Key messages:

More than half the global population – around 4.5 billion people – are at high risk of experiencing an extreme weather event, such as a flood, drought, cyclone, or heatwave. About 2.3 billion of them are poor (living on less than $6.85 per day), and almost 400 million are extremely poor (living on less than $2.15 per day), according to 2020 data.

Poverty is not the only driver of vulnerability, and many non-poor households are vulnerable to experiencing severe impacts or welfare losses.

Hazard, exposure, and vulnerability all determine the impact of an extreme weather event on people. Hazard is the potential occurrence of an extreme weather event, exposure refers to who or what could be affected by the weather event, and vulnerability estimates the degree to which these people may be adversely affected.

This study considers a household vulnerable to extreme weather events if it is highly likely to experience severe losses – including lack of access to basic infrastructure such as water and electricity – and unable to cope with and recover from losses. Households are considered unable to cope if they do not have enough income to manage the impact of a shock, are not able to adapt their livelihood to reduce income losses, do not have access to social protection, or do not have access to financial services. People who are vulnerable on one of these dimensions are considered highly vulnerable to extreme weather events.

Given the large number of people exposed to extreme weather events – and the large share of them who are poor or highly vulnerable – countries need to act urgently to mitigate the impacts of climate change and help people adapt to these risks and protect their welfare.

Estimates from 75 countries covering 77 percent of the world’s population, where data on all indicators were available, suggest that 42 percent of the total population (and 70 percent of people exposed) were at high risk from extreme weather shocks in 2019.

The trend between 2010 and 2019 can be explored in a subset of countries covering 60 percent of the world population. In these countries, even though the number of people exposed to extreme weather events has been increasing, the number at high risk has declined. The exception is Sub-Saharan Africa, where the number of people at high risk has increased between 2010 and 2019.