Evidence-based communication on climate change and health: Testing videos, text, and maps on climate change and Lyme disease in Manitoba, Canada

communication campaign by the Government of Canada, showing high awareness of Lyme disease but low rates of adopting preventative behaviours. Indication of participants adopting behaviours to mitigate climate change after seeing the materials was even lower, indeed, no participants said they would change their behaviours to act on climate change. The shift from attitudinal change to behavioural change is a well-known challenge in psychological research, and communication materials must stimulate deeper engagement with the issue, particularly through an emotional connection, which seemed to best demonstrated through the use of video in our study. Adapting the materials and implications for other CIWs Based on the findings of this study, the tested communications materials were revised based on participant feedback to increase their efficacy, and were ultimately published on the Cli- mate Atlas of Canada to support evidence-based content development of the climate informa- tion website (CIW) [56]. While the participant responses here provide insight for CIW content development, the process of materials testing and adaptation also provides insight into an approach for future evidence-based materials development in climate communications. Changes made to the materials and considerations and recommendations for CIWs are sum- marized in Table 3. Not all feedback was incorporated in the revised materials, in part due to limitations of cli- mate model data and visualizations, but also because of opposing feedback from participants.

In alignment with previous research, the results here show that different audiences along the climate concern spectrum require different materials and framing, and thus user-testing can help refine materials to increase their efficacy across audiences. This might also help avoid Table 3. Summary of changes made to the materials and recommendations for future online climate communications based on current findings. Article Video Map Changes made to the materials in response to participant feedback ✓ Clarified technical language ✓ Included additional images to accompany the text ✓ Added more information on Lyme disease symptoms and illness representation ✓ Added more information from the story of the person with lived experience of the disease ✓ Added more of the messengers that participants found most engaging (e.g. person with lived experience and medical doctor) ✓ Added specific visuals that participants requested (e.g. comparisons of different tick species, pets, and tick habitat) ✓ Changed the colour ramps to use less red and make the colours less bright ✓ Eliminated technical terminology and simplified the language in the map caption and legend ✓ Changed the language around the time periods shown and removed the 2015 Lyme disease risk areas ✓ Added a map to visualize a lower carbon pathway (RCP 4.5) to show how climate action could lessen the spread of Lyme disease Recommendations for CIWs and considerations for future climate communications research ➢ Continue to refine best practices for using simple language to communicate complex climate impacts

➢ Attention to which sources (academic or non-academic) are most credible to different audiences ➢ Create different length videos to reach different audiences ➢ Include more relatable messengers, particularly those with lived experience of health impacts ➢ Explore collaborations for sharing content across platforms to reach different audiences ➢ Attention to emotions evoked by certain colour ramping on climate maps ➢ Accompany climate visualizations such as map projections with information on how to interpret ➢ Embed maps in other materials where they can be contextualized for unfamiliar audiences • Creative, visual mediums of communication are most effective, but diversity is important. Incorporating elements of storytelling and relatable visuals into communication products are most effective at engaging people. • Climate communicators should explore how to better integrate content into platforms and contexts that are already relevant to audiences (e.g. share information through outdoor magazines, parks, hunting and fishing guides, TV commercials, doctors’ offices, etc.). • Climate communicators should be reflective of when and how maps of climate projections are and are not useful for communicating to lay audiences versus professional users. There is a need for further user testing of maps and other climate visuals created for CIWs. https://doi.org/10.1371/journal.pone.0252952.t003 PLOS ONE Evidence-based communication on climate change and health PLOS ONE | https://doi.org/10.1371/journal.pone.0252952 June 10, 2021 12 / 17