Impact of cumulative exposure to extreme weather events on intermediary pathways of climate-related mental health: Evidence from a nationally representative Australian youth survey

Introduction: Recent years have seen growing recognition of the mental health toll that climate change imposes on younger generations. In response, researchers, clinicians, and practitioners are increasingly seeking to address climate-related distress through a range of clinical, community and school-based approaches. There now exists emerging evidence supporting a cumulative effects relationship between exposure to climate-related disasters and overall population mental health outcomes. However, it is unclear whether this applies specifically also for young people, or towards non-pathological intermediary factors influencing climate-related distress. Methods: Using cross-sectional, nationally-representative online survey data of young Australians (aged 16-25 years), we fitted logistic regression models exploring associations between cumulative extreme weather exposure, and five outcomes of interest: (1) climate concerns, (2) climate concern’s impact on mental health, (3) self-reported overall mental health, (4) climate-related factors impacting mental health, and (5) perceived helpfulness of climate anxiety supports. Secondary stratified analyses of these regressions were conducted exploring model variations by gender, age sub-groups, and geographic remoteness. Results: Weighted analyses demonstrated clear cumulative effects relationships between cumulative exposure to extreme weather events and higher likelihood of climate concern, reporting increased concern within 12 months of survey completion, and self-reporting poor mental health. Event-specific effects were most consistent for heatwaves and bushfires/bushfire smoke, which were associated with heightened climate concern and stronger perceptions that factors such as government inaction, environmental policy uncertainty, and worry about the planet negatively affecting young people's mental health. Cumulative exposure showed the strongest and broadest associations, with those exposed to more types of events more likely to view all proposed supports (clinical, educational, and structural) as helpful. Stratified analyses suggested stronger cumulative effects patterns for female/other gender groups and for young people aged 22–25, though precision was limited by small subgroup sizes. Conclusion: Extreme weather exposure is now a near‑normative experience for Australian youth and is associated with measurable impacts on climate concern, perceived drivers of mental health burden, and preferred support pathways. The consistent cumulative effects patterns observed highlight the cumulative mental health burden of living through multiple climate hazards, with heatwaves and bushfires/smoke showing particularly salient associations. These findings reinforce the need to integrate mental health into climate adaptation and emergency management strategies and policies, and emphasise the importance of institutional and upstream responses alongside targeted supports for highly exposed young people.