Public versus expert knowledge and perception of climate change-induced heat wave risk: a modified mental model approach

Effects of climate change and its induced extreme environmental events have been the object of intense public debate in recent years. Extreme environmental events, such as heat waves, and their impact upon the elderly and the poor are of special concern to policy- and decision-makers. However, how the public views these issues is critical for dealing with the associated risks. Recognizing the importance of risk assessments and implementation of mitigation measures, we adopted a comparative approach to assess and extend a generic methodology to examine diverse sets of beliefs about climate change-induced heat wave hazards. Using a modified mental model approach, this study mapped existing knowledge structures about the risk associated with climate change-induced heat waves in an urban setting of Canada (Winnipeg, Manitoba). 'Public models' were developed from open-ended interviews with diverse community groups; 'influence diagrams' were formulated based on open-ended discussions with experts in the pertinent fields. An assessment of the juxtaposition of the public and experts' knowledge and perception of heat wave risk has revealed significant gaps in the perception of: (a) the effects of climate change-induced heat wave and (b) of responsible authority for policy intervention to affect the cause or impacts. It further identifies misconceptions in public perception regarding: (a) thinning of ozone layer to cause a rise in earth's temperature; and (b) whether precautionary measures can be taken to reduce heat wave mortality; (c) of future heat wave 'risk estimation' in the city of Winnipeg. Based on our results, we argue that by developing interactive risk communication tools and practicing public engagement in knowledge enhancement, heat wave risk assessment and mitigation capacity of both public and experts can be improved.