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Primary School Teachers'Understanding ofEnvironmental Issues: Aninterview studyMike Summers , Colin Kruger , Ann Childs &Jenny MantPublished online: 02 Jul 2010.
To cite this article: Mike Summers , Colin Kruger , Ann Childs & Jenny Mant(2000) Primary School Teachers' Understanding of Environmental Issues:An interview study, Environmental Education Research, 6:4, 293-312, DOI:10.1080/713664700
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Environmental Education Research, Vol. 6, No. 4, 2000
Primary School Teachers’ Understanding of
Environmental Issues: an interview study
MIKE SUMMERS, COLIN KRUGER & ANN CHILDS Oxford UniversityDepartment of Educational Studies, Oxford, UK
JENNY MANT Oxford Brookes University, Oxford, UK
SUMMARY In the light of an increased emphasis on environmental education inrevisions of the National Curriculum to be introduced in September 2000, this studyused in-depth interviews to explore the understanding of a non-random sample of 12practising primary school teachers in four areas: biodiversity, the carbon cycle, ozone andglobal warming. A methodological innovation in this research was the prioridenti® cation of basic scienti® c explanations of each area for a primary teachers, and theuse of these as benchmarks for judging understanding. The study was able to identifythose underpinning science concepts which were well understood, and those which werenot so well understood. Some missing concepts and misconceptions are also reported.Although the ® ndings cannot be generalised to all primary teachers, the fairly strongscience backgrounds of eight teachers in the sample suggest that some of the dif® cultiesreported may be found more widely. It is suggested that both the basic explanations andthe dif® culties of understanding displayed by the teachers can usefully inform pro-grammes of professional development for environmental education. An outline of a guidefor teacher education adopting this approach is provided.
Introduction
Context and Purpose
Education about the environment is about to receive a major boost in primaryand secondary schools in England and Wales following revisions of the NationalCurriculum to be implemented in September, 2000 (Quali® cations and Assess-ment Authority, 1999). A substantially increased emphasis on the environmentand sustainable development is evident not only in science and geography,but is now also a prominent feature in a revised introduction to the wholecurriculum.
ISSN 1350-4622 print; 1469-5871 online/00/040293-20 Ó 2000 Taylor & Francis Ltd
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It is easy to assume that when new curricular material is introduced teachersare well equipped to teach it. But is this the case for environmental issues andsustainable development in primary schools? We have argued on many occa-sions that good subject knowledge is essential for the best teaching (e.g.Summers, 1994; Summers & Mant, 1995). However, little is known aboutprimary teachers’ current knowledge of these issues.
The goals of the work described below were to: (a) explore in some detail theexisting understanding of a number of environmental issues displayed byprimary teachers; and (b) use the ® ndings to inform the production of a guideto help teachers develop a more scienti® c perspective. An integral part of theresearch was a critical consideration of what might constitute an appropriatelevel of understanding for a primary teacher. This article will show how wegrappled with this problem, as well as describing the outcomes of the research.
Environmental Education and Sustainable Development
An increased recognition of the importance of education for sustainable develop-ment provides an important reason for developing children’s understanding ofenvironmental issues. The concept of sustainable development is, of course,multifaceted and involves environmental, economic and social consequences ofMan’s activities. However, the whole rationale underpinning arguments forsustainable development is the prevention of damage to the environment. Thisis re¯ ected in the de® nition of the purpose of education for sustainable develop-ment in the schools sector provided by the Council for Environmental Education(1998):
Education for sustainable development enables people to develop theknowledge, values and skills to participate in decisions about the waywe do things individually and collectively, both locally and globally,that will improve the quality of life now and without damaging theplanet for the future.
Hence we see sustainable development and environmental concerns asinextricably linked: education about the former is intimately bound up withconsideration of the latter, and our research informs both.
Scope
We readily endorse a view of education for sustainable development, such asthat given above, which emphasises the three dimensions of knowledge, valuesand skills (for example, of decision-making). Our own focus on teacher knowl-edge in the present research is clearly just one aspect of what will be requiredto help pupils develop their learning in these three dimensions. However, andas we said above, it is our view that secure teacher knowledge (which in thisarticle is taken to include understanding) is a prerequisite for the most effectiveteaching.
A further restriction is our concentration principally on scienti® c knowledge, tothe exclusion of very important geographical and cross-curricular perspectives.To some extent this re¯ ects our own research tradition and expertise (scienceeducation). But it also stems from a belief in the centrality of science in
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Understanding Environmental Issues 295
understanding and making appropriate decisions about the environment. Theimportant role of accurate scienti® c knowledge in teaching and learning aboutthe environment has been argued in some detail by other writers in this journal(see, for example, Boyes et al., 1995).
It should, however, be emphasised that we do not see the development ofteachers’ scienti® c knowledge as a panacea that will somehow revolutioniseteaching and learning about the environment and sustainable development.Rather, it is regarded as just one element (albeit a very important one) of thecomplex knowledge base that should inform teaching in these areas. Further-more, our emphasis on subject knowledge should not be interpreted as in anyway denying the pivotal role of pedagogical knowledge in effective teaching andlearning. We have written before on the distinction between subject knowledgeand pedagogical knowledge (Summers et al., 1998) and the vital importance ofthe latter. The way the present work will be developed to take account of thesebroader concerns is picked up towards the end of this article.
The Areas and Issues Explored
The research focused on understanding in seven areas: biodiversity, the carboncycle, global warming, ozone, energy sources, life-cycle analysis (of a manu-factured product), and sustainability. Each of the areas, except the carbon cycle,can be formulated in terms of an environmental issue. We use the word issue’to mean that which generates a concern and is at least potentially problematicfor the environment. The carbon cycle was included as an area for researchbecause a good understanding of it is a necessary prerequisite for a scienti® cunderstanding of many environmental concerns.
The way in which the issues were formulated is described later. For grammat-ical convenience we will at times refer to all seven areas as issues, but thedistinctive nature of the carbon cycle should be kept in mind.
The work was carried out in two phases: Phase I covered biodiversity, globalwarming, the carbon cycle and ozone, and Phase II the remaining three areas.This was an extensive programme of research and there is insuf® cient space ina single article to report all of the ® ndings. Hence the focus here will be on thePhase I areas.
Previous Work
A search of the research literature has uncovered no investigations of practisingprimary teachers, understanding of environmental issues and sustainable devel-opment. However, we did ® nd two studies of trainee primary teachers. Dove(1996) used a questionnaire survey to investigate the understanding of 60trainees in three areas: the greenhouse effect, ozone layer depletion and acidrain. Boyes et al. (1995) studied aspects of understanding of the ozone layer onlybut with a much larger questionnaire survey of 453 trainees. In the case of ozone,both studies found that trainees were aware of the function of the ozone layerin relation to its ® ltering effect of UV light, the consequent harmful effects whenthe ozone layer is depleted and the role of CFCs in ozone depletion. Boyes et al.,also showed that the trainees were well informed about the location and thenature of the ozone layer. However, both studies found that trainees harbour
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notable misconceptions. For example, many trainees thought that vehicle emis-sions were responsible for ozone depletion. Boyes et al., report that radioactivityand acid rain were also thought to be responsible. Both studies revealed afurther commonly held misconception: that `holes’ in the ozone layer are a directcause of global warming.
In the case of the greenhouse effect, Dove found that the trainees weregenerally familiar with the term itself but had little awareness of the conceptsinvolved. They were aware, for example, of carbon dioxide as an importantgreenhouse gas but had little awareness of other greenhouse gases and werelargely unaware of the natural greenhouse effect. As mentioned above they alsoheld the common misconception that `holes’ in the ozone layer are a direct causeof global warming. Turning to acid rain, most trainees had an awareness thatburning coal was responsible, but their knowledge of the speci® c gases involvedwas low. They were also aware of some of the effects of acid rain, such asincreased weathering of rocks, but did not understand the reasons for this. Inaddition, although they knew forests in Scandinavia had been damaged by acidrain, they were again unable to explain the causes.
The present research therefore contributes to knowledge in two ways: (a) byextending the coverage to new aspects of environmental issues; and (b) byextending the sparse amount of previous work carried out with trainee primaryteachers to experienced practitioners. A distinctive feature of our research is theuse of in-depth interviews rather than survey questionnaires. In addition, thereis a methodological innovation in that benchmarks for understanding each issuewere de® ned at the outset of the research and used as a framework for analysingthe data (see below).
Scienti® c Understanding
At the outset of the research, the team had to decide what might constitute anappropriate understanding of the science of these areas for a primary teacherand, for all except the carbon cycle, specify the issues involved. Drawing uponan approach used successfully in an earlier study (Summers & Kruger, 1994) abasic explanation was constructed for each of the seven areas. This consistedof a number of component statements (explanation components or ECs)which when read in sequence, both provided an explanation of the area and,where appropriate, de® ned the issue. These basic explanations were used asbenchmarks against which understanding was judged.
The explanation components for biodiversity, the carbon cycle, ozone andglobal warming are given in the Appendix. For reasons of space, these are theonly four topics reported in the present article.
The process of devising these basic explanations went through several stages.Initially, the four team members (all science graduates) researched the areas andproduced explanations at their own level. Then over a series of meetings theseexplanations were compared, combined and simpli® ed to try to capture just theessential ingredients of each.
It must be emphasised that these explanations represent no more than ourown shared and distilled professional judgements of what might be appropriatefor primary teachers, and we claim no status for them beyond this. However, itdoes seem that we can claim originalityÐ a search of the literature has failed to
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Understanding Environmental Issues 297
uncover any other explicit attempts to de® ne understanding of these issues forprimary teachers.
Methodology
Overview
This was a qualitative interview study of 12 practising primary school teachers.The goals of the interviews were to:
1. explore each teacher’s understanding of the issues as de® ned by theexplanation components.
2. identify areas of partial understanding and misconceptions.
Sample
The 12 primary teachers were interviewed about their understanding of the fourenvironmental issues covered in Phase I of the research. These teachers consti-tuted an opportunity sample of volunteers (10 women and 2 men) working inseven different state primary schools. The teaching experience representedranged from 1 to 20 years. Six of the teachers reported studying science as a`main subject’ during their initial teacher training, while eight had A-levelscience quali® cations (biologically based, except for one in each of chemistry andenvironmental science). Hence the sample had quite a strong science back-ground and this may account for a willingness to volunteer for the presentstudy.
Interview studies provide an opportunity for gathering data of more certainvalidity than that collected from questionnaire surveys. However, since this wasnot a random sample, the ® ndings cannot be generalised to all primary teachers.Although small, the number of teachers interviewed is large enough for numeri-cal trends to be of interest. Given the science bias of the sample, it may beexpected that indications from this group will over estimate the understandingpresent in the broader community of primary teachers. We pick up this pointtowards the end of the article.
The Interviews
The teachers’ understanding of each of the four issues was probed by means offour drawings (one per issue). Each drawing depicted an aspect of the issueunder investigation. Underneath this was a single open question of the form`does this picture suggest to you any ideas about the issue of global warming?’(for example), followed by a number of very speci® c statements. These latterstatements were designed to cover all of the ECs for the targeted issue, andhence ensure coverage in terms of the explanation to be used as the benchmarkfor understanding. For example, the situation, open questions and statementsused for global warming are shown in Fig. 1. The right-hand column (forresearch team use only) shows how the speci® c statements were mapped on tothe explanatory components e.g. GW4, GW6 means that this statement was usedto probe the teachers’ understanding of global warming components 4 and 6.
Initially, the speci® c statements were covered up and the conversation was
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GLOBAL WARMING
In the ® rst picture, a gardener has left the comfort of his coal ® re indoors to tend young plantswhich are growing under glass. The second picture shows a typical British high street duringa heat wave.
Mapping
Do the pictures suggest to you any ideas about the issue of global warming? ALL22. The process by which the glass keeps the seedlings warm is different from
the way the gardener’s coat keeps him warm. GW123. The Sun’s increasing strength making the Earth warmer will be good for GW2a
us all. GW2b,724. Without one particular gas in the atmosphere, the whole planet would GW3
be colder. GW4 ,525. All the energy the Earth gets from the Sun is retained by the planet
and its atmosphere. GW626. The gardener should plant trees to counteract the effect of his coal ® re on
the atmosphere. GW627. The electricity supply to the gardener’s home could contribute to global
warming. GW8, 928. Because the Earth’s temperature has ¯ uctuated naturally in the past, there
is no need to worry about the present increase in average globaltemperatures. GW2a, 2b, 10
FIG. 1. The situation, open question and statements used to investigate teachers’ ideas aboutglobalwarming.
initiated using the open-ended question. The interviewer’s role here was non-leading and used prompts such as `what do you mean by that?’, `can you tell memore about that?’, and so on.
Following this open-ended phase (typically taking 5 minutes) teachers wereasked to respond true, false, don’t understand or not sure to the ® rst of the speci® cstatements, and were then prompted to explain verbally their reasons for theresponse. This was repeated for each statement in turn. It must be stressed thatthe raw responses were not used for the analysis: their purpose was solely toinitiate a conversation during which the interviewer probed the reasons for theresponse. It was these reasons that were used to make judgements aboutunderstanding.
Interviews took place in the participants’ schools and lasted (typically) for justunder an hour. All the interviews were tape recorded and fully transcribed.
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Understanding Environmental Issues 299
Analysis of the Interviews
For a given EC, a judgement was made according to whether the elicitedresponse was scienti® c (i.e. the response matched the EC statement), partiallyscienti® c (it displayed a part of the EC statement), non-scienti® c (the knowledgewas incorrectÐ a misconception) or absent (the interviewee seemed to have noknowledge of the EC statement).
Coding of the ® rst two transcripts was carried out by the research of® cer andthe other three members of the research team. Reliability of the analysis wasjudged by comparing the categorisations of the of® cer (who was to go on andanalyse all the transcripts) and the majority categorisation of the other threereaders. Using this comparison, 85% of all categorisations were identical. Hence,we argue that while the ® nal judgements made by the research of® cer are likelyto be consistent, other analysts might make different judgements in a fairly smallproportion of cases. Experience showed that this variation was almost invariablyin distinguishing between what was to count as scienti® c rather than partiallyscienti® c.
In a further stage of analysis, all misconceptions (non-scienti® c views) werelisted and counted.
Results
Presentation
Even though this article covers only the ® rst four issues targeted by the researchprogramme, the dataset is still very large. Hence the strategy used for reportingthe ® ndings is to give a complete description of the ® ndings for one area toillustrate the comprehensive nature of the analysis. For the other three areas themost signi® cant ® ndings from the interviews are collapsed together in a singletable and summarised verbally more brie¯ y.
The number of each Explanation Component referred to in the text is givenin brackets (BD 5 biodiversity, CC 5 carbon cycle, OZ 5 ozone, GW 5 globalwarming). The ECs are listed in full in the Appendix.
Biodiversity
Tables 1a, 1b and 1c summarise the ® ndings from that part of the interview withteachers which dealt with biodiversity. Table 1a shows the 12 ExplanationComponents for biodiversity, which are designated as scienti® c views, and thenumber of teachers who displayed ideas indicating an understanding of each ofthem. Note that the ® gures in brackets are important since they signify thenumbers of teachers displaying no knowledge of an EC (the `absent’ category).Table 1b shows the numbers who had partially scienti® c views, in which onlysome aspects of the ECs were expressed, while Table 1c lists non-scienti® c views(or misconceptions) which differ from the ideas expressed in the ECs.
Scienti® c views. Some scienti® c ideas were understood by many of the inter-viewees while others were less widely understood. For example, eight ofthe teachers interviewed showed awareness that a species is de® ned by itsreproductive isolation from other species (BD1). Nine of the teachers knew that
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TABLE 1a. Scienti® c views of the biodiversity explanation components displayed by 12 primaryteachers (® gures in brackets indicate the number of teachers in which the particular view was not
present at all)
No. ofScienti® c views (i.e. explanation components) teachers
BD1 A species is a group of living things which can breed with each other(and produce fertile offspring). 8
BD2a There is a loss of diversity of species (i.e. the number in existence isgetting less). 9
BD2b This diversity is needed for aesthetic, moral and practical (e.g. bene® cialto Man) reasons. 7 (3)
BD3a There is a loss of the diversity within species. 3 (3)BD3b This diversity (within species) is needed to resist extinction by pests or
disease. 1 (5)BD4 Living things exist in communities made up of many inter-dependent
species linked by a network of relationships e.g. feeding, competition. 12BD5 The living things interact with each other and with their non-living
environment to form a balanced, self-suf® cient unit called an ecosystem ,e.g. a particular woodland, forest, tundra, stream, pond etc. 6
BD6 Most species in the wild can survive only in the conditions pertainingin their particular ecosystem. 6 (3)
BD7 Human activity (e.g. habitat destruction, over-harvesting, pollution,foreign introductions) adversely affects many ecosystems, causingextinction of species and consequent loss of biodiversity. 12
BD8 These lost species cannot be replaced. 11*BD9 All members of a species have the same basic genetic makeup but there
is a diversity due to small variations between individuals. 7BD10 These variations enable some individuals to survive and the species to
adapt to changed conditions (e.g. to resist extinction by new pests ordiseases which kill the restÐ see 3b above). 1 (5)
Note: *in one teacher this idea was not probed by the interviewer
TABLE 1b. Partial scienti® c views of the biodiversity explanation components displayed by 12primary teachers
No. ofPartial scienti® c views of explanation components teachers
BD2a Animals become extinct or `get killed off’ (does not specify the reductionin the number of species). 3
BD2b Just knows there is in general a need for diversity of species (no speci® cexample). 2
BD3a Aware of sameness’ but not speci® c about decreasing diversity withinspecies. 5
BD3b Diversity in a species enables it to resist extinction because it is tougheretc (no survival of ® ttest). 6
BD5 Recognises only the living factors (plants/animals) in an ecosystem (noabiotic factors). 4
BD6 Recognises speci® city of living requirements of only some species in anecosystem (not most). 3
BD9 Knows general genetic similarity of individuals in a species or variationsbetween them (not both). 3
BD10 Diversity in general (e.g. defences) allows successful adaptation (notindividual genetic variation). 4
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Understanding Environmental Issues 301
TABLE 1c. Non-scienti® c views of the biodiversity explanation components displayed by 12primary teachers
No. ofNon-scienti® c views of explanation components teachers
BD1 Different species can breed with each other. 4BD3a Wild wheat is bigger, greener, more natural and more tough (rather than
more genetically diverse). 1BD4 `Community’ refers to people rather than plants. 1BD4,5 Confusion between community’ and `ecosystem’. 1BD5. Confusion between ecosystem’ and `biosphere’. 2BD9 Individual variation is due to the environment since they all have the
same genes. 1BD10 Anthropomorphic views about how wild plants resist disease (`more used
to’, have a will’ to). 2BD10 Lamarckist viewÐ it develops resistance to disease which it passes on to
next generation. 1
the number of species in existence, i.e. diversity of species, was decreasing(BD2a) ¼
T2: ¼ a species every three minutes (is) dying out, or somethingincredibly fast like that.
¼ and seven felt that this type of biodiversity was of bene® t to mankind (BD2b).For example:
T12: ¼ rain forests (are) ¼ huge unexplored areas for new drugs andall sorts of potential economic (uses) . .
Seven teachers knew about both the general genetic similarity between indi-viduals in a species and the slight genetic variation that distinguishes them(BD9). This naturally occurring slight genetic variations among individualswithin a species can produce attributes which confer ® tness’ on some individu-als that enables their survival, as described in Darwin’s doctrine of `survival ofthe ® ttest’ . So it is the natural genetic diversity found within a species whichenables it to adapt to new conditions. BD3a refers to the decline in this kind ofbiodiversity, one aspect of which is the increasing dependence of agriculture onfewer varieties of food crops. Only three teachers were able to be speci® c aboutthis decline. For example:
T10: (domestic wheat) is not bred to compete with weeds, it is bred toproduce the best wheat crops, so in doing that it will have lostsome of the characteristics that help it to survive naturally . .
The connection between diversity within a species and the species’ ability toresist extinction through some of its members surviving new pests, diseases orother adverse changes in conditions (BD3b and 10) was recognised by only asingle teacher:
T5: ¼ if a disease was to strike (domesticated wheat) it wouldn’t justharm certain plants, as it probably would for wild wheat, it wouldprobably wipe out the whole ® eld ¼ because it is genetically thesame whereas you’d still get differences in the wild wheat (genetic)makeup.
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All 12 teachers acknowledged the interdependence, or `balance’ , betweenspecies and could give an example of relationships between them in communi-ties, such as feeding or competition (BD4). The often highly speci® c livingrequirements of many species in ecosystems (BD5), which are an expression ofthis interdependence, were less widely recognised (by six teachers). Only six ofthe teachers de® ned the term `ecosystem’ correctly, i.e. included abiotic factors,such as soil or water, as well as living things. The adverse effect of Man onspecies in ecosystems, and consequent loss of biodiversity, was acknowledgedunanimously and all 12 teachers af® rmed that any species was irreplaceableonce it had become extinct.
Partially scienti® c views. Teachers’ partial scienti® c views consisted of generalisedor non-speci® c ideas about the topics investigated. For example, three describedloss of diversity of species more generally as `animals getting killed off’ orbecoming extinct rather than as a reduction in the total number of speciesexisting (BD2a). Two knew that there was a need for diversity of species (BD2b)but were unable to give a speci® c example of how this was of bene® t tomankind, such as, for example, for food or medicines. Similarly, ® ve weremerely aware of the sameness’ of individual plants in a modern wheat ® eld(BD3a) but could not be more speci® c than this about the loss of diversity inspecies. The increased ability of species containing diversity to resist extinction(BD3b) was recognised by six teachers but this was thought to be due to anincreased general toughness rather than to survival of the ® ttest individuals.Similarly, four thought that it was general variability, such as, for example, of`defences’, which enabled a species to adapt rather than to their possession ofmore of the raw material’ for the ® ttest to survive, namely, genetic variation(BD10).
Incomplete ideas were also classi® ed as partial scienti® c views. For example,four described an ecosystem in terms of living things without mentioning abioticfactors (BD5). Three felt that only some species in an ecosystem had speci® cliving requirements (BD6) rather than most ¼
T11: ¼ (there are) species speci® c environments for some (animals) ¼some can adapt (and make new homes elsewhere when the forestis cut down) and some can’t ¼ it depends on what they are andwhether they are temperature-speci® c and all those sorts of things.
¼ and the same number were aware of either the basic genetic similarity ofindividuals or the variation between them (BD9), but not both.
Non-scienti® c views. These may result from erroneous scienti® c knowledge,Life-world (Solomon, 1983) interpretations of phenomena, confusions oflanguage, or anthropomorphic views. For example, four teachers thought differ-ent species can breed with each other (BD1) and one thought that diseaseresistance developed by individuals would be passed on to the next generation(a Lamarckist view contrary to BD10). Another attributed the variation found inindividuals to the environment rather than to genetic variation (BD9):
I: ¼ do all humans have exactly the same genetic makeup?T4: Yes they do ¼ their genes are the same and their environment
changes what they look like.
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Understanding Environmental Issues 303
One teacher gave an everyday view of wild wheat as being `bigger, greener,more natural and tougher (rather than being more genetically diverseÐ BD3a).When explaining the term `ecosystem’ one teacher seemed to confuse it with`community’ and another with `biosphere’ (BD4, 5). Two teachers held anthropo-morphic views about wild plants’ disease resistance, describing them as being`more used to it’ (i.e. the disease) or having `a will’ to resist (BD10).
Carbon Cycle, Ozone and Global Warming
For reasons of space, only the more signi® cant ® ndings in these three areas aredescribed below. A full tabular analysis showing all ECs for each issues isavailable from the authors.
Scienti® c views. Some of the principal ® ndings regarding teachers’ scienti® cunderstanding are shown in Table 2a. For example, with the carbon cycle, ® veof the teachers were aware that carbon dioxide was produced by burning of thecarbon in fossil fuels (CC2). The same number knew about the release of carbondioxide into the atmosphere by both living and decaying things (CC4). Thelocking up’ in fossil fuels of carbon that would otherwise have returned to theatmosphere during decay (CC7) was similarly understood by ® ve teachers. Forexample:
T5: Fossil fuels are very, very old so it makes sense that the carbonwithin them is very, very old . .
I: Why `carbon from the atmosphere of long ago’ (as stated in thestatement being discussed)?
T5: Because that is where the trees and plants (from which coal isformed) get the carbon from, taking it in during photosynthesis.
However, only two teachers seemed to grasp the idea of huge quantities of`ancient carbon’ being released comparatively quickly into today’s atmosphereby the burning of fossil fuels (CC10)Ð in six teachers this idea was absent.
Turning to ozone, 11 of the teachers agreed that ozone is part of the upperatmosphere and has become depleted in amount, i.e. identi® ed the `holes’ in theozone layer (OZ2a). However, only four teachers recognised recent increasedlevels of ground level ozone (OZ3a) and in ® ve teachers this idea was absent. Anidea absent in eight teachers was that ground level ozone is produced by theaction of sunlight on Man-made atmospheric pollutants (OZ7) but there was oneteacher who showed awareness of this:
T8: ¼ the sun will speed up chemical reactions that are going on thatwill produce ozone.
I: You are talking about where? Up there or ¼ ?T8: Down at our level and everywhere I think.
An idea more widely understood, by eight teachers, was the protective effectof the ozone layer against the sun’s harmful rays (OZ2b). Some talked of anincreased occurrence of skin cancer or of UV radiation. Also better understood,by 10 teachers, was the effect of Man-made ozone-destroying chemicals (OZ5)Ða few mentioned CFCs and aerosols.
In the case of global warming, the mechanisms by which a (real) greenhousebecomes warmer than its surroundings (GW1) was grasped by eight teachers.
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TABLE 2a. Teachers’ scienti® c views of explanation components for the carbon cycle, ozone andglobal warming: principal ® ndings (® gures in brackets indicate the number of teachers in which
the particular view was not present at all)
No. ofScienti® c views (i.e. explanation components) teachers
CC2 Because fossil fuels (coal, oil) contain carbon, burning them producescarbon dioxide. 5
CC4 Living things release CO2 into the atmosphere during respiration andthrough bodily decay after death. 5
CC7 Hence, instead of being returned to the atmosphere as carbon dioxidethrough decay, the carbon is locked up’ in the fossil fuel. 5 (3)
CC10 This (i.e. burning fossil fuels) returns a huge quantity of ancient carbon’into the atmosphere over a short period (a few tens of years). 2 (6)*
CC11 Deforestation adds to the problem by reducing a main way in whichcarbon dioxide is removed from the atmosphere, i.e. photosynthesis. 6 (2)
OZ2a The concentration of ozone in the upper atmosphere has becomedepleted everywhere, particularly (as `holes’) over Antarctica. 11
OZ2b In the upper atmosphere ozone is protective, shielding living things fromthe sun’s harmful ultra-violet radiation which, if more reaches Earth,causes increased rates of skin cancer. 8
OZ3a Ground level ozone has greatly increased in recent decades. 4 (5)OZ5 A number of Man-made chemicals (e.g. found in fridges, ® re
extinguishers and some fertilisers) diffuse upwards and destroy upperatmosphere ozone. 10
OZ7 Ground level ozone is produced by the action of sunlight on gasesproduced by human activity, especially burning fossil fuels, e.g. carexhausts and evaporating solvents. 1 (8)
GW1 The inside of a greenhouse is hotter than its surroundings because theglass traps’ energy from the Sun, i.e. allows it in but prevents it beingtransferred away from the greenhouse to the outside. 8
GW2a There has been an observed rise in mean global temperatures(0.5 deg C) this century. 10
GW2b This could give rise to changes in climate patterns which will adverselyaffect human societies. 11 (1)
GW9 This (i.e. Man-made carbon dioxide) leads to an enhanced `greenhouseeffect’ and may be the reason for observed global warming. 1 (5)
Note: *not probed in the case of four teachers
Ten of them acknowledged the fact of global warming (GW2a) and 11 agreedwith the possibility of climate change as a result (GW2b). For example:
T3: ¼ it could be a total disaster for a lot of us ¼ if the Earth is gettingwarmer, we are going to ® nd that things are going to change ¼major problems with farming ¼ crops will no longer grow whereyou are growing them at the moment ¼ more desert ¼ the fearthat the polar (ice) caps are going to melt ¼ sea-levels are going toincrease ¼ a lot of land will go under water . .
However, only a single teacher understood that enhancement of the existingnatural greenhouse effect might be the cause of global warming (GW9).
Partial scienti® c ideas. The research revealed numerous aspects of the teachers’understanding which were incomplete or partially scienti® c (Table 2b). For
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TABLE 2b. Teachers’ partial scienti® c views of explanation components for the carbon cycle, ozoneand global warming: principal ® ndings
No. ofPartial scienti® c views of explanation components teachers
CC1 Just knows that carbon dioxide is an atmospheric gas but not sure howmuch is present. 6
CC3 Aware that carbon dioxide is taken in by plants but cannot account forit afterwards. 6
CC4 Knows only that release of carbon dioxide by living things occurs butunsure of decaying things. 6
OZ1 Ozone is found only in the upper atmosphere/everywhere. 11OZ3b Ozone at ground level is `bad’ or a problem but cannot say why. 3GW7 Knows that Man-made carbon dioxide or `gases’ are warming the
atmosphere but not how they do this. 6GW10 Aware of possible causes (Man or cycles) or uncertainty about which
or need for caution (not all). 6
example, in the case of the carbon cycle, six knew that carbon dioxide was a gaspresent in the atmosphere but were unsure of the approximate proportion(CC1). Although carbon dioxide was known by six teachers to be taken in byplants during photosynthesis, they could not account for what happens to itthereafter (CC3), i.e. that the carbon ultimately can become part of the body ofthe plant (or of an animal eating it). For example:
T6: ¼ carbon dioxide is a product which is needed for photosynthesis.I: What happens to carbon dioxide that, say, children have breathed
out? (T6 ¼ ) Any thoughts about that or does it just stop atphotosynthesis? (T6: I think so).
[(later, talking about storage of carbon in fossil fuels).]T6: Fossil fuels come from plants¼ . I’m not sure I understand about
(the fuels) storing carbon ¼
The same number knew that living things released carbon dioxide into theatmosphere but were unsure about whether decaying things did this (CC4).
With ozone, 11 of the teachers thought it only occurred in any quantity in theupper atmosphere or was `everywhere’ (OZ1), which re¯ ects the lack of aware-ness of recent increased ground level ozone already described. For example:
T9: I think, and again it’s a bit hazy, it (i.e. ozone) is (only found in) oneof the levels of the atmosphere and it’s quite a high up one, I think.
Three who did know about ozone at ground level thought it was `bad’ butcould not go beyond this to say why, i.e. that it is toxic to living things (OZ3b).
In the case of global warming, six teachers knew that the phenomenon iscaused by carbon dioxide or `gases’ but could not go on to explain how they didthis, i.e. by trapping more of the Sun’s energy than would normally be the case(GW7). GW10 describes how there is uncertainty about whether global warmingis part of a natural cycle or a consequence of Man’s activities, but af® rms a needfor action in case the latter should prove to be the case, i.e. the precautionary
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TABLE 2c. Teachers’ non-scienti® c views of explanation components for the carbon cycle, ozoneand global warming: principal ® ndings
No. ofNon-scienti® c views of explanation components teachers
CC1 There is a large proportion of carbon dioxide in the atmosphere. 4CC4 Confusion about the role of carbon dioxide in the process of respiration
in plants, e.g. carbon dioxide is taken in’ .CC6 Fossil fuels are produced by a process of decay. 7OZ2b Holes in the ozone layer cause global warmingÐ numerous explanations& of this, e.g. the holes let more heat from the Sun through to Earth. 9GW3OZ3b Ozone is good for you. 4OZ5 Upper atmosphere ozone has been depleted by the products of burning
fossil fuels. 7GW5 The greenhouse effect is due solely to Man’s activities. 4GW6 All the Sun’s energy incident on the Earth is retained by the planet. 2
principle. Six teachers recognised one or two of these points but not all of them.For example:
T7: (Earth’s temperature) has ¯ uctuated naturally (i.e. recognises naturalcycles) ¼ I don’t think there is no need to worry because what weare doing is speeding (global warming) up a lot (i.e. not aware of theuncertainty about the cause). If we want to preserve life as it is, wehave got to do things to maintain the status quo ¼ (i.e. af® rms theneed for action)
Non-scienti® c views. A number of non-scienti® c ideas in the three areas becameevident from the research (Table 2c). With the carbon cycle, for example, fourteachers thought carbon dioxide occurred in quite large amounts in the atmos-phere (CC1) and the same number were muddled about carbon dioxide andrespiration (CC4), one teacher thinking it was taken in during the process. Seventhought that fossil fuels were produced by decay rather than by the arrest of thisprocess (CC6). For example:
T9: ¼ thinking of fossil fuels such as coal, coal comes about from thedecay of things under the ground.
With ozone, a major misconception, shown in nine teachers, was the attri-bution of global warming to the `holes’ in the ozone layer. Various mechanismsby which this happens, drawn from Life-world ideas and misunderstoodscienti® c knowledge, were put forward by the teachers. For example:
T1: ¼ you’ve got the hole in the ozone layer and ¼ it is letting in UVlight from the Sun which is warming up our atmosphere . .
The idea that ozone is `good for you’ was evident in four teachersÐ perhapsarising from the `urban myth’ portrayed in old seaside postcards or fromconfusion with the bene® cial effects of the ozone layer in protecting us from theSun’s harmful rays. There was also an incorrect view, seen in seven teachers,that the chemicals which destroy the ozone layer include the products ofburning fossil fuels. For example:
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Understanding Environmental Issues 307
T9: ¼ the ozone is disappearing, being worn away (which) isincreasing the temperature ¼
I: What is it speci® cally that is affecting the ozone?T9: ¼ there is a high density of vehicles there all pumping ¼ puffs of
smoke, so it’s the pollution.
In the case of global warming, four teachers thought the greenhouseeffect (GW5) was due solely to Man’s activities and seemed unaware of thenatural greenhouse effect which keeps Earth at a temperature suitable forlife:
I: If Man as a species didn’t exist ¼ would there be a greenhouseeffect?
T10: No.I: So in your view, it’s Man-made?T10: Yes, de® nitely.
Also, two teachers thought all of the Sun’s energy incident upon the Earth isretained by the planet. This shows a lack of understanding of the Earth as abalanced system in which the Sun’s energy taken in equals that escaping intospace (GW6).
Summary
The research has shown that this group of primary teachers had substantialunderstanding of some aspects of the science underpinning the four environ-mental topics investigated. However, other key scienti® c ideas underlyingthese topics were far less well understood by the teachers or were absent. The® ndings showing the teachers’ ideas about biodiversity can be summarised asfollows:
· Scienti® c ideas were displayed by most teachers about the nature of species,their uniqueness and inter-dependence (although there was some uncertaintyabout the nature of ecosystems).
· The loss of diversity of species was largely recognised and Man’s adverseeffect af® rmed by all.
· Many agreed the need for diversity of species and its bene® ts to Man.· While a good number described the nature of diversity within a species in
simple genetic terms, two major ® ndings were teachers’ poor awareness of theloss of this kind of diversity and of the evolutionary mechanism by which itenables adaptation and survival of species.
The ® ndings shown above about the teachers’ ideas in the other three areas, thecarbon cycle, ozone and global warming, can be summarised as follows:
· The locking up’ of carbon within fossil fuels, and the production of carbondioxide from respiration and decay, were recognised by less than half of theteachers.
· A similar proportion knew that burning fossil fuels produced carbon dioxidebut could not interpret this in terms of the return of `ancient carbon’ in acomparatively brief time to our present atmosphere.
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· Uncertainty was shown by a number of teachers about how much carbondioxide is present in the atmosphere, what happens to the carbon in it afterphotosynthesis, and its role in respiration.
· A good number of teachers knew that the ozone layer is protective, that it has`holes’ in it, and that these were caused by Man-made chemicals.
· Far fewer were aware of recent increased ground-level ozone and those thatwere could not specify why this was `bad’ (some thought it was healthy) orhow it was produced.
· Common misconceptions were that the `holes’ cause global warming and thatozone-destroying chemicals come from car exhausts.
· Most were aware of the fact of global warming and the possible climaticconsequences of this.
· Many knew of the mechanism by which a real greenhouse traps’ the sun’senergy, but few were fully aware of how the Earth’s atmosphere mimics thisprocess.
· Full awareness of the uncertainty about the causes of global warming and ofthe precautionary principle was shown by a few teachers but most onlypartially understood this.
· There was little knowledge of Man’s enhancement of the natural greenhouseeffect (or indeed the existence of a natural effect), or awareness of the Earth asa system which both receives and radiates the Sun’s energy.
Using the Findings
The current trend in England and Wales is towards an increased emphasis onthe environment and sustainable development in the school curriculum. Weargued earlier that good subject knowledge is necessary for the best teaching.In the case of the science of environmental issues, our starting point was anexplicit formulation of an appropriate knowledge base, i.e. simple explanationsof environmental issues for primary teachers. Using these explanations asbenchmarks for judging understanding, the study has identi® ed speci® c under-pinning ideas which were well understood and not so well understood in asample of 12 primary teachers. A number of missing concepts and miscon-ceptions are also reported. Although the ® ndings cannot be generalised toall primary teachers, the fairly strong science backgrounds of eight teachersin the sample suggest that some of the dif® culties uncovered may be foundmore widely. It is suggested that both the basic explanations and the dif® cultiesof understanding displayed by the teachers can usefully inform programmesof professional development. In ful® lment of the second goal of the researchstated at the start of this article, a guide to help teachers develop their know-ledge in all seven areas identi® ed earlier is about to be published (Summers etal., 2000).
The guide makes use of both the interview ® ndings and a subsequentquestionnaire study (Summers et al., submitted). For each environmental issue,it includes:
· A `basic story’. This is a prose version of the explanation components whichacts as a simple account of the issue appropriate (in our judgement) for manyprimary teachers. The inspiration for this approach was the use of explanatory
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Understanding Environmental Issues 309
stories in the Nuf® eld Foundation report Beyond 2000 (Millar & Osborne,1998).
· A summary of the basic story (essentially the explanatory components shownin the Appendix of this article).
· A very brief summary of the research highlighting those aspects of the issuewhich were well understood, not so well understood, non-scienti® c or absent.
· Sections which deal speci® cally with non-scienti® c or absent ideas, comparingthe views uncovered by the research with scienti® c interpretations.
· A `beyond the basics’ section which further develops the science underpinningeach issue for those with stronger scienti® c backgrounds or who simply wishto know more.
· Diagnostic questionnaires (with answers) which focus on the explana-tion components for each issue and enable teachers to assess their ownstarting points. These were developed as a parallel strand of the presentresearch.
The guide outlined above has a limited focus on scienti® c understanding. Weemphasised earlier that this is only one element of the complex amalgam ofknowledge, values, skills and associated pedagogical knowledge which under-pins education about the environment and sustainable development. How caninsights into this complexity be gained in such a way that there are realadvances in teaching and learning in these areas?
Rather than speculate on these issues, our own view is that they are besttackled through research which is grounded in the realities of classroom lifeand curriculum mandates. To these ends, a project is now underway tobuild case studies of the teaching and learning of sustainable development inprimary classrooms (Summers et al., 1999). This is a collaborative undertakingbetween university science and geography education tutors in partnershipwith eight primary school teachers. An important goal of this work is to identifyspeci® c examples of sustainable development topics that are accessible toprimary children and which can be the vehicle for developing the underpinningconcepts and exploring options for human action. Moreover, planning andimplementation will take place within the framework of the new NationalCurriculum, taking account of the scienti® c and geographical requirements,as well as new national guidelines for citizenship education (which in thepublished curriculum make explicit links to the environment and sustainabledevelopment).
But perhaps the most important purpose of the work is to move beyond alimited focus on teacher subject knowledge relevant to environmental issues andsustainable development (although enhancement of this will be a key ingredi-ent), and identify pedagogy which is effective in developing children’s factualknowledge, understanding and values in these domains.
Acknowledgements
The authors would like to thank the 12 teachers who took part in this research,and Esso UK plc and ICI Technology for providing the funds needed to carryout the work.
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Notes on Contributors
MIKE SUMMERS is a University Research Lecturer in Oxford UniversityDepartment of Educational Studies where he directs the Primary SchoolTeachers and Science (PSTS) project.
COLIN KRUGER has been a primary school Head Teacher and is now thePrimary School Teachers and Science (PSTS) Project Research Of® cer.
ANN CHILDS is a University Lecturer in Chemistry Education and is a memberof PSTS.
JENNY MANT is a Senior Lecturer in Primary Science at Oxford BrookesUniversity and is also a member of PSTS.
The PSTS project has for many years produced research-based teacher educationmaterials to help primary teachers develop their understanding of scienceconcepts. More recently it has extended its sphere of activities to includeenvironmental education, and is currently conducting a major funded projectconcerned with the teaching of sustainable development in primary schools.
REFERENCES
BOYES, E., CHAMBERS, W. & STANISSTREET , M. (1995) Trainee primary teachers’ ideas about theozone layer, Environmental Education Research, 1(2), pp. 133± 145.
COUNCIL FOR ENVIRONMENTAL EDUCATION (1998) Education for Sustainable Development in theSchools Sector: a report to DfEE/QCA from the Panel for Education for Sustainable Development(Reading, Council for Environmental Education).
DFEE (1998) Teaching: high status, high standards. Requirements for courses of initial teacher training(London, Department for Education and Employment).
DOVE, J. (1996) Student teacher understanding of the greenhouse effect, ozone layer depletionand acid rain, Environmental Education Research, 2(1), pp. 89± 100.
MILLAR, R. & OSBORNE, J. (Eds) (1998) Beyond 2000: science education for the future. The report of aseminar series funded by the Nuf® eld Foundation (London, Kings College London).
QUALIFICATIONS AND ASSESSMENT AUTHORITY (1999) The review of the National Curriculum inEngland: the consultation materials (London, Quali® cations and Assessment Authority).
SOLOMON, J. (1983) Learning about energy: how pupils think in two domains, European Journalof Science Education, 5(2), pp. 49± 59.
SUMMERS, M. (1994) Science in the primary school: the problem of teachers’ curriculumexpertise, The Curriculum Journal, 5, pp. 179± 193.
SUMMERS, M. & MANT, J. (1995) A misconceived view of subject matter knowledge in primaryscience education, Research Papers in Education, 10(3), pp. 303± 307.
SUMMERS, M. & KRUGER, C. (1994) A longitudinal study of a constructivist approach to improv-ing primary school teachers’ subject knowledge in science, Teaching and Teacher Education,10(5), pp. 499± 519.
SUMMERS, M., KRUGER, C., MANT, J. (1998) Teaching electricity effectively in the primary school:a case study, International Journal of Science Education, 20(2), pp. 153± 172.
SUMMERS, M., CHILDS, A. & CORNEY, G. (1999) Teacher education for sustainable development:case studies of effective primary practice. Unpublished research proposal accepted forfunding by the Esme e Fairbairn Charitable Trust.
SUMMERS, M., KRUGER, C., MANT, J. & CHILDS, A. (2000) Understanding the Science of EnvironmentalIssues: a research-based guide for primary and non-specialist secondary teacher education (Hat® eld,Association for Science Education).
SUMMERS, M., KRUGER, C., MANT, J. & CHILDS, A. (in press) Understanding the science ofenvironmental issues: development of a subject matter guide for primary teacher education,International Journal of Science Education.
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Appendix
Explanation Components for Biodiversity, the Carbon Cycle, Ozone and Global Warming
BIODIVERSITY (BD)Preliminary knowledge1. A species is a group of living things which can
breed with each other and produce fertileoffspring.
Recognising the two issues (an issue 5 what ishappening and why it is of concern)2a. There is a loss of the diversity of species2b. This diversity is needed for aesthetic, moral
and practical (e.g. bene® cial to Main reasons.
3a. There is a loss of the diversity within species.3b. This diversity is needed to resist extinction by
pests or disease.
Diversity of species: main ideas4. Living things exist in communities made up of
many inter-dependent species linked by anetwork of relationships, e.g. feeding,competition.
THE CARBON CYCLE (CC)Preliminary knowledge1. Carbon dioxide (CO2) is a gas found in very
small amounts in the atmosphere.
2. Because fossil fuels (coal, oil and natural gas)contain carbon, burning them produces carbondioxide.
The natural carbon cycle3. During photosynthesis, plants remove CO2
from the atmosphere with the carbon eventuallybecoming much of the tissue of plants,herbivorous animals or their predators.
4. Living things release CO2 into the atmosphereduring respiration and through bodily decayafter death.
5. For millions of years these processes ofremoval and release kept the amount of CO2 inthe atmosphere about the same (i.e. the twoprocesses balanced each other).
5. The living things interact with each other andwith their non-living environment to form abalanced, self-suf® cient unit called anecosystem, e.g. a particular woodland, forest,tundra, stream, pond etc.
6. Most species in the wild can survive only inthe conditions pertaining in their particularecosystem.
7. Human activity (e.g. habitat destruction, over-harvesting, pollution, foreign introductions)adversely affects many ecosystems, causingextinction of species and consequent loss ofbiodiversity.
8. These lost species cannot be replaced.
Diversity within species: main ideas9. All members of a species have the same basic
genetic makeup but there is a diversity due tosmall variations between individuals.
10. These variations enable some individuals tosurvive and the species to adapt to changedconditions (e.g. to resist extinction by newpests or diseases which kill the restÐ see 3babove).
OZONE (OZ)Preliminary knowledge1. Ozone is a gas found concentrated in the upper
atmosphere and at ground level.
Recognising the two issues (an issue 5 what ishappening and why it is of concern)2a. The concentration of ozone in the upper
atmosphere has become depleted everywhere,particularly (as `holes’) over Antarctica.
2b. In the upper atmosphere ozone is protective,shielding living things from the Sun’s harmfulultra-violet radiation which, if more reachesEarth, causes increased rates of skin cancer.
3a. Ground level ozone has greatly increased inconcentration in recent decades.
3b. Ozone is toxic to living thingsÐ it damagesplants and causes respiratory problems inhumans and animals.
Ozone layer: main ideas4. The amount of upper atmosphere ozone
normally remains about the same.
A side effect of the natural carbon cycle Ð formationof fossil fuels6. When decay of living things’ bodies is
prevented (e.g. through burial in environmentslacking oxygen), fossil fuels are formed.
7. Hence, instead of being returned to theatmosphere as CO2 through decay, the carbonis locked up’ in the fossil fuel.
8. Fossil fuels were formed in the distant pastover a period of millions of years, locking up ahuge quantity of CO2.
Disturbance of the natural carbon cycle9. Man has disturbed the balance of the natural
cycle since the Industrial Revolution, and moreso in recent years, by the rapid increase in theburning of fossil fuels.
10. This returns a huge quantity of `ancient carbon’as CO2 into the atmosphere over a short period(a few tens of years).
11. Deforestation through burning adds to theproblem since the carbon making up the woodof the trees is released into the atmosphere asCO2.
GLOBAL WARMING (GW)Preliminary knowledge1. The inside of a greenhouse is hotter than its
surroundings because the glass traps’ energyfrom the Sun, i.e. allows it in but prevents itbeing transferred away from the greenhouse tothe outside.
Recognising the issue (an issue 5 what is happeningand why it is of concern)2a. There has been an observed rise in mean global
temperatures (0.5 deg C) this century.2b. This could give rise to changes in climate
patterns which will adversely affect humansocieties.
Global warming: main ideas3. Some gases in the Earth’s atmosphere act like
the glass in a greenhouse by trapping some ofthe energy from the Sun.
4. Carbon dioxide is the most importantgreenhouse gas over which Man has control.
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5. A number of man-made chemicals (e.g. foundin fridges, ® re extinguishers and somefertilisers) diffuse upwards and destroy upperatmosphere ozone.
6. `Repair’ of the ozone layer occurs naturally butmore slowly than the rate of destruction.
Ground level ozoneÐ main idea7. Ground level ozone is produced by the action
of sunlight on gases produced by humanactivity, especially burning fossil fuels, e.g. carexhausts and evaporating solvents.
5. The trapped energy warms the Earth andatmosphereÐ this is the natural greenhouseeffectÐ enough to give an average temperaturesuitable to sustain life.
6. Overall, the incoming energy from the Sunequals the energy escaping (not trapped by thegreenhouse effect); this balance (energy in 5energy out) keeps the Earth at the sametemperature, on average.
7. Man is increasing the concentration ofgreenhouse gases in the atmosphere,particularly carbon dioxide, which results inmore energy being trapped and the balanceupset.
8. The Man-made increase in atmospheric carbondioxide is due to burning of fossil fuels anddeforestation through burning.
9. This leads to an enhanced `greenhouse effect’and may be the reason for observed globalwarming.
10. It is uncertain whether observed globalwarming is due to natural cycles or to Man-made contributions, but the consequences ofthe latter are so profound that precautionarymeasures should be taken.
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