An interdisciplinary study on scientific visual communication in the context of climate change

Communication with society is imperative in many scientific fields, most notably climate science. Yet, climate change can be a fluid concept for the public to understand as it intrinsically uncertain and involves long time scales. Given the importance of the assessment reports published by the Intergovernmental Panel on Climate Change (IPCC) it is essential that this accrued evidence is accessible to policymakers. However, little is understood about how the representation of the science in these reports is perceived, comprehended and used in the decision process. This has only contributed to the overwhelming criticism of the IPCC communication approach, which arguably is not new information but has been apparent in the literature for some time now. Still, few have attempted to systematically evaluate how climate science is visually represented in the IPCC publications. This thesis attempts to fill this gap in understanding by examining how climate visualisations could be more effectively designed and communicated to non-technical audiences. In a first step, an empirical test was conducted on a central figure from the Summary for Policymakers (SPMs) published in the IPCC Fourth Assessment Report (AR4). The results highlight how novice readers, even highly educated ones, are unable to distinguish between different types of uncertainties shown without substantial guidance. Instead, readers saw a great deal of uncertainty in this figure but falsely attributed it to the climate model(s) and ignored the scenario uncertainties. The inability to distinguish between the various sources of climate uncertainties exemplifies the importance of rigorously pretesting SPM visuals. Following up on these findings, a further study was conducted to examine four visual devices typically used by Working Group I (WGI) in the SPMs for the IPCC AR4 and Fifth Assessment Report (AR5) plus two open sourced infographics. Pre-attentive visual features were found to significantly influence the judgement and confidence of readers. While the infographic supported the extraction of relevant information it was not considered to be as legitimate as the scientific looking SPM figures. Thus, providing further evidence that the design structure itself carries important perceptual information. Using an excerpt of the AR5 Synthesis Report (SYR) SPM the final study of this thesis examined the semantic arrangement of the text and visuals in this report. Certain improvement measures were implemented and the new layout was found to be more aesthetically pleasing and attractive than the original. Such findings illustrate that certain improvements in the visual communication can be achieved without altering the IPCC mandate and procedures. As the preparation work for the Sixth Assessment Report (AR6) begins, the timing of this thesis is highly relevant. While we can have no influence on the final outcome of the next assessment cycle, it is our intention to provide IPCC authors with timely and relevant guidance. This work has contributed to our greater understanding of visual communication in the context of climate change but it has also underscored some of the fundamental shortcomings in this research area