The report highlights that over a million residents in low-lying areas across the Pacific, Caribbean, Indian Ocean, and South China Sea regions could be displaced as sea levels rise. This is compounded by severe food insecurity as marine ecosystems destabilize, leading to higher rates of chronic health issues such as obesity and diabetes. "Heat is one of the primary challenges," said Georgiana Gordon-Strachan, director of the Lancet Countdown Centre for SIDS, citing its impacts on human health, the marine environment, and extreme weather events.

The study found that extreme heat waves, amplified by the warming oceans, are fueling monster storms and eroding labor capacity, with 4.4 billion work hours lost in 2023 alone—71% higher than averages recorded in the 1990s. "The ramifications of a warming world are devastating, from extreme weather events to the loss of homes, lives, and livelihoods," Gordon-Strachan warned, adding that some islands may be submerged entirely if the current trends persist.

The crisis also brings new public health risks. Changing weather patterns have increased the potential for diseases like dengue by one-third since the 1950s. Meanwhile, as agriculture and fisheries suffer, island nations are shifting towards processed, imported foods, exacerbating health problems and reducing the ability for outdoor exercise due to extreme heat.

Despite SIDS' low contribution to global greenhouse gas emissions, the report calls for "ambitious and concerted action" by wealthier countries to cut emissions and help mitigate climate impacts. However, health systems in most small island nations are ill-prepared for the crisis. Only eight of the 59 SIDS examined have national climate and health strategies, and a lack of data hampers efforts to identify vulnerable populations and monitor progress.

At COP29 in Baku, SIDS negotiators walked out in frustration as their calls for stronger action went unheeded, reflecting growing disillusionment among the world's most climate-vulnerable nations. "This report is a clarion call for action," Gordon-Strachan said. "What are we waiting for?"

The authors warn that without immediate international cooperation, the escalating climate crisis could push small island nations beyond the brink, resulting in widespread displacement, loss of culture, and devastating impacts on global health systems. "The trajectory is clear, and it is catastrophic without urgent intervention," said co-author Roannie Ng Shiu from the University of Auckland.