The emerging threats of climate change on tropical coastal ecosystem services, public health, local economies and livelihood sustainability of small islands: Cumulative impacts and synergies

• Climate change and sea level rise have impacted tropical islands at a global scale.
• Impacts have resulted in declining local economies, livelihoods and public health.
• Changes may enhance vulnerabilities through a combination of feedback mechanisms.
• Multi-level, multi-sectorial responses are necessary for adaptation to be successful.
• Rapid adaptive responses are necessary before impacts become irreversible.

Climate change has significantly impacted tropical ecosystems critical for sustaining local economies and community livelihoods at global scales. Coastal ecosystems have largely declined, threatening the principal source of protein, building materials, tourism-based revenue, and the first line of defense against storm swells and sea level rise (SLR) for small tropical islands. Climate change has also impacted public health (i.e., altered distribution and increased prevalence of allergies, water-borne, and vector-borne diseases). Rapid human population growth has exacerbated pressure over coupled social–ecological systems, with concomitant non-sustainable impacts on natural resources, water availability, food security and sovereignty, public health, and quality of life, which should increase vulnerability and erode adaptation and mitigation capacity. This paper examines cumulative and synergistic impacts of climate change in the challenging context of highly vulnerable small tropical islands. Multiple adaptive strategies of coupled social–ecological ecosystems are discussed. Multi-level, multi-sectorial responses are necessary for adaptation to be successful.