Climate change-associated suicide risks: Global evidence, income inequalities, and limited evidence of adaptation

Climate change has been associated with adverse mental health outcomes worldwide, yet cross-country heterogeneity in climate–suicide associations and potential evidence of adaptation remain insufficiently understood. Here, using longitudinal analysis of income-stratified data across 116 countries, we identify heterogeneous associations between climate variables and suicide rates across development levels. In low-income countries, precipitation declines are associated with higher suicide rates, potentially reflecting socioeconomic vulnerabilities such as food insecurity. Middle-income populations exhibit gender-specific association patterns, where wind speed elevates male suicide while temperature raises female suicide risk. These patterns are only tentatively consistent with dysthymia-related associations, whereas similar associations are not observed for major depressive disorder or anxiety disorder outcomes. Accordingly, these observations should be interpreted as exploratory and hypothesis-generating rather than evidence of specific psychological mechanisms. In high-income countries, reductions in solar radiation are associated with increased suicide risk of ∼4.5% per Wm⁻² decrease both for males and females, suggesting possible environmental sensitivity despite comparatively greater socioeconomic resources. Across all development stages, climate–suicide associations remain relatively stable over time, suggesting limited evidence of adaptation under the current analytical framework. Projections indicate 98,000 (95% CI: 2.5k to 526k) excess male and 42,000 (95%CI: 2k to 213k) excess female suicides in high-income countries by 2035 under current emissions trajectories. Overall, the findings suggest that climate–suicide associations may vary across socioeconomic contexts, while the proposed interpretations regarding underlying processes remain untested and require further investigation.