The Deadly Threshold: The Unbearable Heat for Human Survival

Scientists have identified the maximum mix of heat and humidity, known as the "wet bulb temperature," that a human body can survive. At this critical limit, which occurs at 35 degrees Celsius (95 Fahrenheit) with 100 percent humidity, sweat no longer evaporates off the skin, leading to heatstroke and death. While this limit has only been breached a few times, experts warn that extreme heat events are becoming more common due to human-caused climate change. The frequency of such events has doubled over the last 40 years, and if global temperatures rise by 2.5 degrees Celsius, wet bulb temperatures will regularly exceed the survival limit. Vulnerable populations, such as children, the elderly, and outdoor workers, are at higher risk.