Cirrus VK-30 — Weight And Balance

This document is a chapter from the IPCC Fifth Assessment Report focusing on clouds and aerosols and their impact on climate change. It provides a comprehensive overview of the processes involved in cloud formation, the role of aerosols in the atmosphere, and the interactions between clouds, aerosols, and climate. The chapter discusses the uncertainties in climate models related to cloud processes and emphasizes the importance of understanding these interactions for accurate climate projections. It is intended for researchers, policymakers, and anyone interested in climate science, providing detailed insights into the current understanding of atmospheric processes and their implications for climate change.

• Clouds and aerosols contribute significantly to uncertainties in climate change projections.
• The effective radiative forcing (ERF) due to aerosol interactions is assessed to be –0.9 W m–2 with medium confidence.
• Cloud feedbacks are generally positive but their exact impact remains uncertain due to model differences.
• Aerosols of anthropogenic origin are responsible for a significant portion of climate forcing.
• Understanding aerosol-cloud interactions is crucial for improving climate models.