were assigned tocategories, which were defined primarily according tothe empirical data as well as due to the researchquestions. The following interviews were then ana-lysed in the same way, however, based on the alreadyestablished set of categories, which were, of course,revised, refined and enlarged according to theempirical findings.

2. In a second step (axial coding), categories thatshowed to be dominant—so-called key-categories—were crosschecked with the aid of the remainingcategories in order to detect the interrelationshipsbetween them.

3. In a final step (selective coding), the interviews werescreened again for finding contributions that furtherdifferentiate the key categories and their interrela-tionships.

The special software NUD�IST (non-numerical un-structured data indexing searching and theorizing)(Richards and Richards, 1994) was used for thisanalysis.

The following results show which opinions regardingpublic expectations towards science principally exist. Inparticular, the quantitative weight of the detectedopinions remains unknown. In order to emphasise thevalidity of the results and to illustrate the findings,translated quotations (in italics) from the original

interviews are added (the numbers correspond to theinterviewee’s number in Table 1).

4. Results and discussion4

4.1. Politicians’ expectations of science

After a short presentation of the model-ecosystemexperiments of the ICAT project, the interviewedpoliticians were asked what they thought of theseexperiments and if they would rely on the results ofrisk assessments in political debates on environmentalpolicy. Analysis of these interviews showed that threebasic attitudes towards the role of scientific studies inthe discussion on environmental problems could bedistinguished. Those three basic attitudes can bedescribed as follows:

Attitude 1: Studies in natural science provide clearresults, which are a prerequisite for a political impulsefor change. By informing the public about environ-mental problems and explaining the sense of environ-mental policy measures, natural science supportspoliticians in the implementation of measures.

When proposing protection measures politicians might

have to propose certain restrictions and inconveniences.

It is completely natural to only accept measures whose

meaning one understands. And if the meaning is to

reduce a problem with our forests, with the atmosphere

and with everything that is connected to the CO2

problem, this can be illustrated with such scientific

findings. (1)

ARTICLE IN PRESSA. Wallner et al. / Global Environmental Change 13 (2003) 185–194190

Attitude 2: As an early warning system, naturalscience perceives developments and points them outand thus provides an important contribution to theoverall judgement of a problem. However, in discussionson specific protection measures, factors other thanscientific results are taken into account.

Experiments in natural science can help to de-

emotionalise the discussion on environmental problems.(y) Those findings are a piece of the whole puzzle in

the overall judgement but they play a marginal role in

discussions on specific protection measures. (y) A

certain effort of observation and documentation is

simply necessary to be able to justify protection

measures and also to think ahead in the sense of an

early warning system. (3)

Attitude 3: Natural science practices basic researchbut plays a marginal role in the political discussion onenvironmental problems.

Basic research is ok; it’s ok that we acquire more

knowledge. Certain insights will be gained from such

studies and they might be developed even further. (y)But using those results in the discussion on environ-

mental problems does not help us much. (2)

If we now look at Knoepfel’s argument of sciencebeing given too much political responsibility (Knoepfel,1992) in the light of our findings, we can say: If allpoliticians held attitude 3—saying that scientific findingsonly play a marginal role in policy formation—therewould be no danger of science taking over too muchpolitical responsibility. This danger would exist if mostpoliticians held attitude 1.

If we compare the basic attitudes of politicianstowards science found through our in-depths interviewswith the general description of the four functions ofscience by Freiburghaus and Zimmermann (1985), thefollowing can be stated: In attitude 1 all four functionsof science are present, while in attitude 2 probably threeto four functions exist, and in attitude 3 science is justattributed an instrumental function.

According to Cohen (1997), a nationwide survey ofUS state legislators and their staff revealed a strongsupport for the use of risk assessment. If in our studymost politicians held the first or the second attitude, riskassessment would play an important role in decisionmaking, and therefore our findings would be consistentwith the findings of the survey Cohen reports. However,since our study was conducted with in-depth qualitativeinterviews exclusively, we cannot make any statementsabout the percentage of politicians holding the differentattitudes. Nevertheless, based on our qualitative inter-views we can say that those politicians holding the firstor second attitude are generally interested in informa-tion on risk assessments, but they often do not getsufficient information. The interviewees mentioned that

they would appreciate better, that means more, betterunderstandable, more precise and more easily availableinformation from science than has been the case so far.Whereas articles in scientific journals are the mostcommon way for scientists to publish their findings,politicians do not consult such articles. No matter whichway is chosen to inform politicians about scientificstudies—be it for example newspaper articles, hearings,direct conversations with individuals—the informationhas to be understandable. Or as Pielke (1994) puts it:politicians ‘‘need a message, not data’’. This leads to thequestion as to who should mediate the information ofscientific studies and their results. Since this question isalso important in correspondence with the public’sattitude towards scientific studies, this question will bediscussed later.

4.2. The public’s acceptance of environmental policy

measures

Analysis of the interviews led to the hypothesis thatthe public’s acceptance of environmental policy mea-sures is affected by perception, knowledge and degree ofconstraint by such measures.

4.3. Direct perception

One of the key factors affecting the public acceptanceof environmental policy measures is perception. Personaldirect perception of environmental pollution and itsimpacts—i.e. to see or feel those impacts—seems toenhance the readiness to support environmental protectionmeasures. That is to say, only those who directly perceiveenvironmental problems and their impacts in this way andrecognise those problems and impacts as such understandthe importance of environmental policy measures andtherefore are more likely going to accept such measures.

This can be illustrated with the findings of theinterviews. When talking about ozone, people seem toconfuse stratospheric ozone depletion with troposphericozone pollution. However, they know that ozonepollution as well as the destruction of the ozone layercan have adverse health effects. The interviewees assumeheadache, watering eyes and breathing problems to beconnected with ozone and many feel themselves or afamily member to be affected by health problems causedby ozone. Therefore, the issues concerning ozone areperceived as a real threat:

Ozone is something one can really feel. I mean, I have

the feeling that the symptoms I just named, that is

problems with breathing, headache and so on, they are

felt relatively fast. (12)

Everyday Swiss newspapers publish a short bulletinabout the expected concentrations of pollutants for theday as well as a short overview of the pollutants’

ARTICLE IN PRESSA. Wallner et al. / Global Environmental Change 13 (2003) 185–194 191

concentration in various areas of Switzerland on thepreceding day. According to the interviewees, these figuresdo not receive much attention by the public. The feelingof being personally affected by high ozone concentrationsseems to weigh more, as one informant said:

If you feel the impacts personally that is much more

intensive than if you read it as a simple figure in the

daily press. (13)

Those informants who think they can directly perceivethe effects of ozone are willing to support air pollutioncontrol measures. Even those who do not feel directlyaffected said in the interviews that if they had healthproblems and saw a connection between their healthcondition and ozone, they would more likely support airpollution control measures.

The situation is different with the topic of CO2: laypeople tend to be unaware of the connection betweenCO2 and the greenhouse effect. The consequence of thisunawareness is that elevated CO2 concentrations are notperceived as a possible threat. Furthermore, peoplecannot see or feel the impacts of the greenhouse effectdirectly, and therefore it is not perceived as a real threat.The finding that lay people perceive the greenhouseeffect not really as a threat is supported by the study ofJaeggi et al. (1996) on people’s assessment of environ-mental risks. As long as something is not perceived as athreat, there is no reason why someone should be willingto support measures to reduce a non-existing threat. AsKunz (1998) said, the conception of natural risks isclosely related to the experience and the personalobservation. Therefore, natural disasters play a decisiverole in the decision process for the benefit of concreteprotection measures. It can be concluded that if it waspossible to mediate this perception to the people, theirreadiness to support environmental policy measurescould be enhanced.

4.4. Knowledge of a problem

According to our interviews, knowledge also plays animportant role in whether people accept environmentalpolicy measures or not. When people are asked whatthey know about the greenhouse effect, the answers tosuch a question can be classified in three categories:

1. The person is well informed about the topic.2. The person has little or no knowledge about the

topic.3. The person confuses this with other topics.

It is this third category of answers, which is mostinteresting here. The following two examples taken fromthe interviews illustrate this category:

The greenhouse effect is threatening. I can experience

this in the sun and I have the feeling that this is

connected with ozone, with the greenhouse effect

because the sun is so much more aggressive than it

used to be. (6)

We’ve had good examples of the greenhouse effect this

summer, with these very strong heat waves. (...)Another very good example is the fact that diseases

of the respiratory tract are increasing. (7)

It would be wrong to say that these informants donot have knowledge about the greenhouse effect. Theyhave heard about the greenhouse effect but they confuseit with temperature variations, ozone depletion andozone pollution. These findings correspond with thestudies by Kempton (1991) and Bostrom et al. (1994).People giving such answers have heard about thegreenhouse effect but their knowledge about it isincomplete. Therefore, they interpret the term ‘‘green-house effect’’ in terms of pre-existing categorieslike ozone depletion, ozone pollution and personallyexperienced temperature variations. According to Diek-mann and Preisend .orfer (1992), Franzen (1997) andKunz (1998), people who are generally well informedabout environmental issues support environmentalpolicy measures. Thus, it is important to clarify suchfallacies.

4.5. Degree of constraint

Even when people know about environmental pro-blems and their impact and perceive them as a realthreat, they do not necessarily support environmentalpolicy measures, as the following quotation from aninterview shows:

Yes, I would support measures to reduce CO2-emissions if they are reasonable and I had the feeling

that they would be successful. (...) But I think, there we

are dependent on science, which can emphasise some-

thing plausibly and also prove it. (12)

This reaction is due to the often deeply intrusivecharacter of such measures. The less constraining ameasure is, the more likely it is to be accepted (Kriesiand B .utschi, 1998). Measures such as a raise in the priceof gasoline or a speed limit of 100 km/h on nationalhighways impinge more directly than measures such astechnical improvements of cars. This is because theformer are designed to render the use of private carsmore expensive or to restrict it to the purely essential,whereas the latter do not restrict the actions ofindividuals. If a measure is very intrusive, people wantto be sure that it and its concomitant are worth it andtherefore ask science to prove the effectiveness ofprotection measures.

ARTICLE IN PRESSA. Wallner et al. / Global Environmental Change 13 (2003) 185–194192

4.6. Mediation

If environmental problems and their impacts are noteasily perceivable by lay people—as is the case withCO2—this perception has to be mediated. The analysisof the interviews showed that experiments such as theones with model-ecosystems could be used for themediation of the impacts of higher CO2 concentrationson forests. Although some of the intervieweeswere doubtful whether the results obtained throughthe experiments on the model-ecosystems would be thesame as in experiments in real forests, the experimentsseem to offer good possibilities for illustrating theimpacts of environmental pollution or greenhouse effectto lay people. During the interviews, pictures of leaves ofbeech trees that had been grown in chambers withdifferent CO2 concentrations were used to explain theimpact of higher CO2 levels on plants. Those pictureswere highly appreciated by the interviewees since theycould directly see the impact of elevated CO2:

It is obvious, these pictures show that those leaves

are not the way they should be, it looks as if they were

sick. (7)

If people are not informed about the linkages betweenthe greenhouse effect and CO2 and therefore opposeenvironmental measures, their knowledge about envir-onmental problems and possible impacts should beenlarged. Information is an essential prerequisite forindividuals to assume responsibility (Kunz, 1998).However, mediating information is not an easy task.Information can easily be interpreted in unanticipatedways and lead to unexpected consequences. In theinterviews, when told that spruce responded positively ingrowth to CO2 enrichment one informant said:

This is interesting. 15 years ago, when everybody

talked about ‘‘forest decline’’ it was said that spruce

has been damaged. (...) So this is actually positive if

spruce is now developing well under higher concentra-

tions of CO2, right? (15)

Information can be interpreted in unanticipated waysand thereby decrease the urgency of environmentalprotection in the view of some people. Furthermore, ithas to be remembered that people conceptualise newinformation in pre-existing terms. This is what Morganet al. (1992) meant when saying that any new informa-tion is processed within the context of one’s own existingbeliefs, one’s own mental models. If there is nopreliminary knowledge about a topic, a new messagewill be incomprehensible, or if people already haveerroneous beliefs, the new information might bemisconstrued (Morgan et al., 1992, p. 2050). This issupported by Petty and Cacioppo (1986), who arguethat attitudes can only be changed through themediation of knowledge if the addressed people already

have a preliminary understanding of the aspiredattitude. If this is not the case, the mediation ofknowledge is counterproductive, because the newlygained knowledge animates people to intensify theirexisting position through the development and strength-ening of counter-arguments.

Therefore, much attention has to be paid to the way inwhich information is mediated: ‘‘Communicators needto know the nature and extent of a recipient’s knowledgeand beliefs if they are to design messages that will not bedismissed, misinterpreted, or allowed to coexist withmisconceptions’’ (Morgan et al., 1992, p. 2050). Or asRebetez puts it: ‘‘Effective transfer of scientific informa-tion can only be achieved if scientists are conscious ofcertain biases in the public’s conceptions of climate andif they take the public’s expectations into consideration’’(Rebetez, 1996, p. 496).

5. Conclusion

This study focussed on the role of a specific type ofrisk assessment study in policy making and opinionformation. The study confirms the findings of otherstudies regarding people’s assessments of environmentalrisks as well as the close relation of the conception ofnatural risks and the personal observation and experi-ence of that risk. In addition, the study reveals specificresults regarding public opinions on natural scienceexperiments and shows that the use of model-ecosystemexperiments in explaining scientific information canpresent a new possibility to enhance the public’sacceptance of environmental policies. Furthermore, thisstudy is one of the few existing empirical studies on thequestion of politicians’ attitudes towards risk assessmentstudies and therefore provides specific results regardingthe topic of risk assessment and policy making. Andfinally, the results reveal the importance of a mentalmodels approach towards risk communication. Thus,the aims of our study, namely to fill some of the mostrelevant research gaps regarding the significance of riskassessment studies in the public discussion on environ-mental problems have been reached. In particular, theresearch questions can be answered as summarised inthe following statements, which represent the condensedessence of the findings from our qualitative interviews.

5.1. Risk assessment and policy making

The question whether the results of scientific experi-ments influence politicians in their readiness to preparenew environmental policy measures can be answered bystatement 1:

It is the decision-maker’s general attitude towards

science, which defines his or her readiness to change

ARTICLE IN PRESSA. Wallner et al. / Global Environmental Change 13 (2003) 185–194 193

existing or to formulate new environmental policies

relying on new scientific findings.

When looking at the relevant literature concerningscience and politics, we pointed out that there is adiscussion on how much political responsibility scienceshould have. Consequentially, our findings resulted instatement 2:

The politicians’ attitude towards science in general

determines how much political responsibility is given to

science.

Based on our findings we can state that the morefunctions a decision-maker attributes to science, themore he/she will rely on scientific results in formulatingenvironmental policies. As mentioned before, the state-ments have a hypothetical character. In particular, wecannot make any comments about the percentage ofpoliticians holding the three detected attitudes at thispoint. Since the results of our study suggest that theattitudes of decision-makers are crucial to the readinessto formulate environmental policies, a quantification ofhow many politicians are holding the three detectedattitudes should be done by applying quantitativemethods to the research question.

5.2. Risk assessment and public acceptance of

environmental policies

Regarding the public’s acceptance of environmentalpolicies, the results of our study lead to statement 3:

Direct perception—i.e. seeing or feeling—environmen-

tal problems and their impacts can increase the

acceptance of environmental policy measures by the

public.

Of course it is difficult to perceive the impacts ofglobal climate change directly. Therefore, it is importantthat scientists try to mediate this perception to thepublic. From the results of our study it can be concludedthat model-ecosystem experiments can support suchmediation since different scenarios of the same risk canbe demonstrated on a small area. For example, in theexperiments considered in our study, the observers wereenabled to directly see the influence of different CO2

concentrations on model forests. In this way, theeffectiveness of policy measures such as the enforcedreduction of CO2 concentrations can be demonstrated tothe public. Unfortunately, the use of model-ecosystemexperiments in information campaigns might oftennot be possible due to the enormous costs of suchexperiments.

While various empirical studies have shown adiscrepancy between environmental knowledge andenvironmental behaviour (Diekmann and Preisend .orfer,

1992; Jaeger et al., 1993), based on our results we canformulate statement 4:

Better environmental knowledge enhances people’sreadiness to accept environmental policy measures.

The problem here is that people often confuseinformation about various environmental topics. Asolution to solve this problem is to make sure that—when communicating scientific information to laypeople (be it politicians or the public)—the informationhas to be easy-to-understand for non-experts and thewording of the information has to fit the target group.However, if scientists want to be sure that theirinformation will not be dismissed, misinterpreted orcoexisting with misconceptions, they have to know thenature and extent of the recipients’ knowledge andbeliefs. Recognising the fact that new information isprocessed within the recipient’s own mental models,means that communicating information has to becarried out very seriously. Thus, careful empiricalresearch is often required that allows taking intoaccount existing mental models. Scientific informationregarding environmental risks and possible policiescould then be formulated more concisely towardsdifferent target groups considering their specific mentalmodels.

References

Agar, M., 1996. The Professional Stranger. Academic Press, San

Diego.

Atteslander, P., 1991. Methoden der empirischen Sozialforschung.

Walter de Gruyter, Berlin.

Blaikie, P., 1995a. Changing environments or changing views?

Geography 80, 203–214.

Blaikie, P., 1995b. Understanding environmental issues. In: Morse, S.,

Stocking, M. (Eds.), People and Environment. UCL Press,

London, pp. 1–30.

Bostrom, A., et al., 1994. What do people know about global climate

change? 1. Mental models. Risk Analysis 14, 959–970.

Brunold, C., et al., 2000. Wald und CO2. Ergebnisse eines .okologische

Modell .okosystemversuchs. Haupt, Bern.

Clark, W.C., Majone, G., 1985. The critical appraisal of scientific

inquiries with policy implications. Science, Technology & Human

Values 10, 6–19.

Cohen, N., 1997. The politics of environmental risk: perceptions of

risk assessment in the state legislatures. Policy Studies Journal 25,

470–484.

Cotton, W.R., Pielke, R.A., 1992. Human Impacts on Weather and

Climate. ASTeR Press, Fort Collins.

Dawes, R., 1980. Social dilemmas. Annual Review of Psychology 31,

169–193.

Diekmann, A., Preisend .orfer, P., 1992. Pers .onliches Umweltverhalten:

Diskrepanzen zwischen Anspruch und Wirklichkeit. K .olner

Zeitschrift f .ur Soziologie und Sozialpsychologie 44, 226–251.

Filstead, W.J., 1971. Qualitative Methodology—First Hand Involve-

ment With the Social World. Markham, Chicago, p. 352.

Foppa, K., Tanner, C., 1995. Wahrnehmung von Umweltproblemen.

In: Diekmann, A., Franzen, A. (Eds.), Kooperatives Umwelthan-

deln. Verlag R .uegger, Chur, Z .urich, pp. 113–132.

ARTICLE IN PRESSA. Wallner et al. / Global Environmental Change 13 (2003) 185–194194

Franzen, A., 1997. Umweltbewusstsein und Verkehrsverhalten. Verlag

R .uegger AG, Chur, Z .urich.

Freiburghaus, D., Zimmermann, W., 1985. Wie wird Forschung

politisch relevant? Haupt Verlag, Bern.

Glaser, B.G., Strauss, A.L., 1967. The Discovery of Grounded

Theory—Strategies for Qualitative Research. Aldine de Gruyter,

New York.

Grob, A., 1991. Meinung—Verhalten—Umwelt. Peter Lang, Bern.

Haas, P.M., et al., 1993. Institutions for the Earth: Sources of Effective

International Environmental Protection. MIT Press, Cambridge.

Hunziker, M., 1995. The spontaneous reafforestation in abandoned

agricultural lands: perception and aesthetic assessment by locals

and tourists. Landscape and Urban Planning 31, 399–410.

Hunziker, M., 2000. Einstellungen der Bev .olkerung zu m .oglichen

Landschaftsentwicklungen in den Alpen. Eidg. Forschungsanstalt

WSL, Birmensdorf.

Jaeger, C., et al., 1993. Determinants of environmental action with

regard to climatic change. Climatic Change 23, 193–211.

Jaeggi, C., et al., 1996. Was uns vom umweltverantwortlichen Handeln

abh.alt. In: Kaufmann-Hayoz, R., Giulio, A.D. (Eds.), Umwelt-

problem Mensch—Humanwissenschaftliche Zug.ange zu umwelt-

verantwortlichem Handeln. Haupt, Bern, pp. 181–196.

J.ager, J., et al., 2001. Knowledge and action: an analysis of linkages

among management functions for global environmental risks.

In: The Social Learning Group (Ed.), Learning to Manage Global

Environmental Risks. MIT Press, Cambridge, pp. 165–178.

Kempton, W., 1991. Lay perspectives on global climate change. Global

Environmental Change, 183–208.

Kley, J., Fietkau, H.J., 1979. Verhaltenswirksame Variablen des

Umweltbewusstseins. Psychologie und Praxis 23, 13–22.

Knoepfel, P., 1992. Zur unzumutbaren politischen Rolle der Natur-

wissenschaften in der Umweltdebatte. GAIA 1, 175–180.

Kriesi, H., B .utschi, D., 1998. Opinion formation and change. The case

of the Swiss policy against air pollution caused by cars, University

of Geneva.

Kunz, P., 1998. Wahrnehmung von Naturgefahren und Naturrisiken.

In: Bader, S., Kunz, P. (Eds.), Klimarisiken—Herausforderung f .ur

die Schweiz. vdf Hochschulverlag, Z .urich, pp. 259–294.

Lamnek, S., 1988. Qualitative Sozialforschung—Bd. 1, Methodologie.

Psychologie Verlags Union, M .unchen, Weinheim.

Landolt, W., et al., 1997. Effects of elevated CO2 concentration and N

deposition on spruce-beech model ecosystems. In: Mohren, G.M.J.,

et al. (Ed.), Impacts of Global Change on Tree Physiology and

Forest Ecosystems. Kluwer Academic Publishers, Dordrecht,

pp. 317–324.

Laurence, L.E., 1978. The question of relevance. In: Laurence, L.E.

(Ed.), Knowledge and Policy: Uncertain Connection. National

Academy of Sciences, Washington.

Litfin, K., 1994. Ozone Discourses: The Politics of Science in

International Enviornmental Negotiations. Columbia University

Press, New York.

Morgan, G., et al., 1992. Communicating risk to the public.

Environmental Science & Technology 26, 2048–2056.

Morse, J.M., 1994. Designing funded qualitative research. In: Denzin,

N.K., Lincoln, Y.S. (Eds.), Handbook of Qualitative Research.

Sage, Thousand Oaks, pp. 220–235.

Patton, M.Q., 1990. Qualitative Evaluation and Research Methods.

Sage, Newbury Park, CA.

Petty, R.E., Cacioppo, J.T., 1986. Communication and Persuation.

Central and Peripheral Routes to Attitude Change. Springer,

New York.

Pielke, R.A.J., 1994. Scientific information and global change policy-

making. Climatic Change 28, 315–319.

Rebetez, M., 1996. Public expectation as an element of human

perception of climate change. Climatic Change 32, 495–509.

Richards, T.R., Richards, L., 1994. Using computers in qualitative

research. In: Denzin, N.K., Lincoln, Y.S. (Eds.), Handbook of

Qualitative Research. Sage Publications, Thousand Oaks/London/

New Dehli, pp. 445–462.

Rowlands, I.H., 1995. The Politics of Global Atmospheric Change.

Manchester University Press, Manchester.

Segerson, K., 1992. The policy response to risk and risk perceptions.

In: Bromley, D.W. (Ed.), The Social Response to Environmental

Risk. Kluwer, Boston, pp. 1001–1130.

Smith, V.K., 1992. Environmental risk perception and valuation:

conventional versus prospective reference theory. In: Bromley,

D.W. (Ed.), The Social Response to Environmental Risk. Kluwer

Academic Publishers, Boston, pp. 23–56.

Spradley, J.P., 1979. The Ethnographic Interview. Holt, Rinehart and

Winston, New York.

The Social Learning Group, 2001. Learning to Manage Global

Environmental Risks. MIT Press, Cambridge.

Urban, D., 1986. Was ist Umweltbewusstsein? Zeitschrift f .ur

Soziologie 15, 363–377.