Climate Change and Well-being: Science20 (S20) South Africa 2025 Statement

This statement was prepared by the National Academies of Sciences of the G20 states under the leadership of the Academy of Sciences of South Africa (ASSAf) to provide scientific advice to the G20 Summit of Heads of State and Governments in South Africa in 2025. Climate change remains one of the most urgent challenges of our time, with far-reaching consequences for human and planetary well-being. It threatens health, livelihoods, and the stability of Earth’s life-support systems—especially for people in vulnerable situations. The Intergovernmental Panel on Climate Change (IPCC) bases its assessments about climate change on decadal and multi-decadal averages, not single-year observations. The year 2024 was designated as the warmest year on record due to incremental global warming trends. Since the industrial era, unequivocal historical and ongoing human activities have been the primary drivers of climate change, far outweighing natural phenomena like solar variations, volcanic activity, ocean circulation patterns, and natural greenhouse gas emissions. Responding to the effects of climate change requires urgent, science-based solutions for mitigation and adaptation, informed by evidence-driven policy and global cooperation. While climate change poses risks and trade-offs, addressing it also creates opportunities for innovation and delivers multiple co-benefits for health, ecosystems, and the economy. The 2025 Science20 (S20) focus on Climate Change and Well-being aligns with South Africa’s G20 theme Solidarity, Equality, and Sustainability. This Statement outlines five areas, each with supporting recommendations.