Extreme heat now poses a greater threat to human life than floods, earthquakes, and hurricanes combined, according to Reinsurance News, citing a recently published report by global reinsurance company Swiss Re (Zurich, Switzerland) SONAR for 2025. In its annual report, which tracks new risks affecting insurers and global systems, extreme heat is considered a major problem not only because of its impact on health, but also on various industries and infrastructure.
According to Swiss Re, up to half a million people die each year as a result of extreme heat, which exceeds the combined death toll from other major natural disasters.
“Extreme heat used to be considered an ‘invisible danger’ because its effects are not as obvious as those of other natural disasters. Given the clear trend toward longer and hotter heat waves, it is important that we highlight the true cost to human life, our economy, infrastructure, agriculture, and healthcare systems,” said Swiss Re Group Chief Economist Jérôme Egeli, quoted in the report.
The data confirms this shift. In July 2024, for example, the three hottest days in recorded global history were observed. In the United States, heat waves have tripled in frequency since the 1960s, with each wave now lasting a whole day longer and reaching temperatures almost one degree Celsius higher.
The impact on public health is increasingly evident: approximately 480,000 deaths are recorded each year due to extreme heat. In addition, it can lead to exhaustion, heatstroke, and organ failure, as well as exacerbate chronic cardiovascular and respiratory diseases. The most vulnerable groups are the elderly and pregnant women.
Swiss Re points out that the consequences go far beyond health. In particular, heat waves combined with strong winds dramatically increase the likelihood of forest fires. For example, over the past decade, insurance losses related to forest fires worldwide have reached nearly $78.5 billion.
The report also identifies critical points of impact in key industries. For example, the telecommunications sector is vulnerable to disruptions as rising temperatures threaten the functioning of data centers and physical networks, including underground cables.
