A quantitative evaluation of the public response to climate engineering: Reply to Gardner – Guest Post – Malcolm J. Wright, Damon A.H. Teagle and Pamela M. Feetham


Wednesday, Aug. 13, 2014

Professor Meryl P. Gardner recently published a comment in this forum discussing our article on the likely public reaction to climate engineering. We thank Prof. Gardner for her thoughtful discussion, and for the positive comments on much of our work. While we have some areas of disagreement, we think critical discussion is an important part of the scientific process, so we welcome her remarks.

Perhaps the most substantial point raised by Prof. Gardner is the question of whether people will in fact make choices based on associative or on deliberative thinking. We agree this is an important issue. To date, the evidence suggests that associative thinking is far more common than we might suspect or perhaps approve1 and so it is the most important area for an initial large-scale, controlled, quantitative study.2 It may be desirable to foster deliberative thinking in place of associative thinking on topics such as climate engineering. Yet, how might this be encouraged? How much deliberative thinking will occur spontaneously? Is deliberative thinking a switch to a different cognitive process, or movement along a continuum of mental activation and elaboration? These questions concern us too, and form the basis for our ongoing work in this area. We look forward to completing and publishing that work in due course.

Prof. Gardner raises concerns about the construction of the images, the selection of the attributes, the impact of more detailed learning, and the relative importance of attributes, although she kindly acknowledges the meticulous work we did to minimize biases in many of these areas. We can offer further reassurance on these points. On image selection, we followed the principle of using the best available public image provided by experts, rather than constructing our own. This ensured that the images were as representative as possible of what the public was actually likely to see, maximizing the external validity of our research. Further, the primary purpose of the images was to reduce the risk that some semantic elements of the concept statement would become over-salient. We believe our images achieved this objective and remain confident that our approach was sufficient to avoid validity threats. There is scope to systematically investigate the effects of image framing on climate engineering concepts; however, this was not the purpose of our work.

Our extensive program of qualitative research, preceding the development of the survey instrument, addresses many of the remaining concerns. The 30 depth interviews engaged respondents in additional learning while avoiding prompting particular types of attributes. The interviews elicited a far broader range of attributes than those ultimately used, and truncated them in a way that was representative and retained content validity. The qualitative attribute elicitation procedure also unambiguously anticipated one of the key findings of the quantitative research; that people view Solar Radiation Management techniques more negatively than they view Carbon Dioxide Removal techniques, providing some multi-method validation for our approach. We can also confirm that we followed the correct procedures for eliminating overlapping attributes using Kendal Tau-b correlations.3 So we are confident that our results are robust to Prof. Gardner’s concerns.

Our article introduces new ways of thinking about the public reaction to climate engineering, and new methods for measuring that reaction.

Prof. Gardner comments that initial negative responses may not predict increasingly negative reactions from individuals as they learn more about climate engineering. Here we agree, and we offer the following clarification. In describing techniques as becoming “more widely known” we did not intend to refer to the depth of knowledge held by the same individuals, but rather to the number of individuals who had any knowledge at all. We think it uncontroversial to suggest this will likely lead to more negative public reaction, particularly for Solar Radiation Management, but we agree with Prof. Gardner that this does not predict how people will react as they individually learn more about these techniques. This remains an important area for future research.

Conversely, while Prof. Gardner is concerned about the impact of unequal weighting of attributes, and the possibility of greater impact from negative attributes, we are unconvinced on either point. Without getting into a detailed discussion of stochastic memory theory, we can simply say that attribute weightings, or importance, will vary by individual, but these weightings can be added together to reach population means. Attributes with greater importance will generate more associations, so the overall association rate that we report reflects the average attribute strength. Similarly, while we agree that negative information may have greater impact under some circumstances, this is already adequately reflected in the association rate for the negative attributes. Prof. Gardner raises other points with which we agree: there may well be interesting sub-group differences in variables we have not yet examined; there is also much to be discovered about how people will learn about and engage with these techniques.

To conclude, our article introduces new ways of thinking about the public reaction to climate engineering, and new methods for measuring that reaction. As Prof. Gardner notes, such innovation inevitably prompts new questions. We hope that many more researchers will join us in investigating these questions. The role of associative thinking in scientific communication is an important field of study, and much remains to be done.


profile_032269_DCBA2D45-AEC3-0BAA-CA00593D22DD9993Malcolm Wright is Professor of Marketing and Deputy Pro Vice-Chancellor of the College of Business, Massey University. He is also Chair of the Australian Advisory Board for the Ehrenberg-Bass Institute for Marketing Science, an Associate Editor of the European Journal of Marketing, and Adjunct Professor at the University of South Australia.  Prof. Wright publishes widely in the academic and popular press, frequently appears in the New Zealand media commenting on branding and media issues, and has consulted to many organisations in North America, Australia and New Zealand.

Damon A.H. Teagle is Professor and Director of the Ocean and Earth Science, National Oceanography Centre at the University of Southampton, U.K.  

Pamela M. Feetham is a PhD student at the University of Massey, New Zealand, focussed on public reaction climate engineering proposals, involving interdisciplinary fields of marketing and science communication. 


1Kahneman, D. Thinking, Fast and Slow (Penguin, 2011).

2 Wright, M.J., Teagle, D.A.H. and Feetham, P. A Quantitative Evaluation of the Public Response to Climate Engineering. Nature Climate Change, 4, 106-110 (2014).

3Romaniuk, J. Modeling mental market share. Journal of Business Research 66,188-195 (2013).


The Washington Geoengineering Consortium does not necessarily endorse the ideas contained in this or any other guest post. Our aim is to provide a space for the expression of a range of perspectives on geoengineering.