Perceptions of the health impacts of climate change among Canadians

Overall, the results find that levels of concern about health impacts are similar to levels of concern about biophysical, economic, and national security impacts of climate change among people in Canada. Water- and food-related impacts are of highest concern across classes and most common in response to the open-ended question. This differs from a previous Canadian survey in which air quality impacts were the most commonly named in response to an open-ended question [15]. Somewhat surprisingly, given recent discussion on these matters (e.g. [38]), mental health concerns ranked the lowest along with temperature-related impacts and infectious diseases, although there was significantly higher “worry about future generations,” compared with “stress from evacuation during extreme weather events,” and both were significantly higher than “personal climate anxiety.” The low concern about mental health impacts is interesting considering that climate change poses a serious threat to mental health in Canada [39], with some projecting mental health impacts to be among the costliest of all health impacts [40]. At the same time, mental health has been underrepresented in research on climate change and health historically [41, 42] and a recent survey found that only 44% of Canadian public health organizations report working on climate-related mental health risks [43]. This suggests that perhaps less information has been mobilized to the public regarding this pressing health issue and its linkage with climate change. Low concern about personal climate anxiety may also be due in part to the lack of widespread understanding and a common operational definition of the term [44, 45].

On the whole, these results illustrate the well-documented phenomenon of psychological distancing, which describes how people are more likely to believe the worst impacts of climate change are far away temporally, socially, and geographically [31, 46], and thus more likely to be concerned for the future generations than their own personal well-being. These beliefs have also been documented in southern Ontario, where people were more likely to describe impacts on their children or grandchildren than on themselves [16]. Even when the impact is local, such as the increased risk of Lyme disease due to changing temperatures in southern Manitoba, members of the public can perceive the risk as distant from themselves [17]. Recent research in the US shows that the spatial and temporal distribution of climate-related health impacts are far more immediate, localized, and costly than currently understood [47], which speaks to the need to carefully consider risk communications that take into account psychological distancing that may actually run counter to the best available climate and health sciences.

In some cases, concern about the health impacts of climate change parallels indicators of vulnerability across sociodemographic characteristics. Interestingly, older people (55+), and women consistently have higher concern regarding health impacts. Given that income, age, and gender are indicators of vulnerability to climate impacts generally [48], it is increasingly clear that those who are most affected by climate change are also more likely to be concerned about the impacts, and speaks to the larger health equity issues climate change poses for Canadians. These results are consistent with previous research in other parts of the world which has found a similar relationship between indicators of vulnerability and risk perception on climate change (e.g. [49‐51]).

Respondents reported considerable prior consideration of climate change health impacts, with just over half of Canadians responding high or very high on the question of how much they had thought about the connection between climate change and health, and only one fifth of respondents answered low or very low. By comparison, research in the US in 2014 found that only a third of Americans had thought about the health impacts of climate change “a great deal” or a “moderate amount” [4], while in 2020 significantly more Americans thought that climate change health effects would become more common [52]. While a substantial number of Canadians report having thought about the link between climate change and health, the results show that this consideration is not evenly distributed across the population. People with lower educational attainment and towards the right end of the political spectrum are significantly less likely to have thought about the link between climate change and health. Though perhaps unsurprising, this correlation between sociodemographics and the climate-health link indicates that there is a significant gap in awareness for half of the population, perhaps in part due to a lack of exposure to information on health impacts. At a global level, despite increasing public and scientific work on climate change and health [53], “in absolute terms, climate change continues to be framed in ways that pay little attention to its health dimensions” [54]. Public health agencies and units are poised as effective messengers on climate change health risks [4, 55, 56], and in some jurisdictions are mandated to communicate this information, such as the Canadian province of Ontario [57]. However, a recent survey of Canadian public health organizations found that only 48% of organizations had engaged in climate change and health education and outreach with the public, and only 36% had undertaken education or training on climate change and health risks and adaptation among staff or professionals [43]. Further health-focused climate communications campaigns (e.g. [58]) are needed to target those less engaged on climate change if we hope to reach widespread understanding of and participation in adaptive health behaviours, and the results of this Canada-wide study are helpful in this regard.

The results also found that the majority of respondents perceive climate change as harmful to human health, or are inclined to answer as such when prompted, despite approximately half of respondents not having thought a substantial amount about health impacts in particular. Similarly, a 2015 survey of Americans found that while only 10% of people had previously thought about climate change and health “a great deal,” 31% responded that climate change is “very bad” for health [4]. As Maibach et al. [4] suggest, this discrepancy could be in part due to people making inferences or momentary judgements about the negative impacts of climate change on health due to their general understanding of the issue, the context of the survey, and/or their suppositions about what the “right” answer is.

More than half of Canadians can name one or more health impacts of climate change when unprompted, with the most common impacts related to food security and agriculture, air quality, temperature related morbidity and mortality, and extreme events. Answers to open-ended questions such as this are likely more realistic representations of respondents’ true understandings of climate change and health as compared with close-ended questions that may prompt certain responses [4, 59]. Results here show a slight decline compared to previous surveys which found 69% of climate change believers in 2017 and 63% of Canadians in 2008 were able to identify one or more health impacts of climate change in response to an open-ended question [13, 15]. On the other hand, the results are significantly higher than a survey of US adults in 2015 which found that only 27% of respondents could name at least one health impact of climate change unprompted. The different coding schemes used to classify open-ended responses in these different surveys may be responsible for some of the variation in results. In general, however, the results here suggest that there has not been a notable increase in public knowledge on the health impacts of climate change over the past decade.

Engaging the public with focused, effective, and audience-specific communications on health-related climate issues has several potential benefits. The public health system can inform the public about health-related risks so that steps can be taken to prevent harm and to reduce risks [60]. In addition, communicating the health-related risks may be an effective way of increasing engagement in climate change issues [61]. The gap between awareness and action is well documented in the literature, and remains a major challenge for communicators and climate advocates [30, 62‐64]. Some recent literature points to a health framing as a potentially effective way to engage people across political and ideological divides [20, 21, 65], possibly because of a ‘ceiling effect’ where those on the left end on the political spectrum are already very concerned about the impacts of climate change [33]. However, our results found relatively low concern regarding climate health impacts among people whose political beliefs fall on the right end of the spectrum and suggests this may not hold true for this audience in Canada. In other studies, testing climate health framing, one found that public health framing in climate communications was effective at a local scale, but “backfired” for discussing impacts at a distance, and increased polarization across the climate concern spectrum [24]. Another study in Manitoba looking at climate change and Lyme disease similarly found a lack of resonance of climate health impacts with more sceptical audiences and suggested that health messages might be ‘strategically decoupled’ to best engage these audiences depending on the goal of the communicator [17, 66]. Results here suggest that for those less concerned about climate change, discussing the health impacts of climate change may not be more effective for engaging them than other climate change frames such as the economy. On the other hand, for communicating with those who are concerned about climate change, including those with higher educational attainment, health frames may be particularly beneficial, as this group is more concerned about impacts on health than impacts on national security and the economy. A summary of key findings and implications for health and climate communications are found in Table 2. Specific written and visual materials with health and non-health related frames were tested in the latter part of this survey study and the results will be published in a subsequent paper.

A significant limitation of the study was the sample size from Indigenous and racialized communities which was not sufficient to allow us to analyze results by ethnicity. This is an important limitation, given that racialized communities are disproportionately impacted by climate change now and into the future, including the health impacts of climate change, due to systemic marginalization and racism [53, 67]. In this way, the survey overlooked a large and potentially significantly at-risk portion of the population. Sufficient sample representation for comparison by race is also important considering previous research in the United States which has found that People of Colour are more often concerned about climate change impacts than white people [68]. Future surveys should ensure sufficient representation from Indigenous and racialized communities through more targeted recruitment and sampling, in order for the results to be applicable and useful to these communities.

Finally, the survey is limited in its scope given a finite number of variables that could be explored and the limitations inherent with measuring evaluative judgments. As Maibach et al. [4] explains, “evaluative judgments are not necessarily comprehensive representations of an individual’s “true” attitudes, but rather are based on momentarily accessible, salient information”. The context of the questions within the survey focused on climate change could have influenced participants’ responses. Additionally, the measures here (i.e. concern, awareness, affective assessment, and unprompted knowledge) do not necessarily fully capture issue value or importance. It is possible that people are not overly concerned about the climate health impacts presented, yet they do significantly value health, which may mean that we are underestimating the effectiveness of a health frame. The conclusions drawn with respect to applications in communications framings are limited given that these results just deal with perceptions and do not directly test health frames in communications materials. Test of health framing materials was done in a subsequent part of the survey and will be published in a future article.

Future research should seek further resolution of climate health perceptions and knowledge in Canada and the efficacy of health framing between demographics, geographic regions, and locally germane climate impacts. Studies testing the effects of specific climate and health communication campaigns on uptake of adaptive behaviours and support for policy change are also needed, as an alternative measure of the efficacy of these frames, and would contribute to the evolving literature on climate/health indicators [53]. Additionally, further exploration into the relationship between people’s personal health attitudes, experiences of climate impacts, and perceptions of climate health risks may shed more light on what informs and underlies the different perceptions found here.