India is the most flood-prone nation in Asia, with 622.1 million people—44% of its population—exposed to flood risks, according to a report by rating agency Moody's released on Thursday. Following India, China, Pakistan, Bangladesh, and Indonesia are the next most vulnerable countries.
Globally, more than 2.7 billion people, or over one-third of the world’s population, live in areas susceptible to inland or coastal flooding.
The growing frequency of floods worldwide highlights the urgent need to evaluate the demographic, geographic, and socioeconomic factors contributing to flood risks. These factors include physical location, infrastructure resilience, socioeconomic status, and climate variability.
Since 1975, the proportion of people exposed to flood risks has steadily risen due to climate change, urbanization, and land-use practices, leading to more frequent and severe flooding events. South Asia is the most flood-prone region, with nearly 40% of its population vulnerable to inland flooding and just over 5% exposed to coastal flooding, according to the Moody’s report.
In terms of inland flooding, China has 32% (453.2 million people) of its population at risk, Pakistan 61% (136.8 million), Bangladesh 73% (121.4 million), and Indonesia 38% (104.3 million).
On the other hand, Oceania is the least exposed region to inland flooding, with under 17% of its population at risk. From a coastal flooding perspective, Europe and North Asia have the lowest risk, with only 0.27% of their populations facing potential threats. South Asia stands in stark contrast to other regions, with a much larger population exposed to both inland and coastal flood risks.
“Flooding is a pervasive and recurrent natural hazard that has far-reaching consequences for both human communities and the environment,” Moody’s noted in the report. “As flooding continues to pose a growing threat, understanding the populations most vulnerable to its effects is paramount for effective disaster management and mitigation efforts.”
Moody’s estimates that approximately 2.4 billion people, or just over 31% of the global population, live in areas exposed to inland flooding at a 100-year defended return period. Around 2.3 billion of those people face a flood depth of more than 10 cm, representing 29% of the global population.
For coastal flooding, around 260 million people are exposed to some level of risk, with over 70% of them concentrated in just five countries. Of these, approximately 240 million individuals face a flood depth of over 10 cm, affecting just over 3% of the global population. At an increased flood depth of over 50 cm, the number of people at risk rises to 655 million for inland flooding and 200 million for coastal flooding.
