Scientists determine the lethal heat-humidity limit for human survival.
A healthy person can’t survive over 6 hrs at 35°C (95°F) and 100% humidity. New findings suggest this threshold could be even lower due to heat’s impact on sweat evaporation.
The “wet bulb temperature” of 35°C marks this critical limit, has been surpassed only a few times in regions like South Asia and the Persian Gulf.
While wet bulb temps over 35°C haven’t caused mass mortality, stress that rising global temperatures increase the risk of such events.
Recent research forecasts wet bulb temps exceeding 35°C if the world warms by 2.5°C above pre-industrial levels.
Wet bulb measurements reveal dangerous heat levels and can help assess human endurance.
Researchers from Pennsylvania State University found that the “critical environmental limit” is reached at 30.6°C wet bulb temp, much lower than previously thought.
Vulnerable populations, including the older people, children, and outdoor workers, face higher risks during extreme heat.
Climate change’s impacts are disproportionately borne by those least able to protect themselves.
El Nino events and rising ocean surface temperatures elevate wet bulb temps, intensifying the danger.
The study underscores the urgent need to mitigate climate change’s effects to protect human lives.