Climate change-induced sea-level rise in the world's 52 small island nations - estimated to be up to four times the global average - continues to be the most pressing threat to their environment and socio-economic development with annual losses at the trillions of dollars due to increased vulnerability. An immediate shift in policies and investment towards renewable energy and green economic growth is required to avoid exacerbating these impacts, says a new report by the UNEP. In all SIDS regions, coral reefs, the frontline for adaptation, are already severely impacted by rising sea surface temperatures. The global net loss of the coral reef cover - around 34 million hectares over two decades - will cost the international economy an estimated US$11.9 trillion, with Small Island Developing States (SIDS) especially impacted by the loss. The SIDS Foresight Report identifies climate change impacts and related sea-level rise as the chief concern among twenty emerging issues impacting the environmental resilience and sustainable development prospects of SIDS - including coastal squeeze, land capacity, invasive alien species and threats from chemicals and waste.