The 2025 small island developing states report of the Lancet Countdown on health and climate change: building resilience in the face of rising heat

Small island developing states (SIDS) are particularly vulnerable to climate change, and people living in SIDS continue to bear the brunt of its manifestations, including sea-level rise, droughts, floods, and extreme weather events. The vulnerability of SIDS stems from their size, remoteness, geographical locations, and small economies. Collectively, SIDS produce less than 1% of the global greenhouse gas emissions, yet climate change presents an existential threat to them. In this report, we shed light on the disproportionate impact of climate change on SIDS and progress towards achieving the goals of the Paris Agreement by presenting the findings of specific indicators at the climate change–health nexus in SIDS. In this second iteration of the SIDS report, we present the findings of 28 indicators from five thematic areas: health hazards, exposures, and impacts; adaptation, planning, and resilience for health; mitigation actions and health co-benefits; economics and finance; and public and political engagement in health and climate change. The report is compiled by 30 authors from 25 institutions. General statements about SIDS were only made for indicators with data coverage of at least 70%, with the number of SIDS with available indicator data explicitly stated when this threshold was not met. The 2025 report includes a dedicated chapter on financing with a deep dive into international climate financing for SIDS.