Aerosols—emitted from natural and anthropogenic sources—play critical roles in the Earth system from regional to global scales. They drive climate change through direct radiative effects (scattering and absorption) and indirect effects via aerosol–cloud interactions. Aerosols influence weather extremes by modulating cloud formation, atmospheric stability, and circulation. Due to the spatial heterogeneity of emissions and the complexity of their properties, understanding of aerosol impacts is more limited than for well-mixed greenhouse gases, remaining a major source of uncertainty in climate projections and hazard prediction.

This session focuses on the climatic and societal impacts of aerosols across scales. Topics include:

• Aerosol properties and emission changes from natural and anthropogenic sources;
• Aerosol effects on extreme events, past and future climate;
• Approaches and impacts of aerosol-based climate intervention (e.g., SAI, MCB);
• and broader health and societal implications.

Contributions based on laboratory experiments, observations, modeling (including RAMIP), theoretical approaches, and machine learning are all encouraged.

• GC - Global Environmental Change
• GH - GeoHealth
• NH - Natural Hazards
• SY - Science and Society