Climate change, national vulnerability and personal anxiety among teenagers and adults in 108 countries: an instrumental variable analysis

The latest Assessment Report from the Intergovernmental Panel on Climate Change (2022) stated for the first time "with high confidence [that] climate change is human made." However, this scientific fact has not elicited widespread belief even among democratic representatives, let alone its mental health impact being universally recognised. Using the latest survey in 2020 of extreme anxiety among 113,460 teenagers and adults in 108 countries which constitute 89% of the world population, I ask whether personal belief in climate change drives extreme anxiety. Such a causal link arises when urgent actions endorsed by the Panel are only slowly heeded by governments while personal lifestyle changes are perceived as hardly sufficient, creating chronic dissonance. But there may be other drivers not elicited in the survey eg, personal action on climate change and exposure to misinformation (eg: a democratic representative claims that government geoengineers hurricanes which harm health, instead of their increased frequency being a manifestation of climate change). To overcome potential bias, I use fixed effect instrumental variable analysis (instruments: country average belief in science today and two years previously). This is complemented with a placebo test, heterogeneity analysis across gender, sensitivity analysis (random effect) and mechanistic analysis across nations with different levels of vulnerability. I found that personal belief in climate change raises the probability of extreme anxiety by 12% (confidence interval 6-17%). And national context matters a great deal. Together they suggest that the less-than-urgent actions on climate by governments already harm mental health around the world. The nexus of effective climate action by governments and health benefits for citizens represents a synergy between two sustainable development goals which commend themselves to immediate action.