World Ecology Day

The 2025 Ecological Threat Report (ETR) is a comprehensive, data-driven global assessment of ecological risks . It covers 3,125 sub-national areas in 172 countries and territories, representing more than 99 per cent of the world’s population. It measures four interlocking threats: water risk, food insecurity, the impact of natural events, and demographic pressure. The main finding of this year’s report is the unexpected and sometimes divergent relationships between water and conflict. On the one hand, it finds that conflict death rates are 50 per cent higher in places where water stress is rising owing to heightened rainfall seasonality. On the other, it highlights how there have been no interstate wars fought over water in the modern era. In this regard, the hundreds of active freshwater treaties around the world demonstrate that strategic cooperation is effective when the downside risks are well-known , similar to nuclear non-proliferation treaties. Precipitation patterns are shi...

 There is a strong correlation between ecological threats and peacefulness. Figure 1.6 shows the correlation (r=0.58) between the GPI, which measures peacefulness at the national level, and the overall ETR score. The correlation is even higher (r=0.67) for the Safety and Security domain of the GPI. Less peaceful countries tend to have a higher prevalence of ecological threats, particularly food insecurity and water stress.  FIGURE 1.6 Ecological threat vs peacefulness There is a strong correlation between ETR and GPI scores.  The GPI comprises three domains: Safety and Security, Ongoing Conflict, and Militarisation. The prevalence of all four Ecological threats increases where countries are less peaceful in the Safety and Security and Ongoing Conflict domains. Militarisation is the only domain not strongly correlated to ecological threat. Rising ecological pressures driven by climate change carry security risks at both local and national levels. In contexts with low resil...

The map in Figure 1.1 highlights the severity of ecological threats faced by 3,125 subnational areas, with areas in red having an overall ETR score higher than 3.8 out of 5, indicating a very high level of threat. Of these subnational areas, 13.7 per cent face a very high overall level of ecological threat. These areas are home to an estimated 926 million people, or 13 per cent of the global population. By 2050, this figure is projected to rise to 1.4 billion people. There is considerable variation in levels of ecological threat both within and across regions. Europe and North America are the only two continents where no subnational areas face a high or very high level of ecological threat. Even in sub-Saharan Africa, the region with the highest overall average threat level, there are some subnational areas facing only a medium level of threat. While not all of the people in these areas will suffer from the direct impacts of adverse ecological conditions, the indirect impacts will be w...

  The ETR demographic pressure indicator is based on projected population increases between 2025 and 2050. It is a forwardlooking measure that aims to capture the ways in which rapid population growth could exacerbate existing stresses in social and natural environments . Population growth has been strongly linked to environmental degradation , particularly in areas that are already overpopulated and suffering from stretched natural resources. Of the 3,125 subnational areas assessed in the 2025 ETR, 304 have very high levels of demographic pressure , with population growth projected to exceed 50 per cent in the next 25 years. A further 337 subnational areas are facing high demographic pressure, with projected growth of around one-third . The total population in these two categories is projected to increase by more than 646 million, representing over half of the world’s population projected increase by 2050, despite comprising only around 15 per cent of the global population in 202...

  The ETR food insecurity indicator measures the likelihood that people will have sufficient food, considering availability, accessibility, affordability, and the risks posed by conflict and violence to supply chains. The indicator examines both national conditions and subnational disparities, capturing overall food supply, household purchasing power, and the effects of inequality and conflict , which disrupt markets and restrict people’s ability to obtain food. As of 2024, the ETR identifies 208 subnational areas with very high levels of food insecurity and a further 696 with high risk levels, representing nearly a third of all subnational areas. Furthermore, around three billion people currently reside in medium risk areas, making up approximately 39 per cent of the global population.   Complementing these findings, the FAO estimates that between 638 and 720 million people experienced hunger in 2024, with the largest shares in Africa and Asia. Around 28 per cent of the glob...

  Issues related to water represent the key ecological challenge facing humanity , as from them flow a host of resource scarcity concerns. The ETR’s water risk indicator is defined as the reliability of access to safe drinking water, combining two measures: the proportion of the population with access to clean water and the frequency of extreme monthly rainfall deficits compared with historical averages. This approach captures both long-term levels of water access and susceptibility to short-term fluctuations in water availability. Water stress emerges from both environmental and human factors. Ecological conditions limit water availability through factors such as insufficient rainfall, seasonal variability in rainfall, or the occurrence of floods and droughts. These factors restrict communities’ capacities to meet water demands for agriculture, households, and manufacturing industries. Human and economic pressures can also give rise to scarcity, often due to inadequate water mana...

  Between 2019 and 2024, Brazil’s Central-West region recorded some of the world’s sharpest deteriorations in overall ETR score, aggravated by exceptionally bad wildfires in 2024. The region encompasses the states of Mato Grosso, Mato Grosso do Sul, and Goiás, with Mato Grosso registering the second largest increase in ecological threat of any subnational area worldwide (after Manouba in Tunisia). Rising risks of natural events, water scarcity, and food insecurity have driven much of this deterioration. The impact of natural events was most severe in Mato Grosso, which recorded the largest deterioration nationwide since 2019. In 2024, the state experienced an exceptionally severe wildfire season , with nearly 3,900 hotspots detected in the Pantanal biome during the first half of the year – more than 16 times the number observed in the same period of 2023.6 These fires burned over 7,200 square kilometres in Mato Grosso and neighbouring Mato Grosso do Sul, the worst conditions ev...