Do Americans Understand That Global Warming Is Harmful to Human Health? Evidence From a National Survey

Background: Global warming has significant negative consequences for human health, with some groups at greater risk than others. The extent to which the public is aware of these risks is unclear; the limited extant research has yielded discrepant findings. Objectives: This paper describes Americans' awareness of the health effects of global warming, levels of support for government funding and action on the issue, and trust in information sources. We also investigate the discrepancy in previous research findings between assessments based on open- versus closed-ended questions. Methods: A nationally representative survey of US adults (N = 1275) was conducted online in October 2014. Measures included general attitudes and beliefs about global warming, affective assessment of health effects, vulnerable populations and specific health conditions (open- and closed-ended), perceived risk, trust in sources, and support for government response. Findings: Most respondents (61%) reported that, before taking the survey, they had given little or no thought to how global warming might affect people's health. In response to a closed-ended question, many respondents (64%) indicated global warming is harmful to health, yet in response to an open-ended question, few (27%) accurately named one or more specific type of harm. In response to a closed-ended question, 33% indicated some groups are more affected than others, yet on an open-ended question only 25% were able to identify any disproportionately affected populations. Perhaps not surprising given these findings, respondents demonstrated only limited support for a government response: less than 50% of respondents said government should be doing more to protect against health harms from global warming, and about 33% supported increased funding to public health agencies for this purpose. Respondents said their primary care physician is their most trusted source of information on this topic, followed by the Centers for Disease Control and Prevention, the World Health Organization, and their local public health department. Conclusions: Most Americans report a general sense that global warming can be harmful to health, but relatively few understand the types of harm it causes or who is most likely to be affected. Perhaps as a result, there is only moderate support for an expanded public health response. Primary care physicians and public health officials appear well positioned to educate the public about the health relevance of climate chang