Red Lines & Hockey Sticks A discourse analysis of the IPCC’s visual culture and climate science (mis)communication
Thomas Henderson Dawson
Department of ALM Theses within Digital Humanities Master’s thesis (two years), 30 credits, 2021, no. 5 Author Thomas Henderson Dawson
Title Red Lines & Hockey Sticks: A discourse analysis of the IPCC’s visual culture and climate science (mis)communication.
Supervisor Matts Lindström
Abstract Within the climate science research community there exists an overwhelming consensus on the question of climate change. The scientific literature supports the broad conclusion that the Earth’s climate is changing, that this change is driven by human factors (anthropogenic), and that the environmental consequences could be severe. While a strong consensus exists in the climate science community, this is not reflected in the wider public or among poli- cymakers, where sceptical attitudes towards anthropogenic climate change is much more prevalent. This discrep- ancy in the perception of the urgency of the problem of climate change is an alarming trend and likely a result of a failure of science communication, which is the topic of this thesis. This paper analyses the visual culture of climate change, with specific focus on the data visualisations com- prised within the IPCC assessment reports. The visual aspects of the reports were chosen because of the prioriti- sation images often receive within scientific communication and for their quality as immutable mobiles that can transition between different media more easily than text. The IPCC is the central institutional authority in the climate science visual discourse, and its assessment reports, therefore, are the site of this discourse analysis. The analysis tracks the development and variations in the IPCC’s visual culture, investigates in detail the use of colour and the visual form of the “Hockey Stick” graph. This work is undertaken to better understand the state of the art of climate science data visualisation, in an effort to suggest the best way forward to bridge the knowledge gap between the scientific community and the public on this important issue. The thesis concludes that a greater em- phasis on the information aesthetics of their data visualisations could benefit the IPCC’s pedagogical reach, but that it may also be argued that it is not the IPCC’s role in climate change discourse to produce the most visually persuasive images. That they exist as a tone-setting institution that provides authority to entities that are better geared towards wider communication, such as journalism and activism.
Key words Climate Change, IPCC, Data Visualisation, Information Aesthetics, Science Communication.
2 Table of Contents
Introduction…………………………………………………………7 Purpose Statement and Research Questions…………………………...……..10 Previous Research…………………………………………………………….11 Theory & Method…………………………………………………………….15 Method………………………………………………………………………..16 Theory………………………………………………………………………...18 Materials………………………………………………………………………23 Relevance and Topicality……………………………………………………..24 Development and Variation in IPCC Data Visualisation………..25 First Assessment Report (1990)………………………………………………26 Supplementary Report (1992)………………………………………………...29 Second Assessment Report (1994)……………………………………………29 Third Assessment Report (2001)……………………………………………...32 Fourth Assessment Report (2007)…………………………………………….34 Fifth Assessment Report (2014)………………………………………………36 A note on two-dimensional globe projections………………………………...37 Recurring Colours: Prominence of the Colour Red……………..38 History and cultural associations……………………………………………...39 Infographics…………………………………………………………………...40 In (the English) language……………………………………………………..41 Colour in IPCC reports………………………………………………………..42 Colour in non-IPCC climate visualisations…………………………………...47 Recurring Forms: The “Hockey Stick” Graph & Upward Exponentials………………………………………………………...49 Discussion and Conclusions………………………………………..59 Conclusions…………………………………………………………………...66 Bibliography………………………………………………………..67 Literature……………………………………………………………………...67 Appendix……………………………………………………………………...70
3 Table of Figures
Figure 1. IPCC, 1990, Climate Change: The IPCC Scientific Assessment, Cam- bridge University Press, Cambridge, p.xxii. ……………………………….27 Figure 2. IPCC, 1990, Climate Change: The IPCC Scientific Assessment, Cam- bridge University Press, Cambridge, p.xiv. ……………………………….28 Figure 3. IPCC, 1990, Climate Change: The IPCC Scientific Assessment, Cam- bridge University Press, Cambridge, Front Cover. ………………………..29 Figure 4. IPCC, 1992, Climate Change 1992: The Supplementary Report to The IPCC Scientific Assessment, Cambridge University Press, Cambridge, Front Cover. ……………………………………………………………………...29 Figure 5. IPCC, 1994, Climate Change 1994: Radiative Forcing of Climate Change and An Evaluation of the IPCC IS92 Emission Scenarios, Cambridge Univer- sity Press, Cambridge, Front Cover. ………………………………………30 Figure 6. IPCC, 1994, Climate Change 1994: Radiative Forcing of Climate Change and An Evaluation of the IPCC IS92 Emission Scenarios, Cambridge Univer- sity Press, Cambridge, p.10. ………………………………………………30 Figure 7. IPCC, 1994, Climate Change 1994: Radiative Forcing of Climate Change and An Evaluation of the IPCC IS92 Emission Scenarios, Cambridge Univer- sity Press, Cambridge, p.37. ………………………………………………31 Figure 8. IPCC, 2001, Climate Change 2001: Synthesis Report, Cambridge Univer- sity Press, Cambridge, Front Cover. ……………………………………....32 Figure 9. IPCC, 2014, Climate Change 2014: Synthesis Report, IPCC, Geneva, Front Cover. ……………………………………………………………….32 Figure 10. IPCC, 2001, Climate Change 2001: Synthesis Report, Cambridge Uni- versity Press, Cambridge, p.34. ……………………………………………33 Figure 11. IPCC, 2007, Climate Change 2007: Synthesis Report, Cambridge Uni- versity Press, Cambridge, Front Cover. ……………………………………34 Figure 12. IPCC, 2007, Climate Change 2007: Synthesis Report, Cambridge Uni- versity Press, Cambridge, p.6. ……………………………………………..35 Figure 13. IPCC, 2007, Climate Change 2007: Synthesis Report, Cambridge Uni- versity Press, Cambridge, p.9. ……………………………………………..36 Figure 14. Harris, J. 2016, Why all world maps are wrong, Vox/Youtube, viewed 30 May 2021, < https://www.youtube.com/watch?v=kIID5FDi2JQ&ab_ channel=VoxVoxVerified>. …………………………………………….…37 Figure 15. Greenbaum, H. and Rubenstein, D. 2011, The Stop Sign Wasn’t Always Red, The New York Times Magazine,
4 Figure 16. Health and Safety Executive, 2021, No access for unauthorised persons, HSE, viewed 30 May 2021,
5
6 Introduction
The scientific community of climate researchers have in the last thirty years formed a strong international consensus that the Earth’s climate is changing, that average global temperatures are rising, and that this fact will likely result in an environmen- tal and ecological crisis. Climate scientists as a group are approaching a unanimous consensus on the conclusion that the observed warming of the planet is caused by human factors, with one recent survey finding 100% agreement on the issue (Powell 2019, p.183) and findings of similar surveys generally hovering between 95-100% agreement (Anderegg 2010; Cook 2013; Cook 2015). What few voices of dissent that do exist within the scientific community have generally been derided for pro- ducing work which does not replicate, contains a pattern of common mistakes, or methodological flaws (Benestad et al. 2016, p.699). This consensus has been formed in large part by the compilation of the most pertinent current research into assessment reports by the Intergovernmental Panel on Climate Change (IPCC). Five such reports have been compiled since 1990, with the most recent report having been published in 2014, and a sixth report is due to be published in 2022. Climate change poses an existential threat to the global population, posing a particular threat to those developing nations that can ill afford to defend against the increased threat of drought, wildfires, flooding, and other natural disasters (Men- delsohn 2008, p.5). A changing climate – changing at a faster rate than might be expected to occur naturally due to human activity – has the potential to cause seri- ous and irreversible ecological damage; which both threatens the existence of large numbers of species of plants and animals, and as a result – again – the survival of humans. Left unaddressed, climate change has the possibility to initiate a mass ex- tinction event that has not been seen on Earth for millions of years. The situation is, therefore, a crisis, which only decisive action on an international scale will serve to avoid. The problem in the efforts to mitigate against this crisis is that while there is a remarkably strong scientific consensus on the human factors driving climate change, the threats posed, and the solutions required; the general public and the policymakers elected to represent them are often sceptical at a much higher rate than the scientific community. Scepticism about the nature and urgency of the prob- lem, and what – if any – action is required to combat it hovers around 30% across the global population, with some countries as low as 10% but some as high as over 50% (Pew Research Centre 2018). This disparity between the scientific consensus and public opinion signifies a breakdown in communication between scientific research bodies and organisations, and wider society. There are likely numerous socio-political causes that influence
7 this disparity which will not form part of the focus of the present study. A full ex- amination of the factors which might cause such a disparity would contain more fields of study and be wider in scope than the size of this project allows. But for the purposes of contextualising the problem that is addressed in this study, I will list three of the biggest obstacles to climate science communication to the general pub- lic, as I see them. One factor in a perceived breakdown in scientific communication in the de- veloped world is a recent rise in populism, epitomised by the prominent British politician Michael Gove when he stated: ‘I think the people in this country have had enough of experts, with people from organisations with acronyms saying that they know what is best and getting it consistently wrong’ (Sky News, 3 June 2016). This rise in populist politics has resulted in an increased scepticism in scientific author- ity, particularly that of international organisations. Another factor is a general lack of scientific education among the general population, which makes information lit- eracy on an admittedly complex topic such as climate change a challenge. Finally, the influence of counter-information PR strategies and political lobbying from par- ties with vested interests in downplaying the effects of climate change – or at least hose beyond the actions of individual consumers – such as fossil fuel companies. Which has served to muddy the water of the public discourse around climate change and the crisis it is causing. While acknowledging their existence, the present study will generally set aside the socio-political factors alluded to above in order to address one particular aspect of the scientific communication on anthropogenic climate change. Choosing instead to view the visualisation of climate science data/information as a discourse all of its own, and investigate it using a humanistic approach of a discourse analysis of this specific visual culture. To adopt the phraseology of discourse analysis, the assessment reports of the IPCC are the institutional literatures that have the greatest power to produce a dis- cursive formation which can shape its subject – anthropogenic climate change – into a discourse which is productive and persuasive, not just for the purposes of communicating within the community of climate scientists but also outside of it. It is perhaps also worth highlighting that the IPCC is a sort of forum for cli- mate science researchers, with the reports representing a summary of the consensus reached within that forum. During the early period of the IPCC’s existence, its pur- pose was very much to attempt to establish a link between human activities and observed changes in the Earth’s climate, with an emphasis on the mutual persuasion between scientists. However, more recent assessment reports have been produced in conditions where the consensus among the scientists who contribute to the re- port’s contents has been remarkably strong. As a result, the emphasis has turned away from persuasion within the bounds of the scientific community and instead
8 been turned outwards towards the general public, but with particular emphasis on policymakers. The IPCC as an organisation has shifted to producing a discourse which is productive outside of climate science circles and not just within them. This has co- incided with a wider cultural shift towards the visual as a primary medium for com- munication, which transcends linguistic barriers and has an enhanced capacity to communicated complex ideas in a more accessible and efficient manner than lan- guage. Therefore, the present study will attempt to better understand the breakdown in communication between climate science discourse actors – principally the IPCC – and the wider public. It will do so by approaching the visualisation of climate change data as a sub-discourse of the wider discourse of climate science. By apply- ing a discourse analysis methodological approach to this specific visual culture, this study will attempt to describe and critique the information aesthetics of the IPCC and other climate data visualisation objects it scrutinises, in order to better under- stand their discursive power and ask the question: how do they communicate the information they contain and how has this changed through the various iterations of the assessment reports? This thesis is focusing on this aspect of climate visual culture in particular, rather than the culture as a whole because these visual objects represent the most transferable information objects within this discourse. This specific focus is im- portant because the scientific climate discourse does not generally deal in the emo- tionally charged iconographic imagery of activism and journalism (with the notable exception of IPCC report covers). And those activist discourses do not engage with the language of written scientific reports in a comprehensive way. But data visual- isation artefacts represent a form of immutable mobile that can move through these related discourses with limited friction and carry an argument from the scientific discourse through to journalism and activism with limited loss of understanding. The ease of movement with relatively low loss of information is complicated, how- ever, by the degree to which these visualisations often need to be reformed or re- worked from a design perspective to better capture the attention of – and persuade – the audience. This gap between what scientific data visualisation often feels is the more authoritative and neutral mode and the more emotive and argumentative modes of journalism and activism. This is an important point for the consideration of climate science data visualisation as immutable mobiles and when considering the failures of communication on this issue. This is an analysis of a discourse followed by consideration of the practical implications of that discourse as it relates to the problem of scientific communica- tion, and climate change communication in particular. The analysis will track the development and variations of data visualisations contained within the IPCC as- sessment reports, before moving on to focus on two specific visual aspects of the data visualisation in the reports and in the wider climate science discourse: the use
9 of the colour red and the controversy around Michael Mann’s so-called “Hockey Stick” graph.
Purpose Statement and Research Questions While a great deal of research has been conducted in the field of science communi- cation in the field of information studies, and some research has even been at- tempted to understand the effectiveness of data visualisation in the scientific litera- ture of climate science from the perspective of the natural sciences and even social sciences (Neset et al. 2009; Daron et al. 2015; Harold et al. 2019), there has been virtually no attention paid to this question from the humanities and this is what this thesis sets out to correct. The purpose of this visual discourse analysis study is to describe the information aesthetics of data visualisations within IPCC assessment reports and to compare and contrast these with examples from the wider discourse around climate science visual culture.
The study is based on the following research questions:
How does the visualisation of climate science research exhibited in IPCC assess- ment reports represent a productive sub-discourse within the wider discourse of cli- mate science that serves to effectively persuade outsiders by making effective use of an information aesthetics framework?
How might the information aesthetics of the data visualisation exhibited in IPCC assessment reports be characterised?
How has the compositionality of the IPCC’s data visualisation changed or re- mained the same through successive assessment reports?
How does the data visualisation in the IPCC’s assessment reports compare to climate change data visualisation examples exhibited in other media?
10 Previous Research While much of the scholarly concern for describing and understanding data visual- isations in climate science has originated from within the natural sciences, there has been a small amount conducted from the perspective of humanists and social scien- tists. While this project is in some sense an exercise in information aesthetics re- search, it is interesting to note that this is a relatively unique approach to the topic and certainly to this particular set of empirical materials, with previous research into climate science information aesthetics being vanishingly small. What research that has been conducted into climate change visual culture has two main characteristics. The first is that approaching the objects from this perspec- tive – a perspective slightly removed from the invested position of the natural sci- ences – has resulted in the uncovering of a fresh perspective on the problem of ineffective climate science communication. It is in this sense that this current paper aims to continue in the tradition of previous research. The second is that studies have often tended to focus on the visual culture of climate change as a whole, pri- oritising the – admittedly more visually stimulating – iconographic photography or art associated with climate change journalism and activism, while paying little at- tention to the visuality of climate science data visualisation from organisations such as the IPCC, which are set up ostensibly to be non-partisan. There have been a small number of humanistic and social science-oriented investigations into climate change visual culture, and these have approached the topic from various different angles. Adam Brenthel (2016) has produced one of the most comprehensive surveys of this specific visual culture. Brenthel approached the topic from the perspective of an Art Historian and attempted to unpack the vis- ual culture in its entirety; including ‘scientific articles, news reports, websites, pam- phlets, videos, and other kinds of public outreach material produced by research institutes’ (Brenthel 2016, p.19). Brenthel surveys a broader scientific communica- tion landscape than is the purpose of this thesis and interrogates it using the tools made available by compositional and iconographic approaches to visual culture analysis. This is a useful method for investigating photographic or visual art empir- ical materials, but the specific sub-genre of data visualisation does not provide the same interpretive material for “exploring beneath the surface” or “finding hidden meaning” that Art History approaches often aim to exploit. Instead, a discourse analysis is more appropriate for this kind of investigation, which the section on theory and method will explore. Brenthel also aims to better understand a perceived problem of failed science communication but approaches the problem with a larger scope, paying little attention to these specific and important reports which form the core of this thesis. Much of the other investigations that have approached similar materials to this thesis, or similar topics to this thesis from a humanistic or social science per- spective, have done so in a way that is more tangential than Brenthel’s work – which
11 is the most direct companion to this paper. Another important work in this area of research was conducted by Julie Doyle (2007), who used a more similar methodo- logical approach to a different set of materials. Doyle conducted a visual discourse analysis of campaigns organised by the environmental charity Greenpeace during the 1990s and 2000s, with special emphasis on their campaigns that focused on climate change. This research focused on the visual rhetorics as well as the textual discourse of the campaigns and sought to historicise them by tracking the develop- ment over time. The scope of this project was naturally less focused on visualisa- tions because it also considered the textual component of the campaigns. In addi- tion, the focus on a campaigning charity group rather than an intergovernmental organisation means the research addresses the issue of climate change communica- tion from a different perspective. Where the charity’s role is to spread awareness, and the materials they produce have a certain license to be partisan, the IPCC has a more defined target audience of other members of the scientific community and policy makers whom it attempts to persuade and convince to take action. The IPCC occupies a different space within climate science discourse, it possesses a degree of gravitas and scientific prestige compared to an organisation like Greenpeace, but it is also beholden to a certain rigour and accuracy that an organisation with license to be partisan does not. Taking an altogether different approach, Sean Cubitt (2012) compared the visual culture of climate science and instances of narrative fiction filmmaking. In his reading of the perceived communication failure on climate change he identified two major obstacles. He argued that compared to fictional films climate change visualisations are not given the same flexibility with regards to meaning making and believability. Outlandish incidents can occur in the course of a narrative film, but the audience is willing to accept it as believable and part of the reality because of a willingness to suspend disbelief. Phenomena that are not a part of everyday life are acceptable to audiences in film, but in climate science data visualisation, that which is not tangible or relatable to everyday life is often more likely to be rejected by audiences as unbelievable. He argues that the bar for persuasion is much higher for climate science communication. This resonates with an observation by Brenthel that technological solutions are often cited as the most likely means of bridging the communication gap in cli- mate science. Brenthel argues that this idea that we need better technology to cap- ture the impact of climate change as well as more advanced means to represent data from climate research is a fallacy. The need, he says, is for better story telling; story telling that can emote and provoke a reaction even if that reaction is rooted in met- aphor or symbolism and not necessarily in hard data. This he claims is more effec- tive than attempting to render images more “real”. Cubitt makes a further observation that is particularly prescient for climate data visualisation. He states that because of the visual medium ‘[a]ll data
12 visualizations tend toward spatial solutions for the problems raised by time’ (Cubitt 2012, p.293). This poses a particularly tricky challenge to individuals and organi- sations who try to visualise the problem of climate change and must attempt to re- port on a phenomenon where time is important: the large scale of time the Earth’s climate is described over, and the time society has left to address the issue. In the face of a time sensitive problem, data visualisation specialists only have space to communicate with. This issue may shed some light on the IPCC’s overreliance on line graphs as a data visual form. Moving more into a social science space, some work has been done on climate science communication in media studies. Notably by Brigitte Nerlich and Rusi Jas- pal (2013) who have done a great deal of work on the portrayal of climate and weather in the media. Some of Nerlich and Jaspal’s work has focused on the media, extreme weather events, and the emotional reactions of audiences. They tended to find that it is possible to overemote on these topics in the media, that overly emotive coverage of extreme weather and climate change tends to make viewers become defensive and disengage with the topic. They find that this can be a fatal flaw in maintaining the attention of a viewing audience; but that, despite this, media outlets make the same mistake over and over again. They observed that even a relatively mild announcement from the IPCC, for example, was supplemented with imagery of extreme weather; which they insist is not effective and has a tendency to under- mine scientific communications strategies. In this sense, Nerlich and Jaspel are in disagreement with Brenthel, who – as outlined earlier – suggests emotive and reac- tion provoking images are a better means of communicating the urgency of the problem of climate change. But this is not supported by the findings of Nerlich and Jaspel. Regarding the psychological perspective on climate science communication and the effect it has on an audience, George Lakoff (2010) does not comment spe- cifically on the merits of emotive imagery. However, Lakoff’s work on cognitive- linguistic issues of climate change offer interesting insights and echo conclusions drawn by Cubitt. What Lakoff suggests is that, on a cognitive level, humans lack the adequate tools to frame a problem like climate change. At least with respect to producing images that are meaningful and socially impactful, he argues that humans are not well equipped to comprehend a problem that occupies the temporal and special scope of climate change. In addition to assigning current visualisation tools as too abstract and inadequate for the purpose, Lakoff argues that this inadequacy is rooted in a human psychological blocker on comprehending the possibility of change in the future. These findings by Lakoff are reinforced by the work of Mark Nuttall (2012), who approaches climate change visualisations from an anthropological perspective. He argues that humans are capable of understanding the present and to an extent the past, but that visualising the future often results in some kind of reference to the
13 present or the past, that humans struggle to imagine things beyond what they al- ready know. This finding is in specific reference to scientific climate research vis- ualisations and leaves open the possibility of more artistic expressions of climate change, as is promoted by Brenthel and Cubitt as more effective climate visual me- dia. One final prominent piece of work on climate change visualisations from a humanistic or social science approach is the research carried out by Saffron O’Neill and Mike Hulme on the iconography of climate change. They argue for the essential meaning making of icons in climate science as a visual culture. They argue that rather than, say, the scientifically conventional images that appear in IPCC reports, Greta Thunberg and Al Gore’s film An Inconvenient Truth are better vehicles for scientific communication because of their iconoclastic nature. This thesis would argue that particularly Michael Mann’s “Hockey Stick” graph is iconic in its own way. Crucially they point out that relatable icons are more powerful than those which are culturally, socially or geographically distant. But taking their point, the scientific research underpinning the more iconic images still have value and act as originators in the discourse. O’Neill and Hulme view icons as useful proxies for what is a difficult “en- emy” to represent visually. The invisible threat of climate change is only rendered visible when it manifests. This challenge is interesting to observe in the assessment report covers produced by the IPCC and how these have developed and changed over time. O’Neill and Hulme also make an interesting distinction between icons and representations of icons, which is fruitful to consider when discussing the “Hockey Stick” graph and its legacy. In their work on climate change visualisations, Birgit Schneider and Lynda Walsh (2018) identify a peculiar problem with more advanced climate research data visualisations. They discuss the implications of tools which allow the viewer to “zoom” in on different geographical areas in order to see how that area might be affected in the future by a warming climate. Taking a media studies and politics approach to the question, they identified the purpose of this tool to help localise the problem of climate change and to help people to understand that the problem is not distant but close to home. This resonates with the discussion of O’Neill and Hulme about familiar icons. However, Schneider and Walsh see a problem in this possibil- ity of “localising” climate change consequences. They argue that showing the prob- lem as local rather than global could have the opposite of the desired effect of en- gaging more people, instead it might serve to disengage those people whose local area is less likely to be affected. They argue that presenting the problem as global, as a concern for everybody, is a better approach. Joseph Daron et al. (2015) identified a gap in knowledge on the topic of ef- fective climate science visualisation. They argue that we do not know enough about what makes for “good” climate visualisations. They carried out a survey to gauge
14 comprehension and found that choices of graphical form and style had a major im- pact on how well an audience understood the objects presented to them. An example of previous research of extreme importance for this particular thesis is the work carried out by Jordan Harold et. al (2019) on the IPCC and its visual communication. This paper took a social science and computer science ap- proach to the problem, interviewing IPCC report authors on their opinions on the process of producing the IPCC’s visualisations, as well as some graduate students, and supplemented these findings with computational methods of discerning the “readability” of the visualisations. The IPCC report authors reported that they felt the visualisations were not ideally suited to be understood by their target audience (policymakers) but that aesthetic conventions on data visualisation in a natural sci- ences research setting constrained the range of options available to the authors. These interview findings were reinforced by the second part of the study that used computational methods to quantify the readability of the visualisations and gauge the level of comprehension required to understand them. They found that the visu- alisations contained large amounts of information, used multiple colours, and were packed densely with visual elements; they concluded that these characteristics made for a collection of images that were difficult to comprehend without expert inter- pretation. These findings are illuminating in the problem of climate science mis- communication, but while they cover a social science and a quantitative computa- tional methods approach, the purpose of this thesis is instead to approach this same problem from a humanistic perspective.
Theory and Method The following section will describe the theoretical and methodological approach of this thesis. It will detail the interpretive resources utilised to analyse the data and to define important concepts for that interpretive framework. It will describe the choice of methodological approach as well as the choice of empirical data, and the motivations behind these choices. In justifying this investigation’s choice of theoretical and methodological ap- proach, there is first the need to attempt to answer some fundamental questions. The object of enquiry for this thesis is a collection of objects which are visual in nature, and so there are some fundamental questions around how to regard visual objects as empirical data in an academic thesis. We might begin by asking: how do we think about images in an academic context? Can we treat them like text, or are they some- how different? How do they work? (Can we conduct a close reading of them? Can they [alone] form a discourse?).
15 Method The general methodological approach of this thesis takes the form of a dis- course analysis. Discourse analysis is that scholarly investigation which is con- cerned with the discursive production of some authoritative account. In the case of this thesis, the authoritative account in question is the data visualisation of the as- sessment reports of the IPCC. Discourse is expressed through images, texts, and practices (any and all of these are legitimate sources of analysis). The sole focus of this investigation are images. Within the conventions of a discourse analysis, it is acceptable for sources to sometimes be eclectically assembled, this might be un- conventional in some qualitative research approaches in both the humanities and in the social sciences, but this is demanded by the intertextual nature of a discourse analysis method. A key concept to be defined in this section of the thesis is that of a “dis- course”. What is a discourse? A discourse might be understood as a coherent pattern of statements across a range of archives and sites (Green 1990, p.3). The wider the range of archives/sites the better the analysis. The most interesting discourse anal- yses bring together previously disparate materials (Rose 2001, p.143), and it is for this reason that this analysis not only draws on visualisations from the IPCC reports for interpretive materials. In addition to the systematically assembled IPCC visual- isations, this dataset is supplemented by the “eclectically assembled” climate-cen- tric data visualisations from other sites. Primarily journalism and more Avant Garde examples of scientific data visualisation. On the selection of materials for conduct- ing a discourse analysis, an emphasis should be placed on quality over quantity (Tonkiss 1998, p.410). For the purposes of this thesis, a selection has been made from all possible sources of a few supplementary materials that presented them- selves as interesting to the researcher as an individual, and with the primary dataset of the IPCC visualisations in mind for which they made for compelling materials to compare and contrast with. Discourse analysis explores how these specific views or accounts are con- structed as real or truthful or natural through particular regimes of truth. Discourse is organised in order to be persuasive; discourse analysis focuses on the strategies of persuasion. The primary interpretive tool for investigation in discourse analysis is intertextuality. A search for recurring themes is common in discourse analysis. With intertextuality depended on for interpretive power. It is through the composi- tions, characteristics, and meanings of elements of the discourse and those of neigh- bouring discourses that serve to illuminate the meanings of those being analysed. One illuminates the other, and the meaning or power of a discourse is formed by the mutual reinforcements of the other elements. With that being said, because – according to theorists and practitioners of discourse analysis – all knowledge is produced through the formation of a discourse, and all discourse analysis must be conducted to some extent utilising prior knowledge to inform the interpretation, it
16 is difficult for a researcher to sit outside of the system and view it with “fresh eyes” or a sense of objectivity. Therefore, there is an extent to which discourse analysis relies on “common sense” interpretations. This is a difficult methodological process to describe. Foucault outlines the approach by stating that pre-existing impressions ‘must be held in suspense. They must not be rejected definitively, of course, but the tranquillity with which they are accepted must be disturbed; we must show that they do not come about by themselves, but are always the result of a construction the rules of which must be known and the justifications of which must be scrutinized’ (Foucault 1972, p.25). When approaching a discourse analysis methodologically, Tonkiss (1998, p.414-5) suggests dividing the investigation into two main areas of analysis. The first is an analysis of the structure of the discourse statements themselves. For the purposes of this thesis, the – presumably conventionally textual – “statements” will be substituted for the visual objects, and by their “structure” this thesis will under- stand that to mean the compositionality of the images in this context. The second is an attempt to problematise the social context of those statements. To ask questions regarding who is saying them and in what circumstances? In addition to Tonkiss’ two areas of analysis, this thesis will also consider the technological circumstances and limitations of the visualisations’ production, since this can be a significant fac- tor in the resulting images. The IPCC is an intergovernmental organisation of high international standing, which does not conduct its own research but instead synthesises the findings of actors in the field to produce assessment reports. The discourse they produce is operating within the parameters of the natural sciences, but also at a boundary or a meeting place between scientific research and international politics. Within this context this thesis must attempt to understand how this particular discourse is struc- tured and how it produces a certain kind of knowledge. In order to understand how a discourse produces meaning it is important to understand how it describes things. This is where the formative power of a discourse lies. Therefore, the key methodo- logical practice of this thesis is to unpack how the IPCC visually describes its sub- ject, how does this particular discourse describe things? For a discourse the act of describing is the act of making something real (Rose 2001, p.150) and discourse analysis, therefore, takes a constructionist view of the world. Discourse analysis takes a somewhat unconventional approach to truth claims. The practice aims to be persuasive rather than truthful or rather than making claims to some unquestionable truth. As a result, practitioners should embody a certain modesty in their analytical claims (Tonkiss 1998, p.260). That is not to say that discourse analysts are absolved of any requirement to reflect critically on their own research practices. The problem for reflexivity in discourse analysis is that reflexivity is a mechanism for fields or disciplines whose research claims to have ascertained some kind of objective truth. Discourse analysis does not do this since
17 it rejects the idea of objective truth as a concept. Therefore, it would be logically inconsistent to engage in a reflexive practice when the entire paradigm of the prac- tice is centred around the idea that any analysis can only be tied to the specific researcher in question and the discourse they operate within. The work of a dis- course analyst ‘seeks to open up statements to challenge, interrogate taken-for- granted meanings, and disturb easy claims to objectivity in the texts they are read- ing. It would therefore be inconsistent to contend that the analyst’s own discourse was itself wholly objective, factual or generally true’ (Tonkiss 1998, p.259). In line with the mode of approach to the notion of reflexivity, this investigation presents its findings as originating from the interpretive perspective of the individual re- searcher, and acknowledges that another researcher may identify different materials in which to contextualise the empirical data, and may well come to different inter- pretive conclusions, and that the existence of two forms of interpretation need not invalidate each other. This modesty is discourse analysis’s substitute for reflexivity.
Theory Does an image such as the graphical representation of scientific research data require a different analytical approach to that which might be employed to interpret a more traditional visual study object, such as a painting from one of the old mas- ters, or a sculpture by Picasso? This thesis says no. That the same humanistic ap- proach to interrogating the meaning of a painting, sculpture or piece of architecture can also be employed in excavating the meaning of a graph or chart. This thesis makes no claims to objective truth or knowledge. The problem of ascribing meaning to images is that the analysis of images is necessarily interpretive and informed by the subjective view of the researcher (Hall, 1997, p.9). Therefore, my interpretation of the empirical objects of this study is entirely my own, and it is perfectly possible that someone else conducting the same work may come to entirely different con- clusions. For this reason, the interpretive power of this thesis lies in the use of crit- ical intertextuality, to compare and contrast a primary set of data with a secondary set, to do the work of describing rather than to make any claims of delving beneath the surface or discovering any meaning which is hidden. The meaning on the sur- face provides sufficient material for critical engagement. When engaging in an interpretive analysis of a set of images, it is important to do so with the aim of addressing questions around cultural meaning and power, rather than merely giving consideration to aesthetic qualities for the sake of it. The focus of this analysis will be on how scientific data visualisations often conform to aesthetic principles that project notions of power and authority or accuracy, through the misplaced trust in objects that are aesthetically minimalist. This standard of presentation is common in the natural sciences and projects an air of objectivity and accuracy that is not necessarily present.
18 For the purposes of this thesis, the choice was made to employ a qualitative rather than a quantitative approach, with an emphasis on curating a manageable collection of interpretively engaging visual objects. Among which can be identified a recurring set of visual patterns and themes can be identified, which can be ana- lysed and understand to form a coherent narrative. While quantitative methods can be deployed effectively in the analysis of visual images; such as those, for example, developed by Lev Manovich, among others. These qualitative methods take huge corpuses of film or photographs to produce composite images or structured data- bases in order to take a broad overview of the empirical materials, an approach Manovich terms Cultural Analytics. However, this thesis’ emphasis on exploring the meaning of these objects and the trends identified among them suggests that qualitative methods are more appropriate, a critical close reading of select objects rather than a distanced overviewing of a dataset. The interpretive approach of this piece of work is informed in great part by the work on visual methodologies by Gillian Rose (2001). Rose’s suggestion that successful interpretation of visual images depends on a passionate engagement with what you are looking at, rather than strict adherence to a specific method, has been instrumental to the work carried out here. While this thesis does have a specified methodological and theoretical approach, exploring thematic intertextual connec- tions and excavating the potential meaning of these objects has been prioritised over sticking rigidly to a predetermined methodological framework that does not per- fectly fit the materials or the aims of the thesis. Sitting as it does at the boundary between a number of different/disparate disciplines, fields, or topics: discourse analysis, visual culture, information aesthetics, and the topic (rather than practice) of climate science. There is a necessity to adopt a flexible, adaptable approach ra- ther than a rigid framework. A central aim of this discourse analysis is to describe in order to better under- stand the “visual culture” of data visualisation in climate science. In this sense, this work is in line with the “cultural turn” in the social sciences. Within this context the word “culture” has a specific meaning, which for the purposes of this thesis is a concept worth defining. Culture can be understood as ‘the ways in which social life is constructed through the ideas that people have about it, and the practices that flow from those ideas’ (Rose 2001, p.5), culture is what Stuart Hall (1997, p.2) referred to as ‘a process, a set of practices.’ These definitions have echoes of the work of Bruno Latour and Steve Woolgar (1986, p.45) and their descriptions of life in a laboratory as a set of practices and processes centred on writing and documen- tation in which scientific truths are socially constructed within the laboratory itself, by its practitioners, rather than through some unbiased mechanism for attaining truth and accuracy that might be called the scientific method. This forms the basis of a theoretical assumption of this thesis, which is that scientific knowledge centred on the Earth’s climate is a social construct of the field’s research practitioners who
19 construct it through the formation of a discourse. This discourse presents a way of viewing the world through the construction of meaning, these constructed meanings in turn inform peoples’ behaviour. Everything is constructed – especially images – and these constructed images render the world into visual terms, on the terms of those doing the constructing. Ideas of both photographs and graphical visualisations of data (and data itself) as being objective presentations of the world, as being transparent windows framing reality, have for a long time been considered naïve (Rose 2001, p.7; Healy 2019, p.23). Both interpret the world – or interpret data in the case of data visualisation – and display it in a particular way that is chosen by the author (or by the invisible conformity demanding power of “discourse”), dictated by technological con- straints, or interpreted by the audience. This study is concerned with the visuality – or scopic regime – surrounding climate science data visualisation. To define these two terms: visuality refers to how what we see is culturally constructed, ‘how we see, how we are able, allowed, or made to see, and how we see this seeing and the unseeing therein’ (Foster 1988, p.ix). Scopic regime is a term that is frequently used interchangeably with visuality, but seems to be generally used with a greater emphasis on the role of discourse; ‘[b]oth terms refer to the ways in which both what is seen and how it is seen are culturally constructed’ (Rose 2001, p.6). One theoretical pillar of this thesis is a consideration for how this relationship between looking, seeing, and knowing has been viewed historically. Interrogating this relationship is an important factor in understanding the meaning of these IPCC data visualisations, and so, it is important to unpack the theoretical progression of how scholars have thought about looking, seeing, and knowing. For some thinkers, there was – and perhaps still is – a regard for “seeing” as being the most primal form of reading (Berger, 1972, p.3). Within the context of this thesis, this is im- portant because an aspect of an object’s visuality which contributes to its meaning is how it is interpreted by a viewing audience. This idea of seeing by the likes of Berger as somehow primal and innate begs the question of how conscious the au- dience is of their own seeing and interpretation. Is there reason to suggest the read- ing of images critically is a skill that is less well practiced by people because it is seen as easy or simple because of its primality? More so than reading text, which comes later in human intellectual development? The viewing of images is often done more passively than reading text, which is a more active process. Does this affect how we think about images? Particularly when considering audience and meaning making. As a result of the somewhat frequent conflation between “look- ing”, “seeing”, and “knowing”, Jenks (1995, p.3) expounds upon these three activ- ities and how these words have sometimes been used synonymously, why they should not be, and how these things have changed over time or at times been con- fused in western culture. Martin Jay (1993) argues for historicising the
20 ocularcentrism, or the importance of “the visual”, in western culture. Stating that the compression of looking, seeing, and knowing into the same thing has been a cultural phenomenon since the Enlightenment. Barbara Maria Stafford (1991, p.2) says that, since the 18th century, construction of scientific knowledge has become increasingly visual and less written. This work presents an argument in favour of privileging the visual elements of scientific literature over its text, which this thesis adopts as a key motivation for scrutinising solely the images of a scientific organi- sation and paying little attention to its text as it views the visual as the IPCC reports’ most important elements. There is some debate over whether our contemporary society is visual or post- visual, ocularcentric or post-ocularcentric, in its view of the visual; whether we equate looking and seeing with knowing, or whether our relationship with images is much more sceptical. Guy Debord (1983, p.10) described the 20th century as the “society of the spectacle”. A society devoted to the visual that privileged it as a medium above all else. This may well have been the case for the previous century and could also be the case for this current century. If it is indeed the case, then it is all the more necessary to interrogate the visual elements in particular of this cen- tury’s most pressing, existential problem: climate change. Problematic, then, is the point which Mirzoeff (1998, p.4) argues that ‘the postmodern is a visual culture’ too, but that the modernist relationship between seeing and true knowing has been broken. No longer is the visual a straightforward presentation of reality, but instead a representation articulated from a certain perspective. This casts doubt on the rela- tionship in previous centuries between seeing and knowing and presents the visual as persuasive rather than illustrative. This relates to what Jean Baudrillard (1988, p.166) dubbed the simulacrum, that it is no longer possible to distinguish between real and unreal images, that we now live in a scopic regime dominated by “simulations”. (This may perhaps be taking things a bit too far, provenance can help to distinguish real and unreal, but there is certainly a seed of an idea here that can be expounded upon.) This proposi- tion may be something of an outlandish stretch if applied to our collective reality, but there is a potential to apply this mode of thinking to certain areas of human culture. In the case of those “hard disciplines” such as the natural sciences, which the work of the IPCC is situated within, this concept of visual objects functioning as a proxy for the real thing is an often unreflected-upon assumption. That the visual representation of the data, even the data itself, is an objective signifier reflecting reality – this thesis claims – is a dangerous philosophical assumption and should be challenged in all disciplines. This problem has been identified by Haraway (1991, p.188), among others, who view images as producing specific visions of social dif- ference and the “reality” of the world, while itself claiming not to be part of that hierarchy and thus to be universal.
21 This thesis is concerned with the visual culture of climate change as exhibited in the IPCC’s assessment reports, but Rose (2001, p.10) warns that “Visual Culture” is not a phrase to be used carelessly, and there is some debate over the usefulness of the term. Aspects of visual culture this thesis will be considering include: the idea that images themselves ‘do something’ (Rose 2001, p.10), that the act of visu- alising is powerful because it has the capacity to mould reality and our understand- ing of the world around us; that images have the capacity to visualise, but also to render invisible (Fyfe & Law 1988, p.1), and that we should scrutinise what is ab- sent as well as what is present; that the audience is also important and we should be concerned both with how images look, but also how they are looked at (Berger 1972, p.9). When approaching a visual analysis of empirical materials methodology, it is productive for the investigation to delineate between three different sites for analy- sis in order to engage with one of them in a comprehensive and thorough manner. Analyses that neglect to delimit the study in this way risk a degree of analytical incoherence and reduce the extent to which they can engage with their object of study. The three image sites under consideration are: the site of the image’s produc- tion, the image itself, and the viewing audience. This approach is outlined in detail in Rose (2001, p.16). Rose states that any one of these three sites may provide a stable interpretive platform from which to explore the meaning of the empirical data. In the context of this study, broadly speaking, the site of the image’s produc- tion is by the researcher who contributed to the assessment report; however, this is always in consultation with, and in-line with the visual presentation guidelines of the IPCC. Meaning that the site of the images production in generally within natural science departments of global research institutions and the IPCC itself. The viewing audience as an interpretive site is somewhat broad, encompassing the scientific community itself, policymakers, activists, general readers, and scholars in other dis- ciplines to name just a few. This thesis will give some consideration to this partic- ular site, focusing generally on the scientific community and policymakers. But the primary site of interest in this investigation is the site of the image itself. The images themselves are varied in nature and naturally difficult to summarise here, much of the impetrative effort and the majority of the empirical part of this thesis is dedi- cated to unpacking these aspects of the dataset. These sites are made complicated by the existence of a set of modalities which of three different dimensions from which a site can be considered, these modalities are: the technological, the compo- sitional, and the social. This thesis will consider all three of these modalities. For the technological, the analysis will consider what Paul Virilio (1994, p.59) called the “vision machine” in referring to the new visualisation technologies of computers that emerged in the later part of the 20th and made computer generated data visualisations accessible to
22 a wider audience, and how this affected the images featured in the IPCC reports. For the compositional, a great deal of analytical emphasis will be placed on the composition of the images themselves, considering formal strategies such as the content, colour, and spatial organisation of the elements that make up the visualisa- tions. And finally, for the social modality, the analysis will give some consideration to the social context in which the images are produced, the potential audience that could be viewing it, the designed and real effects the discourse produces in the so- cial world. In dealing with climate science graphs as an object for humanistic study, it is likely important to address a question of genre. In the context of this thesis, data visualisation will be considered as a specific genre of visual object (and climate change data visualisation as a sub-genre); with various types of graph – line, bar, pie – the forms that exist within the genre. Compositionality: composition of image greatly informs ways of seeing and understanding it (Pollock 1988, p.85). Alternatively, John Fiske (1992, p.345) sees the audience as the most important factor in meaning making and this explains the changeability or instability of image meaning. There is a tension between audienc- ing and compositionality for importance in meaning making. In reality it is probably a much more fluid and nuanced reality for which is most important for meaning making. The composition obviously informs how an image is understood, but the creator almost certainly had an audience in mind when making the image, so they probably composed the image in a certain way to communicate something specific to a certain audience, who in turn understood it in a certain way because of the composition. The reality is that they are all part of a particular discourse, which covers both bases. Fiske regards both as being part of the same ecosystem.
Materials The materials which form the focus of this study are all some form of visual- isation of scientific information relating to climate change. These materials have been resourced from two distinct sets of data. The primary set originate from the first five assessment reports of the IPCC. These are the reports produced by the IPCC, which is an intergovernmental organisation formed through a partnership between the United Nations (UN) and the World Meteorological Organization (WMO). The IPCC has produced five full assessment reports in the years 1990, 1994, 2001, 2007, and 2014; with a number of special and supplementary reports in 1992, 1994, 1997, 1999, 2000, 2005, 2011, 2012, 2018, and 2019. A new report is expected to be published in 2022. For the purposes of this thesis, only data visu- alisations from the five full assessment reports will be considered for analysis, with only a brief comment in the cover of the 1992 supplementary report. The analysis discusses the largest number and broadest range of the images included in the
23 assessment reports. However, for reasons of brevity, a desire to interrogate thor- oughly a smaller data set rather than only covering the surface of a larger group, and because some examples were so similar that it did not make sense to go over the same ground twice, not all images are included and discussed. The secondary set of data is more selective and fragmented in nature, com- prising a curated collection of extra-scientific examples of climate change data vis- ualisation. The examples in this set of data were selected and curated to give further context to the primary data. The curation was done on the basis that certain images are especially iconic, representative, or commonly recurring in the general discus- sion on climate change, while also in obvious communication with the primary data, by being comparable, contrastable or echoing the visual style of the IPCC examples. Thus, revealing the connections between the specific visual culture of the IPCC reports and the general visual culture of climate change.
Relevance and Topicality The ecological effects of the changing climate are an ongoing threat and cause of damage to our planet. The evidence of the existence of the problem we call cli- mate change has never been more abundant, well founded, and convincing. Yet we find ourselves in a position where despite the plethora of evidence and the convic- tion of the scientific community, there is little being done to address the problem on a political or societal level. There exists a problem of scientific communication on the topic of climate change. This is something the IPCC itself has highlighted. They admit that ‘[l]ittle evaluation has been done of visualization projects, therefore leaving a gap in un- derstanding of how to most effectively communicate future risks of extreme events’ (IPCC 2012, p.302). Work needs to be done and research synthesised from a broad range of disci- plines: including the natural sciences, social sciences, and the humanities, in order that we can better understand the problem of climate science communication and manifest a solution. It is the humanistic aspect of this work that this thesis aims to be a small part of.
24 Development and Variation in IPCC Data Visual- isation
This first section will focus entirely on the climate science data visualisations fea- tured in the first five IPCC assessment reports, describing the visuality of these objects and tracking their development, variations, and consistencies. The infor- mation aesthetics of these reports has a direct impact on the efficiency of the infor- mation communication which is taking place. This section aims to describe the de- velopment of the reports’ information aesthetics in order to analyse key features of the reports’ visualisations in subsequent sections. This section will focus on several aspects of the IPCC reports’ visual culture. This includes the introduction and use of colour from the second report (1994) and how this developed throughout subsequent reports (2001-2014). It also includes graphical forms that have been used consistently throughout the different reports, and those that have faded away or been used intermittently. This section will addi- tionally comment on the increased complexity of the images contained in the re- ports, what communicative or technical reasons there may be for this, and whether it serves to improve the effectiveness of the communication, or whether readability is compromised as a result. A recurring form that does not receive its own section later in this thesis is the use of a 2D representation of the globe. This is a repeated form that shows a pattern of use and deserves some analysis, but is not significant enough to warrant its own section; therefore, this section has a short note on its use. This section will mainly focus on the ‘image itself’ (Rose 2001, p.16) as the analysis site, in which the assessment reports of the IPCC have exhibited a range of different data visualisation compositional forms. Some of these forms have formed consistent through-lines – or a scopic regime – in the visual representations of the research presented in the reports, with subtle variations in use of colour or the visual complexity of the form, but with none-the-less a consistency in their use. While others can be seen as transitional or experimental forms, those which are used spar- ingly are unique, or have been phased out to allow for the dominance of certain perennial forms. A visual aspect of the IPCC assessment reports, which is interesting to track the development and variations of, is the reports’ front covers. The choice of image for the reports’ cover is important because it is the first thing anyone who reads it will see, and therefore it is important in that it has the capacity to communicate something essential about the report’s contents. Frequently, the report’s front cover serves to communicate the broader message of the contents of the report. Discussion of the front covers will also form part of this section.
25 These forms of visual information representation – the graphs and the covers – demonstrate conscious choices on behalf of the authors of the reports and raise questions about the effectiveness of these forms in their ability to communicate the content of the reports and make an argument for implementing their recommenda- tions. Why, for example, does the IPCC make such persistent and prominent use of line graphs, while the use of pie charts was fleetingly brief? Is there a rationale for the reports’ tendency to restrain itself to familiar data visualisation forms – such as bar graphs and pie charts – rather than more experimental forms? And what is there to be said about the increased complexity of the graphical forms included in pro- gressive reports? Is this due to improved technological possibilities, and if so, does this shift make the communication more effective or more confused?
First Assessment Report (1990) In this first instance of an assessment report from the IPCC there is also the first example of the use of visual representations of data and scientific findings to sup- plement the text of the report and assist in the explanation and argumentation of the organisation’s report. We will come to see that the use of visual objects by report authors is a consistent element in the assessment reports that have been produced so far. Some elements of the visual images will change over the course of the five assessment reports, while others will remain consistent features. These develop- ments and variations can be a result of conscious choices on the part of the authors, or it can be a result of technological developments that alter what is possible for the report. This section will begin by giving a broad overview of the characteristics of the visualisations featured in this first report. The first, most striking, characteristic is a complete absence of colour. The visuals are monochromatic, with only a small amount of shading. We see the first instances of forms that will become familiar in the course of subsequent reports, such as line graphs and a map of the Earth’s pro- jection; as well as some lesser used forms such as pie charts and the only instance of an explanatory diagram. The use of colour in IPCC assessment reports will form a major topic of in- terest for this thesis. However, there is little to remark upon here since there is no colour in any of the visualisations. This is likely a result of technical limitations. The methods of preparing and publishing the report itself may not have supported colour printing, and therefore the lack of colour is a pragmatic choice rather than a conscious decision. The introduction of colour in later reports is likely to have been the result of an increased availability of computational methods to produce colour data visualisations and to colour them; or more affordable means to print in colour. The increased availably and affordability of personal computers capable of enabling professional standard desktop publishing throughout the 1970s and 1980s achieved
26 a critical mass of desktop publishing technology in the 1990s that would have af- forded the reports’ authors the opportunity to control the entire design process (Grad & Hemmendinger 2019, p.6). The original lack of colour in the first assess- ment report may also have been a budgetary issue for this fledgling organisation, which may not have been able to afford costly colour printing. What we do encounter the first examples of – which will be explored in some detail in later sections – is a simplified form of upward trending line graphs. The versions of this visual form, which will recurringly feature in IPCC assessment re- ports, are simple and plain in comparison to later iterations. Sometimes featuring only a single line plotted across a blank white background. What is remarkable about the fourteen instances of line graph used in this report, is that the lines almost all trend upwards. With a couple of instances of flat lines and the odd downward line, the overwhelming trend is towards upward lines. This is an interesting quirk of the first report and one that we will see repeated again and again in IPCC reports. The significance of this observation is the focus of the third section of this empirical part of the thesis. These line graphs usually include projections for what is likely to happen in the future to the climate depending on different scenarios (future predic- tions which are conspicuously absent in visualisations produced outside of the sci- entific community).
Fig. 1: [Original caption] “Simulation of the increase in global mean temperature from 1850- 1990 due to observed increases in greenhouse gasses, and predictions of the rise between 1990 and 2100 resulting from the Business-as-Usual emissions.” Source: IPCC, 1990, Climate Change: The IPCC Scientific Assessment, Cambridge University Press, Cambridge, p.xxii.
The first report also features certain forms that do not feature in subsequent reports or feature very rarely. The first is an explanatory diagram of the “Green- house Effect” and how it works. This is the only instance of an infographic visual form that explains a process, rather than representing statistical data. It is curious that this form of visual communication is featured then abandoned so early in the series of assessment reports. It is perhaps indicative of the tone the reports have attempted to strike, an explanatory infographic is perhaps too pedagogical and not
27 purely scientific enough. This early report set out to establish a connection between human activities and global warming, which it successfully did, and subsequent reports have sought to supplement that case with further evidence. Therefore, the IPCC may have considered the task of communicating the central phenomenon complete after the first report, and for that reason this is the only one with such pedagogical material.
Fig. 2: [Original caption] “A simplified diagram illustrating the greenhouse effect.” Source: IPCC, 1990, Climate Change: The IPCC Scientific Assessment, Cambridge University Press, Cambridge, p.xiv.
The first assessment report cover makes some of the least effective, or at least the least obvious, use of this capacity to communicate the essential message of the report itself in the cover image. The cover depicts a coastal scene, with a setting (or perhaps rising) sun which illuminates a cluster of varied cloud types. Cloud types are of longstanding metrological interest, and the image seems to encompass the sphere of interest for climate studies, since this complex system involves or effects both the land, ocean, and the Earth’s atmosphere. The only possible symbolic aspect of the cover is the image of a setting sun, which perhaps emphasises the message that time is of the essence, and quickly dissipating.
28
Figs. 3 and 4: The front covers of the 1990 IPCC Scientific Report and the 1992 IPCC Supplemen- tary Report.
Supplementary Report (1992) The supplementary report released in-between the first and second assessment re- ports exhibits a cover image which is much more pointed in its meaning. Seeming to rely less on symbolism – if the symbolism read into the first report’s cover image is correct – the supplementary report cover image communicates much more clearly the real-world consequences of a changing climate. The floating sea ice, which – as with the setting sun in the previous report – one can almost imagine floating away from the viewer. Shrinking into the distance and shrinking in size because of warm- ing temperatures. The land in the foreground one might assume after reading the report was previously covered in snow and ice that has since melted. Again, the image incorporates climate research’s principal objects of study: atmosphere, ocean, and land. Finally, the person in a small boat, moving across the image from left to right, shows the small human scale of the problem, that humans are relatively small organisms compared to the scale of a planet and that we are inflicting dispro- portional damage on the climate.
Second Assessment Report (1994) The second assessment report saw a partial shift towards colour; but with a limited, perhaps again technologically constrained colour palette. In terms of form, we see the establishment of the line graph as a dominant visual form, alongside the intro- duction of a segmented line graph. Again, we have a map of the Earth.
29 Fig. 5: The front cover of the 1994 IPCC assessment report.
The second assessment report cover again shows a departure from previous cover designs. Again, the message is much more explicit, with this cover instead placing great emphasis on the causes of the changes observed in the climate and reported in the report, rather than on the effects, as is the case in the 1992 supple- mentary report. This 1994 second report cover repeats the symbolism of the 1990 first report with a setting sun, but this is set behind the overriding image of a power plant out of which billows smoke from the plant’s chimneys and towers. The bil- lowing smoke replaces the scenic cloud formations of previous reports, emphasis- ing the shift in focus for the researchers away from a soft, delicate, and natural object of study which they previously worked with, only for this to be replaced with the toxic plumes of greenhouse gasses. The setting sun may also present a double symbolism. One is the previously alluded to lack of time left to act, but the other is that the IPCC is perhaps suggesting that the sun is or should be setting on the era of fossil fuels, that their findings show that these fuels and their emissions are so dam- aging that we can no longer go on using them.
Fig. 6: [Original caption] “Carbon dioxide emissions leading to stabilization at concentrations of 450, 550, 650, 750 and 1000 ppmv following the profiles shown in (a) from a mid-range carbon cycle model. Results from other models could differ from those presented here by up to
30 approximately ± 15%. For comparison, the carbon dioxide emissions for IS92a and current emis- sions (fine solid line) are also shown.” Source: IPCC, 1994, Climate Change 1994: Radiative Forcing of Climate Change and An Evaluation of the IPCC IS92 Emission Scenarios, Cambridge University Press, Cambridge, p.10.
The line graphs in the second assessment report represent a departure from a key feature of line graphs from the previous report and from what we will see in subsequent reports. That is the frequent use of downward trending lines. Interest- ingly, these lines are not used for representing observed data, but instead are de- ployed in order to express future possibilities. In this sense the visual tone of the second IPCC report is more optimistic than the first, and perhaps more optimistic than any subsequent report. If the aim of the report is to execute effective scientific communication in order to produce change in society, the first report is perhaps slightly too pessimistic, presenting a vision of the future too bleak to affect positive changes. This second report presents a series of potential future scenarios that all show the possibility of hope and redemption, should society choose the right sce- nario. Which is overwhelmingly more positive. The introduction of colour into the visual culture of IPCC reports show a movement towards what will be a permanent feature of future reports with the pres- ence of colour, however the use of colour is restricted to a few shades of blue which are difficult to implement strategically for the purposes of persuasion or meaning- making. Instead, colours are generally used to differentiate between different ele- ments within a form, rather than being employed to evoke cultural or psychological responses. This characteristic of the second report’s visualisations also bucks a trend that will emerge in the IPCC reports and even more so in the wider climate change discourse, which is the prominent use of red to communicate heat and dan- ger.
Fig. 7: [Original caption] “Global energy-related CO2 emissions by major world region in GtC/yr. Sources: Keeling, 1994; Marland et al., 1994; Grübler and Nakicenovic, 1992; Etemad and Luciani, 1991; Fujii, 1990; UN, 1952.” Source: IPCC, 1994, Climate Change 1994: Radia- tive Forcing of Climate Change and An Evaluation of the IPCC IS92 Emission Scenarios, Cam- bridge University Press, Cambridge, p.37.
31
The visualisations in the second report represent an increase in complexity when compared to the extremely simple forms featured in the first report. This in- crease, however, does not serve to compromise the readability of the objects; in- stead, the result is an increased efficiency of the objects, with often more infor- mation contained within a single object than was the case in the first report.
Third Assessment Report (2001)
The visual suite of the third assessment report sees the emergence of what will be- come the established colour form in IPCC reports, with the continued use of line graphs as the most dominant form. The line graphs display a further increase in complexity, continuing a trend from the two previous reports. Again, we see the use of a single globe projection map. Both the third and fifth assessment reports use composite images imposed onto a blue background. The 2001 report shows the Earth, surrounded by images of environments or ecosystems likely to be affected by a changing climate. The 2014 report elaborates on this theme, again displaying images of places likely to be af- fected by climate change alongside a cityscape, with urbanisation an important driver of a changing climate. These are shown within a circle, with jigsaw puzzle piece-like edges, that communicate a complexity to the problem, and also a sense of factors in the problem being interrelated.
Fig. 8 (left): The front cover of the 2001 IPCC Synthesis Report. Fig. 9 (right): The front cover of the 2014 IPCC Synthesis Report.
32 The introduction of a full colour palette adds a further level of complexity to the images, further differentiation between lines or gradiation between sections of maps. The use of the colour red is present for the first time in an IPCC report, which is an element of climate change discourse and visual culture this is highlighted in this thesis as an important recurring feature. But the colour is not used quite to the persuasive effect that it has been used elsewhere, instead it is often used simply as part of a palette of sharply contrasting colour options that help the reader to differ- entiate between visual elements. We do find some use of the colour, however, that could be cited as effective use of its properties. Figure 10 shows the first tentative uses of the colour to denote dangerous or working phenomena represented in graph- ical form.
Fig. 10: [Original Caption] “Variations of the Earth’s surface temperature: years 1000 to 2100.” Source: IPCC, 2001, Climate Change 2001: Synthesis Report, Cambridge University Press, Cam- bridge, p.34.
We also see the first appearance of possibly the most central visual form in climate change discourse: the “Hockey Stick” graph. An entire section of this thesis is dedicated to analysing the “Hockey Stick” graph and its story, so it will not be discussed in too much detail here. But what is interesting is that the graph does not originate from the third assessment report – it was published in a scientific paper some time before the IPCC report was devised and incorporated as part of the re- search the IPCC collates, as is their purpose – and it went on to take on a life of its own, emerging in popular culture and in political and scientific discourses both
33 supporting and aiming to discredit anthropogenic climate change. The role of the IPCC report in this story of the “Hockey Stick” graph is interesting, because the report served as a catalyst to promote the graph into the wider world and the sur- rounding discourse as a central image. Within the broader discourse on climate change and anthropogenic global warming, the IPCC is an authoritative focal point as the discourse’s central institution. The power the IPCC has in curating the most recent, relevant, and rigorous scientific research on this topic and to promote it in wider society is demonstrated by the story of the “Hockey Stick”.
Fourth Assessment Report (2007) The visual suite of the fourth assessment report shows a continuation of much of the themes that established themselves in the third report and which will continue into the future. Again, we see prominent use of a high contrast colour palette. Line graphs are also used prominently, but the extent to which they make up the majority of the forms has eased, with the use of bar graphs, (the re-emergence of) pie charts, and world maps featuring much more prominently than in previous reports. The cover image of the fourth assessment report offers little to interpret. It depicts a simple line drawing of a world map in white on a blue background. There is little to be read into the use of this image for the cover, so little space will be devoted interpreting it here. However, some space is dedicated later in this section on the repeated use of a flat 2-dimensional projection of the globe as a perennial visual form in IPCC reports.
Fig. 11: The front cover of the 2007 IPCC Synthesis Report.
34 The inclusion of composite images that mix the forms that have previously featured in reports is a new development. Particularly the use of line graphs over different regions of a world map helps to communicate the different impacts of cli- mate change on different geographical areas. These images strike a balance between complexity and understandability, not being so elaborate that the meaning becomes convoluted, and effectively communicating the segmented data. This is an im- portant feature of this report, since the problem of climate change affects different regions to differing extents, so the ability to communicate that fact is crucial.
Fig. 12: [Original Caption] “Comparison of observed continental- and global-scale changes in surface temperature with results simulated by climate models using either natural or both natural and anthropogenic forcings. Decadal averages of observations are shown for the period 1906- 2005 (black line) plotted against the centre of the decade and relative to the corresponding aver- age for the period 1901-1950. Lines are dashed where spatial coverage is less than 50%. Blue shaded bands show the 5 to 95% range for 19 simulations from five climate models using only the natural forcings due to solar activity and volcanoes. Red shaded bands show the 5 to 95% range for 58 simulations from 14 climate models using both natural and anthropogenic forcings.” Source: IPCC, 2007, Climate Change 2007: Synthesis Report, Cambridge University Press, Cam- bridge, p.6.
The extent to which colour is utilised strategically also increased in this report compared to those published before. Particularly the use of red in highlighting ge- ographical areas affected by global heating and in referring to the impact of anthro- pogenic factors in line graphs representing heating. Blue is also featured notably to indicate those graphs that are communicating issues on rising sea levels. That being said, pointed use of colour is still relatively limited, compared to that exhibited by non-IPCC visualisations (which will be discussed in a later section).
35 Fifth Assessment Report (2014) In the fifth assessment report we have the most recent iteration of the IPCC’s visual style. Once again, we find familiar graphical forms in line graphs, globe projections, and stacked line graphs. The use of colour is again more strategic than the previous iteration. The suite of images adheres more strictly to these tried and tested visual forms, with bar graphs and pie charts being side-lined almost entirely. In the instances of line and stacked line graphs we find very much the contin- uation of a well-established trend of upward trending lines, with very seldom in- stances of lines trending downwards. Previous reports have made extensive use of line graphs which predict potential future scenarios, which this report engages in but to a much lesser degree. The use of colour is again much more considered and strategic. The use of a green colour palette for greenhouse gases is effective in telegraphing the subject of the graph. The use of red is again used to good effect to highlight the most concern- ing, and most related to heat, elements. Again, blue is used to illustrate rising sea levels to great effect, not only is blue an obviously good choice of a sea level rep- resentation, but again the upward trending aspect of the graph further illustrates the point.
Fig. 13: [Original caption] “Projected surface temperature changes for the late 21st century (2090-2099). The map shows the multi-AOGCM average projection for the A1B SRES scenario. Temperatures are relative to the period 1980-1999.” Source: IPCC, 2007, Climate Change 2007: Synthesis Report, Cambridge University Press, Cambridge, p.9.
36 A note on two-dimensional globe projections Representations of the globe in two dimensions has been a consistently employed data-visual object in IPCC assessment reports, appearing in each report at least once. This fact presents an important consideration for science communication and the tension between presentation vs. representation in science. The surface of a sphere cannot be represented as a plain without some amount of distortion, a math- ematical fact first proposed by Carl Friedrich Gauss. Therefore, a process of carto- graphic projection is required. Early IPCC assessment reports appear to use some version of the rectangular-edged Gall-Peters projection in lieu of the previously popular Mercator projection, which was useful for maritime navigation before sat- ellite navigation became widely available. Later reports have tended to favour the Winkel Tripel projection, which exhibits a pleasing compromise between distortion of either shape or size. The Mercator projection has been criticised by cartographers because of its distortion of the relative size of the objects represented in order to preserve relative shape. This tendency has resulted in post-colonial criticisms of Mercator’s empha- sising of the size of countries in the northern hemisphere, while minimising the size of southern and equatorial countries (Huggan 2008, p.21). This is something that cartographers have sought to avoid in order to avoid reinforcing negative or dis- missive attitudes to the developing world. In addition, these areas of the world are those which are more likely to suffer the most serious consequences of anthropo- genic climate change. It is, therefore, all the more important for an organisation like the IPCC to use a projection that preserves the size of objects (and therefore the size of the problem), and not one that serves to minimise them.
Fig. 14: Distortion in the Mercator (left), Winkel Tripel (centre), and Gall-Peters (right) projec- tions. Source:Vox/Youtube.
The Gall-Peters projection tends to preserve relative size while compromising actual shape of the objects represented on the map. This is important for an inter- national organisation like the IPCC and for a global problem such as climate change because it is important to show the scale of the problem with a degree of accuracy in terms of which countries or which parts of the world are likely to be impacted most (Campbell-Lendrum & Corvalán 2007; Mendelsohn 2008).
37 After a brief period making use of Gall-Peters, the IPCC employs the com- promising Winkel Tripel projection. The name tripel (German for 'triple') refers to Winkel's goal of minimising the three kinds of distortion that occur, then projecting the surface of a sphere on to a plain: area, direction, and distance. The Winkel Tripel achieves a pleasing compromise between these three tensions, presenting a map that is familiar, that does not “feel” distorted while preserving some degree of relative size.
Recurring Colours: Prominence of the Colour Red
In discussing colour and its use in the context of data visualisation in the scientific reports of climate change, as is the focus of the following section, the intention is not to delve into the science of colour. The specifics of particular wavelengths or the physiology of the human eye, nor will much attention be paid to the precise but various nomenclature of colour. Though this section is likely dealing with innumer- able colours – or at least a catalogue of shades and tones of one or two particular colours – we will instead be operating with the ‘inadequate […] daily vocabulary’ (Albers 2013, p.3) of colour names. Which, for the purposes of this study, are cer- tainly adequate enough; and limiting the discussion to “reds” or “blues” rather than getting into specifics of tones, hues, or shades, will hopefully serve to aid the clarity of the discussion. The focus of this section is on the cultural significance, symbol- ism, and subliminality of colours, the impressions they make on the reader-viewer, and how these facts are used within this particular discourse to supplement the ar- gument being made. This section will discuss how and why certain colours are used in climate science data visualisation – with particular focus on the colour red – and attempt to unpack the cultural and symbolic significance of this colour choice and to rational- ise why red is used so prominently in climate change visual culture. This being the stated aim of the section, it is important to stress the tentativeness of any conclu- sions drawn in the course of the discussion. In human visual culture – much like many of the formal elements of visual culture – colour should be regarded as ‘the most relative medium in art’ (Albers 2013, p.71) and as a result ‘the same color [has the potential to] evoke innumerable readings’ (ibid). Variations in reading can depend upon the particular time and place the reader-viewer is situated in, with the cultural background of the viewer, their
38 individual cognition, and personal experience being among a variety of factors that can influence the way a particular visual object is understood. That being said, this section will attempt to make a sound argument on the cultural and symbolic mean- ings of particular colours. Focusing mainly on Western cultural norms but drawing on some universal human associations with the colour red also, in order to better understand the persuasive use of red in climate change data visualisations included in IPCC reports and to compare and contrast these uses with those of climate change data visualisations outside of the IPCC.
History and cultural associations The colour red is among the oldest colours to be isolated and utilised in human history (Marean et al. 2007, p.905; Pastoureau 2017, p.12), having been used in prehistoric art using pigments from crushed ochre. The colour has a long history of incorporation in human culture and brings with it long-established baggage of its symbolic significance and meaning. That is not to say that the meaning of red is not fluid or liable to change, as its cultural meaning and symbolism has shifted over time and differs according to geographical location. Until the introduction of synthetic dyes in the nineteenth century, red was rarer and more expensive to produce, and therefore had associations with wealth and prestige, often being used in ceremonial practices and a signifier of high-status and nobility. After the introduction of synthetic dyes, this association underwent a dramatic shift; moving away from the being the colour of nobility, red became the colour of the revolting masses. Shifting from an association with prestige and high status to an association with revolution; being the colour of blood, red became the colour of sacrifice and courage in the face of danger (Pastoureau 2017, p.163). The history of our cultural associations with the colour red are long and fa- miliar, but in a state of regular flux and liable to change. So, what can we say about the meaning and symbolism of the colour red in our contemporary culture? Is it as changeable as the colour’s history, or are there some consistent threads to draw upon? In one of the most comprehensive recent surveys of cultural and psycholog- ical associations of colours, Eva Heller (2009) explored the perception of the colour red among 2,000 German participants. Taking these findings to be reasonably rep- resentative of Western attitudes to colour in general, we find that – as Albers em- phasised – that perception of colour can be extremely variable, with the same colour being associated with concepts or phenomena that are diametrically opposed. Red can be mentally associated with danger, anger, and the presence of heat, on the more negative end of the spectrum; but also, more positive concepts such as love, passion, and wealth (Heller 2009, p.54; St. Clair 2016, p.136-7). The meaning that is drawn from interpreting the use of particular colours, much like the use of lan- guage, is likely to be incredibly dependent on the context in which it is used.
39 The variety of symbolisms associated with this ancient colour means that spe- cific symbolic meaning is difficult to pin down without reference to a specific con- text. The symbolisms and cultural meaning of a particular colour will always be multivalent and thus open to interpretation. So, the act of drawing an interpretive straight line between – for example – the use of the colour red and an intent to communicate danger or the presence of heat, is not an analytically straightforward proposition. Despite the variability of cultural meanings associated with the colour red, among the strongest psychological associations are danger, heat, and conflict (Heller 2009, p.54). In the face of these multitudes of meaning, this thesis argues that – in the context of the visual culture of climate science – it is reasonable to draw an interpretive conclusion on the use of the colour red as a cultural symbol and an attempt to communicate the urgency of a dangerous problem in which rising temperatures (heat) are an existential threat.
Infographics The cultural symbolism of the colour red as signifying danger or heat is reinforced by the psychological associations of the colour which were previously alluded to. In the field of ergonomics, or human factors, research has shown that red, of all colours, elicits the strongest reaction from viewers (Robertson 1996, p.148; Kar- wowski 2006, p.1518). The ergonomic use of the colour red to grab attention and to provoke action is well established. Having been used for a variety of communi- cative purposes to denote danger, to inspire caution or a change of behaviour in response to a threat, the consistent thread is the use of red for the highest level of threat or danger. Used routinely for traffic signals and hazardous materials or envi- ronments, red is also utilised in public safety materials. For example, the United States’ Department of Homeland Security uses red to denote the most serious terror threat level, while the UK NHS made use of the colour during the Covid-19 pan- demic to signify the most dangerous level of threat to the public and the health service.
Figs. 15, 16, 17, and 18: A regulation US traffic stop sign, a UK Health and Safety Executive warning sign, a UK Health Service COVID-19 poster, and a US DHS threat level chart.
40 Evident across all aspects of interpretive practice – across the culturally sym- bolic, the psychological and ergonomic – is that ‘clear reading depends on the recognition of context’ (Albers 2013, p.4); and the context in question for this par- ticular thesis is scholarly communication from climate scientists during a moment of crisis amid rising global temperatures. So, the use of the colour red in this con- text, taken together with the associated cultural baggage outlined in this section, indicates an increase in the aforementioned warming, rather than a cooling which might be – and often is – signified by blue (Heller 2009, p.14) as well as an indica- tion of danger and a need for action (Pastoureau 2017, p.178).
In (the English) language
There is something to be said even of the idiomatic use of the word “red” – in the English language at least – and reflections to be made on how these feed into the impression the reader-viewer has of visualisations that make heavy utilisation of this particular colour. Idiomatically speaking, the word does have some consistently negative connotations (Pastoureau 2017, p.52) that visualisations within this dis- course that do make use of it could be drawing upon. Negative emotional associa- tions such as the angry “to see red” or to “cross” or “draw” a “red line” suggest a need for a calming of a situation, which these visualisations may be subliminally attempting to communicate. Much of the discourse around climate change in gen- eral, and the arguments made by data visualisation of climate change in particular, is to communicate some kind of a warning to the reader-viewer; and so, the idio- matic raising of a “red flag” as a warning sign or as a means to indicate concern makes clear the purpose of the use of the colour red as a deliberate design choice. There are also more practical idiomatic examples, such as to “be in the red” in financial terms means to be in debt and to be operating at a deficit, this comes from a convention in accounting of writing losses or deficits in red ink in financial ledgers. The implication perhaps being that there is a collective carbon debt which need to be repaid in order to reach a point of greater sustainability. This is perhaps a tenuous association, but there is a sound logical connection between the concept of financial debt and the idea of a sort of carbon debt that needs to be managed in a sustainable way to avoid negative consequences, and this subconscious link be- tween the two in these visualisations may serve to supplement the broad thrust of the argument.
41 Colour in IPCC reports Considering the symbolic meanings often conferred onto the colour red and the supposed strong ergonomic response it can elicit, the IPCC visualisations make rel- atively sparse use of the colour and its potential. IPCC assessment reports have made some use of the colour red, with its cul- tural and symbolic meanings being employed in order to enhance the communica- tive power of the visualisation in question. Red and its strong psychological asso- ciations with heat has been utilised on a number of occasions when visualising a two-dimensional map of the globe. One particularly striking example can be seen below. Using different intensities of shade to illustrate which geographical areas of the Earth will experience the greatest degree of heating, this graphic communicates simply and implicitly the message it is designed to convey. Even without any extra labelling, the use of colour and scale in degrees Celsius underneath is all that is required to convey the message that the planet is both warming and certain areas are more likely to be impacted than others.
Fig. 19: [Original caption] “Projected surface temperature changes for the late 21st century (2090-2099). The map shows the multi-AOGCM average projection for the A1B SRES scenario. Temperatures are relative to the period 1980-1999.” Source: IPCC, 2007, Climate Change 2007: Synthesis Report, Cambridge University Press, Cambridge, p.9.
The significance of upward trending line graphs within IPCC report data vis- ualisations – and climate change visual discourse in general – will be analysed in some detail in a later section, at which point the following two figures may be worth referring back to. But for the purposes of this section, we are concerned specifically with the use of the colour red in these two objects. We can see in both examples that the red lines of the graphs are designed to cause alarm. In the case of the first example, it shows a relatively stable line trending sharply upwards, in what is known as a “Hockey Stick” shape. This graph argues for a global temperature which
42 is being observed to be warming at a rate which is concerning to scientists, and that the probable cause of this observation is human activities, or anthropogenic factors.
Fig. 20 (left): [Original caption] “Simulating the Earth’s temperature variations (°C) and com- paring the results to the measured changes can provide insight to the underlying causes of the ma- jor changes.” Source: IPCC, 2001, Climate Change 2001: Synthesis Report, Cambridge Univer- sity Press, Cambridge, p.7. Fig. 21 (right): [Original caption] ”Global average surface temperature change (a) and global mean sea level rise10 (b) from 2006 to 2100 as determined by multi-model simulations. All changes are relative to 1986–2005.” Source: IPCC, 2014: Climate Change 2014: Synthesis Re- port, IPCC, Geneva, p.11.
This finding is necessarily alarming; therefore, the authors of the report uti- lised a colour ergonomically proven to provoke a response, and which signifies danger and heating. Similarly, the second example, for its graph describing surface temperature change and sea level rise, opts to use both red and blue. The use of blue resonates with one of the subjects being represented: sea level rise. The use of red emphasises the warming in the surface temperature change graph. In both graphs, the most upwardly rising line is the red line, this is likely not by chance, but a con- scious effort to harness the alarming connotations of that particular colour. As we can see from the following visualisation from the fifth assessment re- port (2014), the authors decided to eschew the use of red altogether and to produce instead a visualisation of their data with an entirely different colour theme: green. The colour association here is interpretively straightforward. The colloquial, col- lective term for gases emitted into the atmosphere as a result of burning fossil fuels, among other human activities, which produce a warming effect on the Earth’s cli- mate, is greenhouse gases (GHG). Greenhouse gases include nitrous oxide, me- thane, and ozone; but the most common greenhouse gas is carbon dioxide (CO2). Here we have a dynamic line graph paired with two sets of boxplots, which tracks GHG emissions of the past and project those of the future, depending on different scenarios of collective human action based on commitments made by policymakers.
43
Fig. 22: [Original caption] “The implications of different 2030 greenhouse gas (GHG) emissions levels for the rate of carbon dioxide (CO2) emissions reductions and low-carbon energy upscaling in mitigation scenarios that are at least about as likely as not to keep warming throughout the 21st century below 2°C relative to pre-industrial levels (2100 CO2-equivalent concentrations of 430 to 530 ppm).” Source: IPCC, 2014: Climate Change 2014: Synthesis Report, IPCC, Geneva, p.23.
The use of colour in this figure signals with great clarity what the subject of the data visualisation is: Greenhouse Gases. Signalling to the reader the subject of the graphs before the reader reads them, but the use of colour does little else. It does nothing to progress the argument of the authors, nor does it clarify the argument itself. In other words, it does not make the graph easier to read. While this figure does not utilise the emotive power of the colour red, nor does the colour that is utilised – green – add much to the persuasiveness of the visualisation itself, but to merely signal its content. There is at least some meaningful connection to the use of colour and the purpose of the graphic. This is frequently not the case with data visualisations in IPCC reports. As we can see from the following examples, taken from a range of reports from 2001 to 2014, these visualisations constitute a more representative cross-sec- tion of the use of colours featured in the reports. The strict and strategic use of colour which has previously been discussed, and which will also be demonstrated by non-IPCC climate visualisations in the next section, is seemingly absent in these examples. Instead, different colours used to denote different warming scenarios, different levels of emissions, different segments of pie charts, different lines of line graphs, seem to be assigned in a way which is entirely arbitrary. Objects are col- oured in order to distinguish from each other for the purposes of clarity in that dis- tinction, rather than out of any motivation to persuade the reader-viewer. This use
44 of colours seems to show a certain lack of consideration for the communicative and persuasive potential of certain colours in a specific context. This absence of atten- tion to the usefulness of colour in climate data visualisation design is generally not a feature of those visualisations produced outside of the IPCC’s assessment reports, as the following section will show.
Fig. 23 (top left): [Original caption] “After CO2 emissions are reduced and atmospheric concen- trations stabilize, surface air temperature continues to rise slowly for a century or more.” Source: IPCC, 2001, Climate Change 2001: Synthesis Report, Cambridge University Press, Cambridge, p.17. Fig. 24 (top right): [Original caption] “(a) Global annual emissions of anthropogenic GHGs from 1970 to 2004.5 (b) Share of different anthropogenic GHGs in total emissions in 2004 in terms of CO2-eq. (c) Share of different sectors in total anthropogenic GHG emissions in 2004 in terms of CO2-eq. (Forestry includes deforestation.)”. Source: IPCC, 2007, Climate Change 2007: Synthe- sis Report, Cambridge University Press, Cambridge, p.36. Fig. 25 (bottom): [Original caption] “Global greenhouse gas emissions (gigatonne of CO2- equivalent per year, GtCO2-eq/yr) in baseline and mitigation scenarios for different long-term concentration levels (a) and associated upscaling requirements of low-carbon energy (% of pri- mary energy) for 2030, 2050 and 2100 compared to 2010 levels in mitigation scenarios (b).” Source: IPCC, 2014: Climate Change 2014: Synthesis Report, IPCC, Geneva, p.21.
45 Colour in non-IPCC climate visualisations A striking difference between the visualisations incorporated into IPCC as- sessment reports and climate change visualisations originating outside of this au- thority within the discourse, is the use of colour in the graphical choices when rep- resenting data, and particularly the use of the colour red. This section will discuss a select number of visualisations produced outside of the IPCC report making pro- cess, from both academia and journalism, which make frequent, deliberate, and pointed use of colour. These examples demonstrate some of the most pronounced uses of colour (and red in particular) within this visual culture, but this feature is a common trait in climate change visualisations as a discourse generally. The first example is an example of a scholarly data visualisation that was produced outside of the IPCC by Michael Mann and Raymond Bradley, but which was later co-opted into the third assessment report (2001). It became the focal point of that report and was even featured prominently at the press conference in which the report was released. The graph became known as the “Hockey Stick” and was the subject of much debate both within and without the climate science discourse, but this will be explored in detail in the following section. Pertinent to this section is the way in which colour is used in this original version of the Hockey Stick graph.
Fig. 26: Green dots show the 30-year average of the new PAGES 2k reconstruction. The red curve shows the global mean temperature, according HadCRUT4 data from 1850 onwards. In blue is the original hockey stick of Mann, Bradley and Hughes (1999 ) with its uncertainty range (light blue). Source: Wikimedia Commons.
The graph depicts a line that is relatively stable and flat, with points hover- ing around a regular temperature. This changes radically in the most recent one hundred years, shooting up multiple points on the y-axis. The stable portion of the graph is blue, with the line switching to red as it shoots up the chart in an exponen- tial manner. The difference in colour is ostensibly set to denote the difference be- tween proxy data and direct temperature recordings (the difference between these two data types will be elaborated on in the next section), but the emotive and
46 symbolic result of the colour choice is “we as humans used to be in the blue, now we’re in the red”. Again – in this visualisation – alarm, danger, and heat are the overriding psychological associations with the colour choices. The next example again illustrates the narrative of a warming planet, but in a slightly different way. This example, from a BBC News representation of NOAA (National Oceanic and Atmospheric Administration) data, charts average annual temperatures for the twentieth century and highlights the coldest and warmest years with blue and red lines, respectively. The graph emphasises that recent years have been warm far above the average for the century, in a century that is already warm- ing, but the use of colour improves the clarity of the message and the efficiency with which it is communicated.
Fig. 27: “How years compare with the 20th Century average”. Source: BBC.
Another example of climate data visualisation that comes from the world of journalism, rather than climate science, is Figure 28. This graph with its upward trending lines is an allusion to the Hockey Stick graph, but interestingly it segments what is being measured – CO2 emissions – by geographical region. Again, we see a colour palette that gradiates from dark to light blue, then light to dark red as we observe the rising CO2 emissions over time. In this example, there is something to be said for the decision to segment geographically in the way that has been done here. The segmentation seems to be somewhat arbitrary, not limiting itself to either nations or continents or general regions. The segments are perhaps divided into spheres of political influence but seem to give little thought for the sizes of popula- tion these segments represent. The placing of China into the top, most red part of the image is also perhaps somewhat problematic. By segmenting in this way and placing China in the reddest position, it could be argued that it may not be
47 unreasonable to suggest this graph taps into the cultural subconscious of the reader where red = bad and presents the carbon output of China as somehow more negative or more dangerous than European carbon output. These two versions of the same graph also demonstrate another problem of graphical representations of data, that is that one visualisation looks much more alarming than the other. The shortening of the x-axis steepens the incline and makes the graph look more dramatic than the version on the left.
Fig. 28: “The business of climate change”. A graph showing CO2 emissions from 1850 to 2017, segmented by region. Source: The Economist.
Finally, we come to an example of climate data visualisation that makes extremely efficient use of colour. In fact, it only uses two colours, various shades of red and blue. And that is all the image uses. Warming Lines by Ed Hawkins uses no text or numbers, no markers of any kind, instead it just makes use of block col- ours in vertical straight lines. To essentially render the “Hockey Stick” graph into a different visual form that relies entirely on colour. Works like Warming Lines can be said to be more on the Avant Garde of climate data visualisation, rather than adhering strictly to the conventions of data visualisation of the natural sciences. Here, Hawkins makes excellent use of colour. Utilising a very simple form with uniform vertical lines, Hawkins communicates an argument very clearly: global temperatures were once consistently cool, but recently this has changed, and now the Earth is becoming increasingly warm. The use of colour indicates a relative coolness transitioning quite suddenly to a relative hotness, it communicates a sud- den shift from good to bad, and a sudden shift from security or neutrality to danger.
48 Fig. 29: An early warming stripes graphic published by their originator, climatologist Ed Haw- kins.[1] The progression from blue (cooler) to red (warmer) stripes portrays the long-term in- crease of average global temperature from 1850 (left side of graphic) to 2018 (right side of graphic). Source: Wikimedia Commons.
Recurring Forms: The “Hockey Stick” Graph & Upward Exponentials
Quite possibly the most consequential recurring visual form in the visual culture of the IPCC reports is what has come to be known colloquially in climate data visual- isations (and other line graph examples in a variety of settings) as the “Hockey Stick” graph. It has recurred many times for a variety of empirical representations, but it is most commonly used to represent either global or hemispheric temperature records for periods between 500 and 2,000 years. Because of the large temporal scope, these records are often formed by a process of reconstruction, rather than direct observation, due to the timescales involved and the only very recent practice of temperature recording in a systematic, scientific manner. The data behind this visual form has only become more comprehensive as time has gone on. The earliest form of this graph was produced using data collected from the northern hemisphere exclusively and operated within a timeframe of around 1,000 years; later versions utilised more geographically comprehensive samples to produce a global model which covered a span of 1,400 years. Even with this broader data view, the graph produced still exhibits the unmistakable “hockey stick” shape (Mann 2014, p.261).
49 The “Hockey Stick” emerged into public consciousness to great fanfare, as well as intense debate, and over the course of almost a quarter of a century has cemented itself as one of the cornerstones of climate change visual discourse. The image has not been free of controversy, however, ‘[f]or politicians, pundits, and interest groups sceptical of the evidence for greenhouse warming, the hockey stick has become a potent symbol’ (Monastersky 2006, p.10). Emerging as a boundary object for both sides of the debate, it has been used in the efforts to construct a meaningful narrative for those seeking to raise the alarm about anthropogenic cli- mate change and for those seeking to bolster a sceptical argument against the sci- entific consensus.
Fig. 30: Sir John Houghton, co-chairman of Intergovernmental Panel on Climate Change (IPCC), explains a diagram of global temperature Monday, Jan. 22, 2001, at a news conference. Source: The Weather Channel.
The “Hockey Stick” graph was first produced by the climatologists Michael Mann, Raymond Bradley and Malcolm Hughes (Mann, Bradley & Hughes 1999, p.12) before being incorporated and featured prominently in the pages of the 2001 IPCC report, later taking on a life of its own in the wider public discourse on climate change. It appeared notably and prominently at a televised press conference, hosted by the IPCC and unveiling the organisation’s latest report. The graph can be seen in Figure 30 behind one of the report’s lead authors and the IPCC’s then-chairman, Sir John T. Houghton. The graph was displayed behind Houghton for the entire event. The prominence of the graph’s presence at the event was likely due to the visual persuasiveness of the form, but the emphasis on this particular aspect of the report above all else would become a point of contention and criticism.
50 The persuasive visuality of the graph lies in the exponential rise in tempera- ture on the right-hand side of the graph. For reference, Figure 31 shows a simplified graph demonstrating an exponential function. Graphs that feature an exponential form are common in both the natural and social sciences, including climate science. Exponential graphs show data that has been transformed by the irrational constant e, where e = 2.718. This function results in what in economic terms is referred to as exponential growth; which, mathematically speaking, when the rate of increase of the function at x is equal to the value of the function at x. In layman’s terms, this function results in what we see here, a line that is trending upwards with an increas- ingly steep gradient, signifying a compounding effect on the phenomenon being measured.
Fig. 31: The natural exponential function y = ex. Source: Wikimedia Commons.
The initial research that originally produced the “Hockey Stick” graph and numerous subsequent, similar investigations rely on the use of so-called proxy data. The use of proxy data forms one of the main criticisms of this graph, its authors, and the underlying research; so, it is important to explain what proxy data is and what it means in this context. Proxy data is data that does not measure a phenome- non directly, but instead it is unrelated data that can be analysed to give an indica- tion of the phenomenon a researcher wants to investigate to within a certain margin of error. According to the National Oceanic and Atmospheric Administration, ‘[p]roxy climate indicators include oxygen isotopes, methane concentrations, dust content, as well as many other parameters’ (NOAA 2021). Richard Monastersky (2006, p.11) contextualises the use of proxy data in the specific case of the “Hockey Stick” graph when he recounts that
‘[s]ince reliable thermometer records reach back only a little more than a century in most places around the globe, researchers like Mr. [Michael] Mann, who are interested in earlier times, have to look for clues in other places. They often consult natural recorders of cli- mate information, like tree rings, sediments at the bottoms of lakes, and the annual ice layers in glaciers. Each of those phenomena grows one year at a time, locking in infor- mation about annual snowfall, temperature, wind speeds, and other indications of past conditions.’
51 Therefore, we can see that – in the absence of first-hand data and the impossibility of ever obtaining first-hand data directly – proxy data is a flawed but essential sub- stitute, and the only means of understanding global temperature variations over such long periods of time. A common theme in climate science visual culture is the practice of reduction. There is disagreement over the extent to which data visualisation as a practice should be regarded as the presentation or representation of the phenomena it is at- tempting to capture. But what must be acknowledged in climate science is that the special and temporal compression involved in displaying features of a planet’s cli- mate in a two-dimensional image that can fit onto the page of a scientific report is an act of significant reduction. There is some question over whether this process is capable of producing any object of intellectual or scholarly value (Elkins 2008, p.191). This is the immense challenge of the IPCC’s climate science reports – and for data visualisation in general – ‘no matter the field, [the medium] was always a small window through which one could read a very few signs from a rather poor repertoire (diagrams, blots, bands, columns)’ (Latour 1986, p.4). In the case of the “Hockey Stick” the image is reduced further still: a mass of points and lines that dip and spike and move on the page surrounded by wide margins for error are re- duced to two component parts: A “shaft” and a “blade”. The shaft represents a long period of relatively minor temperature variations before transitioning into the blade, which illustrates a sharp mercury upswing during the last century or so. In scholarship there is often a tension between the privileging of detail versus overview, and striking a balance between these two opposing impulses is often a subjective judgement, the aim of which is to strike upon the “best” way of com- municating a particular set of ideas. An overemphasis on detail can serve to obscure a wider context, while prioritising overview can result in the overlooking of certain details. The reduction of a century of temperature recordings and centuries more of proxy data designed to give an indication of the average annual temperatures of a hemisphere or even an entire planet into a line graph shaped like a hockey stick is bound to result in disagreements over the degree of reduction. If not the graph itself, certainly the discourse around it has gravitated towards the overview end of the detail-overview spectrum, but the result is an argument rendered into a two-dimen- sional data visualisation that is as clear as it can possibly be. When the problem it seeks to address is so urgent, and when the underlying data has been verified and reproduced many times over, the simple form of the “Hockey Stick” is difficult to criticise as “oversimplified”. Having made an impact not just within the climate science discourse, the graph has become an object of interest in popular culture, in politics, and in busi- ness. As a result, the “Hockey Stick” is ‘one of the most scrutinized scientific graphs in recent memory’ (Monastersky 2006, p.10). Perhaps to the detriment of other sources of evidence of a changing climate and warming planet, this graph has
52 become a focal point in the debate over anthropogenic climate change. With some parties – particularly those who are sceptical of the existence of climate change, or at least the human role in it – attempting to centre the entire debate on the merits or flaws in this particular graph, in the hopes that to discredit this visualisation would mean to discredit the entire argument. The Wall Street Journal, in a less than complimentary editorial that curiously carries no by-line from July 2006, admitted to the ubiquity of the form, stating that the graph ‘has cropped up all over the place’ (WSJ 2006). The “Hockey Stick” graph originates with Michael Mann and his collaborators in their pioneering hem- ispheric temperature findings from proxy data. It then appeared in the 2001 IPCC Assessment Report (although line graphs of a similar shape had appeared before and since in other IPCC reports) as well as in more esoteric cultural locations, such as Al Gore’s 2006 documentary film An Inconvenient Truth and the blog of a Ca- nadian retired mining consultant dedicated to the graphs discreditation (cli- mateaudit.org), and finally – most likely – every major newspaper in the world. The Wall Street Journal editorial also went on to claim that the graph was ‘a man-made global warming evangelist’s dream’, but the image also seems to have served as a significant rallying point for climate sceptics too. In fact, it might be argued that the “Hockey Stick” graph is something of a boundary object in climate change visual discourse, a standardised form (Star & Griesemer 1989, p.394) whose “plasticity” means it is interpreted differently by different groups (ibid). Regarded differently by different factions or communities within the discourse (Monastersky 2006, p.13), those who regard climate change as anthropogenic, as cause for alarm and urgent social and political action, view it as one of the most crucial and convincing, as well as one of the most alarming, pieces of evidence so far produced by climate science researchers. While another community of climate change sceptics or deni- ers see it as one of the most misleading artifacts in circulation within the discourse, and express displeasure with the way in which this graph has been granted ubiquity and authority in the climate debate. This is despite its reliance on proxy data and the associated uncertainty that comes with attempting to discern historical temper- atures from such sources. The visual form of the “Hockey Stick” was seized upon almost immediately as a potent symbol in the argument over anthropogenic climate change. ‘In the wake of the [2001] IPCC report, the paparazzi of the climate-change debate swarmed around the suddenly famous hockey stick’ (Monastersky 2006, p.13). Intense inter- est in the image came from all sides of the debate, with both camps applying some degree of distortion or overemphasis. The reality was and still is that the graph rep- resents very credible findings that have been replicated on several occasions, but that from the first instance of this graph even its authors have treated it with caution. But instead – spurning a nuanced view – ‘[e]nvironmental groups and some gov- ernment reports pictured the curve in an overly flattering light, while sceptics of
53 greenhouse warming showed it in the harshest glare possible, distorting its features for their own purposes’ (Monastersky 2006, p.13). As Weart (2021) explains,
‘the “hockey stick” graph was prominently featured in a report the IPCC issued in 2001. The image immediately became a powerful tool for people who were trying to raise public awareness of global warming — to the regret of some seasoned climate experts who rec- ognized that, like all science at the point of publication, the graph was preliminary and uncertain. The dedicated minority who denied that there was any global warming problem promptly attacked the calculations.’
As we can see, the “Hockey Stick” has a complicated legacy. A prominently fea- tured visual form in climate change discourse, its clear message and persuasive powers means that it has been a useful tool for scientific communication and spread- ing awareness of a perilous environmental issue. However, some climate scientists and activists may consider the over exposure of the graph as having resulted in a distracting and unnecessary sideshow, that gifted climate sceptics a talking-point to hang their arguments on in order to conceal their bad faith, and may have resulted in the neglect of other potent and persuasive visual forms.
Fig. 32: [Original caption] “Forty year smoothed reconstructed late-summer Arctic sea ice extent with 95% confidence interval.” Source: Kinnard et al. 2011.
It is interesting that one of the lead authors and architects of this visual form’s ubiquity in climate science debate views it as a storytelling device. The “Hockey Stick” graph is a ‘central figure in the debate over human-caused climate change. It tells a simple story: Earth’s temperature underwent only modest variations in much of the past millennium until spiking abruptly upward with the advent of in- dustrialization and fossil fuel burning’ (Mann 2014, p259). Illustrating the central- ity of this form to the communication of climate science is the emergence of an inverted version where the hockey stick arcs downward to illustrate the reduction in sea ice in the Arctic (Kinnard 2011, p.511).
54 According to one of the graph’s lead architects and one of its staunchest de- fenders, there now exists a veritable “Hockey League” that has emerged from the number of times the same questions have been asked, the same data replicated, and the same conclusions reached – with the same graph shape (Mann, TedTalk, ~6:38). The existence of a recurring form is important in this context because science is predicated on the concept of repeatability and replicability. It is for that reason that the emergence out of a large number of studies from unrelated institutions, organi- sations, or individuals which result in an almost identical visual form is of great interest, importance, and signals the veracity of the image. Figure 33 shows a version of Mann’s “Hockey League”. An aggregated im- age of various studies that have attempted to “reconstruct” deep historical temper- atures. We see the familiar “Hockey Stick” form. Labelled on the graph are the two periods referred to as the “Medieval Warm Period” and the “Little Ice Age”. As we can see from the assembled studies, neither of these periods represent adequate di- gressions from the mean to enable a recontextualisation of our current warm period as part of a previous, natural trend in temperature fluctuations. The current rise in temperatures is sharp and continues to rise, and – within these visual forms at least – not possible to recontextualise as anything other than unusual.
Fig. 33: [Source caption] “This image is a comparison of 10 different published reconstructions of mean temperature changes during the 2nd millennium. More recent reconstructions are plotted towards the front and in redder colors, older reconstructions appear towards the back and in bluer colors. An instrumental history of temperature is also shown in black. The medieval warm period and little ice age are labeled at roughly the times when they are historically believed to oc- cur, though it is still disputed whether these were truly global or only regional events. The single, unsmoothed annual value for 2004 is also shown for comparison”. Source: Wikimedia Commons.
A new, longer upward curve in recent studies has even led some commenta- tors to alter the nomenclature, opting to refer to the graph shape as “the scythe”
55 rather than “the hockey stick” (Mann 2014, p.261). This shift in the language sur- rounding the graphical form is an interesting development and illustrates a curious relationship between written and visual imagery in climate science. These two ob- jects: the scythe and the hockey stick are similar in shape and both are applicable terms for the shape of these particular graphs, but the difference in symbolism is stark. A hockey stick is leisurely, non-serious, even juvenile. A scythe is morbid, serious in the extreme, and obviously designed to conjure up images of death in a way that, say, a hockey stick does not. This graphical form is of interest and likely features so prominently in climate science published research and IPCC reports because of its compositionally persua- sive characteristics. The stability and continuity indicated by a generally flat – even downward trending – line for hundred-year periods, followed by a sharp upward trending line communicates a clear and simple message. The message it communi- cates is that there has been a recent and dramatic change to the status quo of the Earth’s climate. This message suits the purpose of the IPCC as it attempts to form a discourse around the notion of anthropogenic climate change. Which explains why it is featured so extensively in IPCC reports and climate science research liter- ature at the expense of other visual forms, which are featured less prominently and offer a less striking visual composition. It is for this reason that this visual form is featured so prominently in activist literature and has been featured, remixed, or al- luded to in a wide variety of forums and media.
Fig. 34: [Original caption] “The 2nd of my 4 horsemen of the 2018 apocalypse: climate change.” Source: Mona Chalabi/Twitter.
56 The prominence of a graph trending upwards to the right, signifying an often sharp increase, has become a powerful trope in the scopic regime of climate change. Meaning has been constructed around this form and its visuality to the extent that its meaning is immediately obvious to the viewer, and for this reason the form has been co-opted and woven intertextually into the fabric of climate change discourse. We can see in Figure 34 how this trope has been used to great effect by the data journalist Mona Chalabi. Disposing entirely with the received visual style of the natural sciences, which seeks to project a sense of objectivity or neutrality, Chalabi (Twitter, 2018) telegraphs her argument and makes to no pretence to objectivity or impartiality. The argument she is making is clear from the artistic flair of the data visualisation, but the argument is also immediately clear because of her utilisation of this familiar graph shape. The form’s visual persuasiveness, the ability it has to communicate its mes- sage clearly and simply – the argument that the graph is making can be discerned almost at a glance – is also a reason why anthropogenic climate change sceptics have also seized upon this image and those produced by other researchers that ex- hibit a similar visual form (this “Hockey Stick” shape) and waged a campaign to discredit the underlying data. The use of proxy data and the potential margins for error have been well advertised by the producers of these graphs from their incep- tion (Mann, Bradley & Hughes 1999, p.6). However, the acknowledged wide range of potential error has nonetheless been homed in on by some scholars and politi- cians, particularly in the US (Monastersky 2006, p.10), who would like to downplay the extent to which the planet is warming, or indeed point to periods in the past when temperatures were warmer for a time; such as the so-called “Medieval Warm Period” (approx. 900-1300 CE). Climate change sceptics also point to a period known colloquially as the “Little Ice Age” which lasted from around 1500-1800 CE which they argue was a period that had a colder climate than our current period, which contextualises recent warming observations as a reversion to the mean, rather than an upward spike. One might be tempted to argue that neither of these two arguments can hold water at the same time. Either the data has margins for error too wide to infer any- thing definitive from them, or they demonstrate a “Medieval Warm Period” and a “Little Ice Age” that contextualise our current warm period as not unusual or ex- ceptional: but it cannot work both ways. The intricacies of the data, the way it was assembled and the underlying statistical principles that relate to concepts like mar- gins for error are not the focus of this thesis, nor is it within the realm of this re- searcher’s sphere of expertise. But speaking compositionally on the form and shape of the graph, the “Medieval Warm Period” and “Little Ice Age” arguments seem somewhat spurious, since neither of these periods on the graph approach the levels of temperature increase – or decrease in the case of the Little Ice Age – that has been observed during our current period.
57 On the other side of the debate, climate change activists and – as outlined in the introduction – the majority of climate scientists view the “Hockey Stick” visual form as a potent symbol, and a linchpin of climate change iconography. Variations on an upward trending line graph, often depicting something like an exponential increase as the line approaches the extreme right of the x-axis, are frequently em- ployed iconographic images employed particularly by climate change activists or advocates who are not necessarily affiliated with a research institution, but are in- stead journalists or charities.
Fig. 35: A line graph laid over Ed Hawkins’ “Warming Lines”. Source: Wikimedia Commons.
Figure 35 shows a composite image of the two major objects of study in this thesis: a climate science data visualisation that both displays a “Hockey Stick” graph and makes effective use of colour in communicating the problem of anthro- pogenic global warming. In this sense, Warming Lines by Ed Hawkins in the most quintessential visual object in climate discourse, because it communicates the dis- course’s most persuasive compositional form in an aesthetically efficient way that harnesses the cultural and psychological power of colour. A seamless marriage of the two dominant recurring forms in climate change’s visual culture.
58 Discussion and Conclusions
The previous sections online the problem on scientific miscommunication on the issue of climate change. There is a strong scientific consensus on the issue, but public and political discourse and opinion polling suggests that beyond the world of climate research there is a greater sense of scepticism. This thesis so far has set out to engage with the visual culture of one of the central institutions in this dis- course – the IPCC – and sought to better understand this visual discourse through descriptions of the variations and development of the culture and through intertex- tual comparisons between IPCC data visualisations and the wider discourse of cli- mate visualisations. Using a humanistic methodology of discourse analysis and employing theo- retical assumptions about the centrality of visual images in scientific communica- tion. This thesis has analysed how the IPCC engages in a process of meaning con- struction by utilising iconographical and socio-culturally significant objects such as the now famous “Hockey Stick” graph and extensive use of the colour red. How- ever, this compelling use of imagery is relatively rare in the full scope of the IPCC’s reporting. While the reports’ authors do often make good use of familiar forms of graphical representation of data that are accessible to the public, they often do not go far enough in engaging with more creative and artistic methods to produce per- suasive objects. Instead, the underlying argument of the graph is obscured by a con- formity of the visualisation to an aesthetic standard of minimalism that is common in the natural sciences and is designed to convey a sense of impartiality and objec- tivity, but this often serves to make the graph more difficult to comprehend. In the process of dispensing with this minimalist aesthetic while utilising fa- miliar graphical forms and effective use of colour, the IPCC could progress in a more positive direction in its efforts to effectively communicate the problem of an- thropogenic climate change. Despite this it may be argued that this is not necessarily the role of the IPCC, and that the institution’s power instead lies in its ability to set a visual agenda in the climate change discourse that is employed and reimagined more persuasively in more widely circulated literatures in the realms of journalism and activism. This will be discussed in the conclusions. The final discussion of this thesis will be centred on the question of what makes for good data visualisation. This general discussion will be continuously related back to the specific findings of the empirical section. This section will cover discussion points including: some general background discussion of what makes for “good” data visualisation, with particular refence to the central works on this topic from Tufte (1983) and Healy (2019); a discussion on how these principles might be em- ployed or disregarded by the IPCC in relation to the area of information aesthetics; the accepted aesthetic standards of scientific data visualisations – particularly in the
59 natural sciences – and whether these are too narrow and dismissive of artistic ex- pression so as to limit their communicative potential. In light of these topics, I will also discuss the tension between a minimalist “data-to-ink” ratio and creative ex- pression in producing memorable visualisations and the folly of the pursuit of “ac- curate” data representations. This section will also consider why a humanist-critical perspective is important when discussing what is “good” data visualisation; the ten- sion between data visualisation as a means of making an argument vs. data visuali- sation as a means of making meaning; discussion around visualisations as presen- tations or representations of data, perceived and real; data visualisations as immu- table mobiles; and ideas around familiar forms with surprising visuality being the most effective visual communicators. In the course of this thesis a number of data visualisations have been considered and analysed, and the overarching lesson that has been learned (which may seem obvious, but it is an important starting point for the discussion) is that ‘[s]ome data visualizations are better than others’ (Healy 2019, p.1). This is such a simple state- ment, but it is important to begin by recognising that data is not merely visualised and that is all. The presentation of numbers or statistics in a visual medium, a straightforward relationship without interference or interpretation. This is not the case. In visualising data, data scientists and designers are making a large number of discrete decisions and engaging in a process of meaning construction that affects the final visualisation that is produced, and this subjective process is open to scru- tiny with regard to whether the visualisation is “good” or “bad”. In the context of the IPCC assessment reports, a “good” visualisation is one whose visuality contrib- utes to a narrative of a changing climate driven by human factors, one that com- municates this effectively and efficiently using persuasive visual tropes such as a rising line graph or prominent use of the colour red. These considerations for what make for “good” data visualisation are often not recognised. Instead, particularly in the natural sciences, emphasis is often placed on visual styles that reinforce an idea of objectivity in the viewer, rather than consid- ering the potential for a visualisation to sit within a scopic regime that would per- suade the viewer to subscribe to a particular argument, or be able to ascribe a par- ticular meaning to the visual object. This realisation adds another complicating fac- tor to the already challenging task of making “good” data visualisations. The idea that producing the best data visualisation possible is not a simple as inputting the data into a computer program and receiving at the other end a perfect and object presentation of the phenomenon you are attempting to observe is not new. Practi- tioners when discussing the challenge of good data visualisation admit that while ‘it is tempting to simply start laying down the law about what works and what doesn’t, the process of making a really good or really useful graph cannot be boiled down to a list of simple rules to be followed without exception in all circumstances’ (Healy 2019, p.1). This assertion by Healy is a sensible one, but this thesis seeks to
60 identify a particular context, or a particular set of circumstances – scientific com- munication on climate change from the IPCC – and, as we can see from the analysis, it is possible to identify certain visual tropes that can be employed effectively and consistently to construct meaning around the science being presented. That the changing climate is driven by human factors, and that radical action is needed to mitigate against the consequences. The visualisations of the IPCC reports are interesting to consider in light of the relationship between concepts of looking, seeing, and knowing; how these concepts had previously been conflated and how that paradigm has shifted in the postmodern era to produce a break from the previous held notion of looking and seeing being equivalent to knowing (Jenks 1995, p.3). Instead of being a means to knowing, it is perhaps more accurate to think of IPCC data visualisations as more in line with what Bradley (2019, p.14) referred to as tools for exploring, seeing, and thinking. Visualisations have the capacity to facilitate knowing, but the straightforward con- nection between looking and knowing has been broken in our postmodern sensibil- ities. This is not to say that data visualisations have no value, on the contrary, they ‘offer extremely valuable tools that we should use in the process of exploring, un- derstanding, and explaining data’ (Healy 2019, p.2). But in this “process” there is a degree of interpretation and meaning construction that is going on which often goes unacknowledged and raises questions about the value of insisting upon an “objec- tive” seeming aesthetic when there is always an element of argumentation at play. This tendency among hard science disciplines to frame data visualisations as objective presentations of reality by producing visual objects that possess a mini- malist aesthetic is somewhat misplaced, and instead of having the effect of project- ing a sense of accuracy or objectivity, instead organisations like the IPCC are miss- ing the opportunity to make a stronger argument for their cause by weaving that argument into the visuality of the data visualisation objects they produce. Great emphasis is placed on the visual objects science produces, as discussed in the theory section, this has been a historical trend, and this thesis argues that the IPCC’s im- ages should be privileged over its text because of the greater accessibility to the audience and the increased mobility of the images themselves that can be reworked or remixed into more accessible contexts. But that is not to say that these are perfect objects through which the audience sees the problem of climate change, ‘they are not a magical means of seeing the world as it really is. They will not stop you from trying to fool other people if that is what you want to do, and they may not stop you from fooling yourself either’ (Healy 2019, p.2). They are instead a means to make an argument, an argument which visually the IPCC often does not make strongly enough. It is difficult to discuss the most prominent ideas around good data visualisation practice without touching upon Edward Tufte’s writing on the subject. Outlining the most common position on best practices for data visualisation, he writes that
61 ‘[g]raphical excellence is the well-designed presentation of interesting data—a matter of substance, of statistics, and of design. ... [It] consists of complex ideas communicated with clarity, precision, and efficiency. ... [It] is that which gives to the viewer the greatest number of ideas in the shortest time with the least ink in the smallest space. ... [It] is nearly always multivariate. ... And graphical excellence requires telling the truth about the data.’ (Tufte 1983, p.51) Tufte has been incredibly influential in this arena and his dictums have become gospel for many data visualisation practitioners, but it might be said that his view of what makes for good data visualisation is too simplistic. His positivist view of truth, data, and the possibility of visualisation to convey these two things shows a somewhat naïve view of the world, and certainly in the case of climate science – as is shown in the controversy over the “Hockey Stick” graph – the possibility of cap- turing some pure truth about the state of the climate which is not open to interpre- tation or debate is fanciful. Tufte himself even acknowledges that often the most exciting and effective data visualisations disregard his own rule of thumb recom- mendations. An example of a unique visualisation of information that is perfectly tailored to the purpose it was designed to fulfil, but is difficult to replicate, is Charles Minard’s graphic for Napoleon’s campaign in Russia. Minard’s design ‘can be described and admired, but there are no compositional principles on how to create that one won- derful graphic in a million’ (Tufte 1983, p.51). In lieu of design principles that can produce ideal, unique, and memorable graphics each time, authorities on visualisa- tion design have resorted to general rules of thumb, such as ‘encouragement to max- imize the “data-to-ink” ratio. This is practical advice’ (Healy 2019, p.7), but not a recipe for communicating true meaning and certainly not adequate advice for such an urgent problem as climate change.
Fig. 36: Charles Minard's 1869 chart showing the number of men in Napoleon’s 1812 Russian campaign army, their movements, as well as the temperature they encountered on the return path. Lithograph, 62 × 30 cm. Source: Wikimedia Commons.
62 Among the natural sciences – and data visualisation practice in general – there is a sense that to produce work that approaches something like what Mona Chalabi (as referenced in the analysis) produces would be in some way crass or counter to the received wisdom of what makes for data visualisation best practice. But in prac- tice a minimalist aesthetic to project an air of objectivity – which is often cited as a means to greater readability – often does precisely the opposite. Work such as Chal- abi’s or Charles Minard’s ‘are often more easily recalled than their plainer alterna- tives’ (Healy 2019, p.8), and do a greater service to the data which they are attempt- ing to represent. Furthermore ‘it may be the case that graphics that really do max- imize the data-to-ink ratio are harder to interpret than those that are a little more relaxed about it’ (ibid, p.8). A major concern for data visualisation designers is an eagerness to avoid so-called “chart junk”, the inclusion of unnecessary visual ele- ments in a chart that distracts from the meaning the designer is attempting to con- struct. But the clarity of the message a graph is attempting to convey can also be undercut by a lack of considered visuality, as well as an abundance of ill-considered visual elements. We can see from the visualisations of the first two IPCC assess- ment reports (1990 and 1994), but especially in the case of the first report, how a lack of visuality serves to make a message more difficult to discern, rather than easier. For this reason, it has been a positive change for IPCC report authors to increasingly embrace colour as a means to more effectively communicate their mes- sage and construct meaning. This need for greater consideration of visuality and design creativity signifies the need for a shift in the relationship between the “softer” subjects such as the humanities and the “harder” sciences. Greater humanistic consideration in natural science work would form part of an existing computational turn, and while previ- ously ‘the traffic in this computational turn has been predominantly one-way’ (Hall 2013, p.782) now is perhaps the time for the natural sciences to consider humanistic perspectives in their work. A breaking down of the boundaries between different research disciplines and different schools within the academy forms part of a Digital Humanities perspec- tive. The Digital Humanities Manifesto 2.0 outlines a radical vision for the disso- lution or deconstruction of traditional academic structures to allow for a move free- flowing relationship between disciplines. Built into this radical vision is also the idea that current imbalances in power and prestige (particularly between the hu- manities and the natural sciences) should be redressed, with each discipline re- garded on equal footing. They argue that fields such as computer science not only have the capacity to enhance the work of humanists, but that humanists can enhance the work of scientists. ‘Just as interesting as what computer science has to offer the humanities, however, is the question of what the humanities […] have to offer com- puter science. Beyond that, what can the humanities themselves bring to the under- standing of computing and the shaping of the digital?’ (Hall 2013, p.782). Certainly,
63 in the case of the IPCC report visualisations, what the humanities can bring is a keen appreciation of aesthetic factors, a historical view of design elements, and a sense of visual meaning-making that can assist data scientists in making the most effective and efficient visualisations possible. Instead the movement of ideas has often travelled in the opposite direction, ‘[t]he digital humanities have adopted conventions of information visualization and user interface that come from disciplines whose epistemological premises are fun- damentally at odds with humanistic methods’ (Drucker 2016, p.238) and while this has been a productive relationship to some extent there is a need to ‘engage in a critical description of visualization and interface from a humanistic-critical perspec- tive’ (ibid, p.238), not just for the benefit of humanities scholars – as Drucker is suggesting – but also to the benefit of other disciplines. Drucker argues that human- ists in particular are suited to this role, she writes that ‘[u]nderstanding the rhetorical force of graphical formats is a critical task to which humanities scholars are aptly suited by their training in close reading, though the language of visual modes of meaning production is still a foreign tongue for many’ (Drucker 2016, p.238), and it is these practices that this thesis has attempted to employ. This topic of discussion, which has circulated in the digital humanities space for some time, forms the main thrust of this thesis’ argument: scientific organisations like the IPCC should form more productive relationships with humanities practitioners in order to better pro- duce a productive and persuasive discourse on the problem of climate change through a more coherent visual identity. This thesis recommends that greater em- phasis is placed on a persuasive data visual language with familiar, historically and culturally rooted visual themes in order to better communicate the issue. The analysis of the IPCC’s visual culture has made clear that applying more humanistic-critical theory to the practice would serve to alter an ‘information visu- alization [culture that] predominantly focuses on effectiveness and functional con- siderations’ which ‘may be neglecting the potentially positive influence of aesthet- ics on task-oriented measures’ (Lau & Vande Moere 2007, p.1). Though a number of effective visual tropes are highlighted in the IPCC’s visual culture in this thesis, it is clear through intertextual comparisons with other climate change data visuali- sations that greater attention could be paid to the “influence of aesthetics” so that the organisation could make a more compelling argument. To this end, the IPCC and other natural science institutions would be well served to engage in a greater dialogue with information scientists, and particularly the field of information aesthetics. The analysis demonstrates a certain lack of aes- thetic consideration and consistency, with patterns or trends forming usually by chance. It should be argued ‘that information aesthetics bridges this apparent gap between functional and artistic intent by focusing on aesthetics as an independent medium that augments information value and task functionality’ (Lau & Vande Moere 2007, p.1). Information aesthetics balances the importance of good
64 mathematic practice with considerations for design and aesthetics that may serve to enhance the IPCC’s data visualisations, to add visual elements in order to make the information more rather than less clear. It is important to address this crisis of communication in climate science by abandoning this misguided idea that data visualisations should look minimal and objective. It is clear that to produce a visual culture that communicates more effec- tively there is a need for ‘more interpretive mapping techniques to augment infor- mation visualization with extrinsic meaning, or consider functional aspects in vis- ualization art to more effectively convey meanings underlying datasets’ (Lau & Vande Moere 2007, p.6). However, it is important that humanists or design professionals are not simply consulted on aesthetic matters, it is crucial that anyone who is incorporated into the report compilation process has an understanding of the underlying research and data. Schäfer and van Es (2017, p.17) acknowledge that ‘data analysis unfolds via computer interfaces that display results that users often mistakenly regard as objec- tive assessments.’ They go on to stress the importance of understanding the under- lying data that produces data visualisations, stressing a need for ‘knowledge work- ers who can grasp the processes of knowledge generation, from data collection through the various stages of analysis to visualization. These experts should be po- sitioned to question the data sets as well as the mathematical models which deter- mine the analysis’ (ibid, p.18). It might be argued that such intense scrutiny on these visualisations is not war- ranted, that they are just images designed to help explain or represent the scientific reporting on a particular problem. That they are of no great importance. But this thesis argues the opposite, that these visualisations are incredibly important, per- haps the most important aspect of climate science communication. For reasons that are most compellingly expressed by Bruno Latour, who wrote:
‘Papers and signs are incredibly weak and fragile. This is why explaining anything with them seemed so ludicrous at first. La Pérouse’s map is not the Pacific, anymore than Watt’s drawings and patents are the engines, or the bankers’ exchange rates are the econ- omies, or the theorems of topology are “the real world”. This is precisely the paradox. By working on papers alone, on fragile inscriptions which are immensely less than the things from which they are extracted, it is still possible to dominate all things, and all people. What is insignificant for all other cultures becomes the most significant, the only signifi- cant aspect of reality. The weakest, by manipulating inscriptions of all sorts obsessively and exclusively, become the strongest. This is the view of power we get at by following this theme of visualization and cognition in all its consequences’ (Latour 1986) (emphasis added).
These visualisations are not the Earth’s climate, or global temperatures past, present and future, they are mere representations of these things. But in these “fragile in- scriptions” exists a power to communicate. A power to argue and persuade. Ap- pearing in the assessment reports of the IPCC, these visualisations have the power
65 to “dominate” the discourse around climate change and the climate crisis. It is for this reason that they are worth paying attention to. A useful means of conceptualising the importance, if not the centrality, of these visualisations – particularly those visualisations of the later assessment reports – is through Latour’s concept of “immutable mobiles”. This is how this thesis would posit to describe these objects in highlighting their characteristics as the most ac- cessible and readable face of climate science communication and their ease of mo- bility/transferability, not only as digital image files but as objects that can be re- worked, remixed, and reinterpreted in other areas of the discourse. Latour described his idea of immutable mobiles when he wrote that ‘you have to invent objects which have the properties of being mobile but also immutable, presentable, readable and combinable with one another’ (Latour 1986, p.7) (emphasis in original). Images, particularly digital images, are unique in their mobility. They are easily transferable and transition into different contexts with greater ease than text, audio, or film. This mobility taken in addition to the immutability of the objects, by which I mean the ease with which images such as these can be understood, with their familiar forms and visually persuasive forms, results in a powerful object within the discourse which should be scrutinised intently.
Conclusions
This thesis has qualitatively analysed the visual culture of the IPCC’s assessment report data visualisations in an attempt to understand the discrepancy between the scientific consensus on the issue of climate change and why this has been met with such scepticism by the wider public. Using discourse analysis as a humanities- rooted methodology this paper has tracked the development and variations of IPCC data visualisations and delved deeply into the significance of the use of the colour red in climate change visual culture and on the significance of the “Hockey Stick” graph to this visual discourse. There is a degree to which the visualisations of the IPCC reports are not as effective as communicating their message as they could be, but the situation is not as dire as some of the previous literature would suggest. While the organisation restricts itself in its wider persuasive potential by sticking rigidly to a minimalist “data-to-ink” ratio that is the accepted practice of data visu- alisations within the natural sciences, this method of projecting accuracy, objectiv- ity, and clarity can often serve to undermine the clarity of the message rather than enhancing it. This is something the organisation should consider changing. Despite this, the IPCC’s institutional authority means that it has the power to influence wider climate discourse, and often serves to provide information for other organi- sations or individuals to synthesise into better examples of climate science commu- nication. Therefore, this thesis concludes by arguing that the IPCC does have some iconographic potential, as demonstrated by the “Hockey Stick” graph; but that more
66 artistic input would be welcome in future reports, which may do well – for example – to make better use of the colour red. There is some indication that this is the direction the organisation intends to move in in the upcoming assessment report, through collaborations with external data visualisation professionals, which is a move in the right direction.
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