A recent study has revealed for the first time that the residents of the world’s smallest nations, who contribute the least to climate change, are already suffering the most from its severe impacts, with expectations that their hardships will only increase.
A recent study has revealed for the first time that the residents of the world’s smallest nations, who contribute the least to climate change, are already suffering the most from its severe impacts, with expectations that their hardships will only increase.
Research conducted by the University of Bristol found that nearly one in five individuals (20%) living in Small Island Developing States (SIDS)—about 8.5 million people—are currently at risk of both coastal and inland flooding. In three of the 57 countries located in the Pacific, Caribbean, Indian Ocean, and South China Sea—namely, the Bahamas, Guyana, and Tuvalu—this figure rises to over 60% of the population, as stated by the study.
The findings are particularly pressing in light of extreme weather events, such as the recent severe flooding in Valencia, Spain, emphasizing the global threat of flooding.
According to Leanne Archer, a Research Associate at the University’s Cabot Institute for the Environment, “Flooding has become an alarming and tangible threat for countless individuals around the world. This study illustrates that the often-neglected Small Island Developing States are facing an incredibly high level of flood risk despite being among the least contributors to climate change.”
Looking ahead, projections indicate that even in the best-case scenario for global warming, the number of people vulnerable to hazards like rising sea levels, storm surges, and extreme rainfall—such as tropical cyclones—will increase significantly. In comparison, the number of individuals at risk in developed countries like the US and UK is notably lower, impacting approximately 13% and 8% of their populations, respectively.
Leanne added, “These findings should prompt urgent action to help these nations adapt to and mitigate the extreme effects of climate change, even with the most optimistic emissions forecasts putting lives and livelihoods at risk.”
SIDS refers to a collective of small island nations, with populations ranging from about 1,000 to 7 million, identified by the United Nations (UN) as particularly vulnerable to climate change. Coastal flooding poses a major risk due to high population densities in coastal areas, but the study also highlighted that inland flooding is a significant concern for SIDS, making up 81% of total population exposure.
Leanne, who conducted this research for her PhD on flood risk, remarked, “Earlier studies mainly focused on coastal flooding, which led to a serious underestimation of the risks involved. This research provides the first detailed overview of flood risk across all 57 Small Island Developing States, primarily because their smaller populations have not met the minimum threshold for earlier major global assessments.”
“The data compellingly shows how climate change has a disproportionate and unjust impact on those people and regions that have contributed the least to greenhouse gas emissions, which are fueling the crisis.”
Climate change exacerbates flooding risks in SIDS by amplifying factors like rainfall intensity, river flow, extreme wave heights, water levels, storm surges, and sea level rise.
Even if global temperature rise is limited to 1.5 degrees Celsius by 2100, over a fifth (21%) of the SIDS population is projected to be vulnerable to flooding. In a dire scenario with temperature increases of more than 4 degrees Celsius, that figure could climb to nearly a quarter (23%), as per the research. A previous UN report warned that without decisive action to cut carbon emissions, the world could face an increase of up to 3.1 degrees Celsius.
Regardless of the degrees of warming, the countries expected to be at the highest risk remained consistent in the projections, including Belize, the Turks and Caicos Islands, and the Maldives.
The study, carried out in collaboration with the University of Southampton, utilized data from water risk intelligence firm Fathom’s Global Flood Map, combining a high-resolution global hydrodynamic flood model with extensive population datasets.
Co-author Paul Bates, a Professor of Hydrology at the University of Bristol and co-founder of Fathom, stated, “This study addresses a critical gap in research, providing concrete measures of flood hazards and exposure, which are vital for minimizing loss and damage from flooding in the Small Island Developing States.”
“The findings serve as a crucial warning to global political leaders and policymakers that promises to substantially lower carbon emissions must be met with actual action to mitigate potential loss and damage from flooding in Small Island Developing States that are the least responsible for carbon emissions.”
Finding innovative solutions to significant global challenges lies at the core of the University of Bristol’s research mission. This study intersects key themes such as achieving net zero emissions, climate change, and social equity, while the Cabot Institute is committed to addressing urgent environmental changes, natural disasters, and risk management.