Focus on the Impact of Natural Events.

 

The ETR impact of natural events indicator measures how dangerous climate-related disasters – such as floods, storms, or heatwaves – are likely to be for populations. It accounts not only for the severity of environmental hazards but also for how many people are exposed and how well they are able to cope. The measure combines three elements at the subnational level: climate risk, population density, and poverty levels. This approach recognises that the consequences of natural hazards are shaped both by the scale of exposure and by the resources available to respond. Hazardous natural events have caused over 260 million internal displacements worldwide since 2015. The number of such movements has grown over this period, driven partly by more frequent and intense hazards but also by stronger national reporting and improved global monitoring. In 2024 alone, natural hazards caused 45 million displacements across 163 countries – the highest annual total since at least 2008. Storms and floods made up the vast majority of these displacements, affecting wealthy and poorer countries, though their long-term impacts were most severe in low-income settings. By the end of 2024, 9.8 million people remained displaced as a result of disasters. It is noteworthy, however, that natural disasters tend to cause more temporary displacements than conflict. In comparison to the over 45 million new disaster displacements in 2024, conflict caused about 20 million new movements last year. However, while the stock of those displaced by disaster was 9.8 million at year’s end, the stock of those displaced by conflict stood at 73.5 million, reflecting a build-up over many years of people unable to return home.

The 2025 ETR identifies 336 subnational areas with very high levels of exposure to the impact of natural events and a further 616 with high levels, encompassing more than half of the global population. 

This year marks the highest share of the global population exposed to very high risk, with the number of people living in these areas rising by 55% in the last five years. As shown in Figure 1.15, sub-Saharan Africa and South Asia faced the highest risks from natural events, driven by a combination of high climate vulnerability, dense populations, and limited adaptive capacity. In these regions, floods, droughts, and storms are more likely to escalate into humanitarian crises. In contrast, Western and Central Europe recorded much lower levels of risk, reflecting stronger infrastructure and more effective governance, which enhance their capacity to withstand and recover from environmental shocks. As shown in Table 1.4, Burundi recorded the highest risk score in impact of natural events indicator, with all its subnational areas recording very high risk levels in 2024. With most of its population reliant on rain-fed farming, the recent experiences of recurrent floods, droughts, and soil erosion have had direct impacts on food supply and livelihoods. This dependence is intensified by severe land degradation, leaving households with little capacity to absorb environmental shocks.

 Over the past five years, countries have experienced diverging trajectories in their exposure to natural hazards. Nine of the ten largest deteriorations were concentrated in West Africa, where rapid population growth and limited infrastructure heighten the impact of natural events. Liberia, Burkina Faso, and Nigeria recorded the biggest deteriorations, with rising scores indicating greater vulnerability to floods, storms, and droughts. Conversely, the largest improvements were not specific to any region, with Guyana, North Korea, and Russia registering the largest improvements, alongside advanced economies such as Spain and Australia. At the regional level, sub-Saharan Africa recorded the largest deterioration in the impact of natural events between 2019 and 2024, as shown in Figure 1.16. It was followed by South Asia and the Middle East and North Africa. Environmental pressures are intensified by poverty, fragile governance, and rapid population growth, increasing the likelihood that hazards translate into disasters. In contrast, Western and Central Europe recorded notable improvements. These changes mirror the region’s improvements in water risk, where an unusually severe 2019 baseline of heatwaves and drought made subsequent conditions in 2024 appear far more favourable as they returned closer to historical norms. In addition, these patterns may also suggest the widening gap between risks in low-income countries, which remain extremely vulnerable to climate hazards, and higher-income regions where risks are stabilising or even declining. In some ways this is to be expected as rich countries with good governance and high societal resilience scores are more likely to better manage their ecological weaknesses

Since the 1980s, the number of documented climate-related disasters has more than doubled, according to the records of the Emergency Events Database (EM-DAT). In 1980, just over 100 climate-related disaster events were recorded, but by 2023, this figure had risen to more than 370. As shown in Figure 1.17, most of this increase has been driven by increases in floods and storms, which together accounted for more than 80% of all climate disasters recorded in 2023. However, since 2005 the number of events has roughly remained the same.

It is important to note that some of the observed increase in recorded disasters in recent decades may be the result of improvements in monitoring and reporting. Coverage in earlier periods was patchy, with smaller and medium-sized events often going unrecorded. The steep increase in numbers during the late 20th century coincided with advances in communication technologies, the creation of dedicated Disaster databases, and greater institutional interest in compiling records.

Moreover, with these improvements in monitoring and reporting, evidence suggests that natural disasters have become significantly less deadly. Despite population growth and climate change, the likelihood of dying in a storm, flood, or drought is now far lower than it was in the 20th century. Research has found that global disaster deaths have fallen from a rate of more than 25 annual deaths per 100,000 people a century ago to fewer than 0.5 annual deaths per 100,000 people today. In Bangladesh, for example.

cyclones that once killed hundreds of thousands in the 1970s and 1980s now claim only a fraction of that toll, thanks to advances in forecasting, early warning systems, community preparedness, andstronger infrastructure. Globally, similar improvements in agriculture, public health, and governance have reduced vulnerability. This demonstrates that while hazards themselves have not disappeared – and in many cases have become more severe – investment in resilience saves lives on a massive scale. In view of the reporting complications prior to 2000, the trends inclimate-related disasters over the past two decades are further outlined in Table 1.5. The table highlights just how variable the profile of climate-related disasters has been in the 21st century. Floods are by far the most common, with more than 200 recorded events in several years, including peaks in 2006, 2007, and 2021. Storms are the second most frequent, consistently numbering between 80 and 140 events per year, while droughts, wildfires, and extreme temperature events are recorded far less often but still show important spikes – such as droughts in 2015 and 2022, or extreme heat events in 2012 and 2022. The pattern suggests both an overall upward trend in reporting and a shifting mix of hazards, with floods and storms accounting for the majority, but heatwaves and droughts increasingly punctuating the record in recent years. This evolving distribution underlines how multiple climate hazards are now interacting, creating complex risks for governments and communities alike.

The costs of climate-related disasters to the global economy have been substantial. Between 2000 and 2019, climate-related disasters generated nearly $3 trillion in losses, with multi-hazard events – such as cyclones that simultaneously destroy cropland, trigger flooding, and spark disease outbreaks – responsible for almost 60 per cent of damages. Such impacts are not merely additive but compounding, as overlapping crises can overwhelm institutions and stretch recovery capacities. The humanitarian toll is also severe. Floods and cyclones disrupt water and sanitation systems, heightening the spread of diseases such as cholera and diarrhoea. Heatwaves and prolonged droughts erode agricultural production, exacerbating malnutrition and threatening food security in fragile states. Repeated shocks drive households into cycles of debt, asset loss, and displacement. Pastoralist communities may lose entire herds during extended droughts, while coastal populations confront declining fisheries and infrastructure damage from storm surges. These cumulative effects reduce resilience and magnify the difficulty of recovery after each successive disaster. Collectively, these effects demonstrate that natural events should not be seen as isolated shocks, but as catalysts of longer-term developmental decline. Building resilience requires more than physical protection; it demands integrated investments in health systems, food security, and livelihoods that can withstand repeated and compounding pressures.