A new global study has found that nearly 19% of the world population is at high risk from climate related disasters, with researchers warning that billions of people are already exposed to dangerous environmental conditions linked to droughts, floods, heatwaves and cyclones.
The research combined household-level vulnerability data with local exposure to four major climate hazards agricultural droughts in rural areas, floods, extreme heatwaves, and tropical cyclones across 160 countries in 2021.
According to the findings, around 4.5 billion people are expected to experience at least one of these hazards at intensities severe enough to trigger major social and economic impacts during their lifetime.
Researchers identified “high risk” populations as people who are not only exposed to climate hazards but also highly vulnerable because of limited financial resources, poor infrastructure, weak healthcare systems, or lack of social protection.
The study found that Sub Saharan Africa faces the world’s highest vulnerability levels. In many countries across the region, nearly everyone exposed to climate hazards is also considered highly vulnerable, significantly increasing the potential for humanitarian crises and long-term economic damage.
Vulnerability rates in Sub Saharan Africa ranged from 8% to 71% across most social and economic indicators examined in the study. Researchers noted that access to finance remained a major challenge not only in Sub-Saharan Africa but also in the Middle East and North Africa, where financial vulnerability rates reached 39%.
In contrast, Asia recorded higher average exposure to climate hazards because of its large population and frequent extreme weather events, but overall vulnerability levels were comparatively lower. Researchers attributed this partly to stronger infrastructure, better access to services, and wider economic resilience in several Asian countries.
The study also highlighted sharp regional contrasts between North America and Latin America and the Caribbean. While both regions showed similar levels of population exposure to climate hazards, the proportion of people classified as high risk was much lower in North America because relatively few individuals met the study’s globally consistent thresholds for high vulnerability.
Researchers said the findings demonstrate that climate risk is shaped not only by exposure to disasters but also by social inequality, poverty, and the ability of communities to prepare for and recover from extreme events.
The report underscores growing concerns among scientists and policymakers that climate change is increasingly interacting with economic and social vulnerabilities, creating compounding risks for billions of people worldwide.