Scientists have found the maximum combination of heat and humidity that the human body can withstand. It is known that a healthy teenager can die after six hours of heat at 35 degrees Celsius with 100% humidity. But new research suggests that this threshold may be even lower. Meanwhile, the sweating mechanism, which is the main way of cooling the body, stops and this leads to the risk of heat stroke, organ failure and death.
Known as the “wet chamber temperature”, this critical limit has been known to be exceeded only a few times, mostly in South Asia and the Persian Gulf regions. The longest trial took just two hours. Fortunately, there were no mass deaths associated with this survivability limit.
But even moderate extreme temperatures can be dangerous to humans, and it depends on age, health, and other factors. The increase in global temperature leads to more frequent cases where this limit is exceeded, which poses serious threats to health.
But experts say extreme temperatures don’t have to be near that level to kill people, and everyone has a different threshold depending on age, health, and other social and economic factors. For example, it is estimated that more than 61,000 people died from the heat last summer in Europe, where there is rarely enough humidity to create dangerous wet-bulb temperatures.
But as global temperatures rise, scientists warn that the dangerous wet bulb phenomenon will also become more common.
“Over the past 40 years, the frequency of such events has at least doubled,” said Colin Raymond of NASA’s Jet Propulsion Laboratory. He described this increase as a serious threat of climate change from human activities.
Raymond’s research predicted that if the world rose 2.5 °C above pre-industrial levels, wet-bulb temperatures would “regularly exceed” 35 °C in many parts of the world in the coming years. Scientists from the University of Pennsylvania conducted a study in which they found that the “critical environmental limit” for humans may actually be lower than previously thought. They showed that at a wet bulb temperature of 30.6 °C, problems with body thermoregulation begin to arise, which is significantly lower than the previous 35 °C.
People of different ages and health conditions respond differently to heat stress. Children and the elderly are the most vulnerable to these, as they have less ability to regulate their body temperature and sweat less. An increase in global temperature causes an increase in such events and becomes a serious threat to public health. Experts warn that climate change is already affecting people’s health, especially the most vulnerable population groups.
Source: Port Altele
