According to a recent study, about half of the world’s population has experienced an additional month of extreme heat as a result of human-caused climate change.
According to the report (pdf) from World Weather Attribution, Climate Central, and the Red Cross, the extreme heat caused deaths and illnesses, damaged agricultural crops, and stretched the country’s healthcare systems.
Researchers examined weather data from May 1, 2024 through May 1, 2025 to highlight the dangers of extreme heat, which is defined as temperatures exceeding 90% of those recorded at a given location between 1991 and 2020.
According to the study, at least 30 days of extreme heat were experienced by at least 4 billion people, or 49 percent of the global population. During the same time period, 67 extreme heat events were discovered, according to the report.
Heat is arguably the deadliest extreme event, according to the report, though floods and cyclones frequently dominate headlines.
Experts claim that extreme heat-related deaths are frequently underreported or mischaracterized. One of the report’s authors, Friederike Otto, associate professor of climate science at Imperial College London, claimed that heat waves are silent killers.
People don’t pass away in a heatwave on the street; instead, they are simply not seen. Either way, they either pass away in hospitals or poorly insulated homes.
Heatwaves will affect more people, he added, with each barrel of oil burned, each tonne of carbon dioxide released, and each fraction of a degree of warming.
According to the study, the Caribbean region experienced some of the highest extreme heat days, with the island of Aruba recording 187 of them, or 142 days more than normal without climate change.
Extreme heat is most prevalent in low-income communities and vulnerable populations, including older people and those with medical conditions.
Without climate change, the report claims that the extreme heat events that took place in Central Asia in March, South Sudan in February, and the Mediterranean in July would not have been possible.
In Morocco, the temperature reached 118 degrees Fahrenheit (48 degrees Celsius) in July, which caused at least 21 fatalities.
In a statement attributed to the Red Cross Red Crescent Climate Center, Roop Singh, head of urban and attribution, claimed that people are noticing that the temperature is rising without any direct correlation with climate change.
To address the growing challenge, Singh said, “We need to quickly scale our responses to heat by better early warning systems, heat action plans, and long-term planning for heat in urban areas.”
Without eliminating fossil fuels, the researchers predicted that heatwaves would continue to grow more frequent and severe.
