This chapter, titled "Sea Level Rise and Implications for Low-Lying Islands, Coasts and Communities," provides a comprehensive assessment of the impacts and responses to rising sea levels. It is authored by a team of international experts and structured into several sections, covering the physical basis for sea level change, observed and projected impacts, and response options. Key findings include: - Global mean sea level (GMSL) is rising and accelerating, with the dominant source of rise being the contribution from glaciers and ice sheets. - Non-climatic factors, such as human activities and subsidence, have significantly increased the exposure and vulnerability of coastal communities to sea level rise (SLR) and extreme sea level events (ESL). - Coastal ecosystems are already impacted by SLR and other climate-related changes, but their ability to adapt is limited by human activities. - Coastal risk is dynamic and expected to increase significantly by the end of the century, with high to very high risks projected for many low-lying coastal settings under high emission pathways. - Responses to SLR include protection, advance, ecosystem-based adaptation (EbA), accommodation, and retreat, each with its own advantages and challenges. - Effective responses require a tailored approach that considers local conditions and involves coordinated planning, public participation, and conflict resolution. The chapter emphasizes the need for ambitious and sustained mitigation efforts to contain SLR and effective adaptation actions to reduce impacts and risks. It also highlights the importance of addressing governance challenges and social choices in the context of SLR.This chapter, titled "Sea Level Rise and Implications for Low-Lying Islands, Coasts and Communities," provides a comprehensive assessment of the impacts and responses to rising sea levels. It is authored by a team of international experts and structured into several sections, covering the physical basis for sea level change, observed and projected impacts, and response options. Key findings include: - Global mean sea level (GMSL) is rising and accelerating, with the dominant source of rise being the contribution from glaciers and ice sheets. - Non-climatic factors, such as human activities and subsidence, have significantly increased the exposure and vulnerability of coastal communities to sea level rise (SLR) and extreme sea level events (ESL). - Coastal ecosystems are already impacted by SLR and other climate-related changes, but their ability to adapt is limited by human activities. - Coastal risk is dynamic and expected to increase significantly by the end of the century, with high to very high risks projected for many low-lying coastal settings under high emission pathways. - Responses to SLR include protection, advance, ecosystem-based adaptation (EbA), accommodation, and retreat, each with its own advantages and challenges. - Effective responses require a tailored approach that considers local conditions and involves coordinated planning, public participation, and conflict resolution. The chapter emphasizes the need for ambitious and sustained mitigation efforts to contain SLR and effective adaptation actions to reduce impacts and risks. It also highlights the importance of addressing governance challenges and social choices in the context of SLR.