??heat waves are?becoming supercharged as the climate changes?– lasting longer, becoming more frequent and getting just plain hotter. one question a lot of people are asking is: “when will it get too hot for normal daily activity as we kn

ow it, even for young, healthy adults?”?the answer goes beyond the temperature you see on the thermometer. it’s also about humidity.?our?research?shows the combination of the two can?get dangerous faster?than scientists previously believed.

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跟着气候改变，热浪变得越来越强烈——其持续时刻更长、发生频率更高、温度更高。许多人都在问一个疑问：“啥时分气候会变得过于炽热，即就是对年青、安康的成年人来说，也会对往常活动构成影响？”答案跨越了你能在温度计上看到的数字。这也与湿度有关。咱们的研讨标明，两个要素联系起来可以比科学家此前认为的更简略构成风险。

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scientists and other observers have become alarmed about the increasing frequency of extreme heat paired with high humidity, measured as “wet-bulb temperature.” during the heat waves that overtook south asia in may and june 2022, jacobabad, pakistan, recorded a?maximum wet-bulb temperature?of 33.6 c (92.5 f) and?delhi topped that?– close to the theorized upper limit of human adaptability to humid heat.

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科学家和其他调查家对极点高温文高湿度（以“湿球温度”衡量）发生的频率越来越高感到震动。在2022年5月和6月热浪席卷南亚时刻，巴基斯坦雅各布巴德记载的最高湿球温度为33.6摄氏度（即92.5华氏度），印度德里甚至记载到接近人类能承受的湿热的理论上限值。

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people often point to a?study published in 2010?that estimated that a wet-bulb temperature of 35 c – equal to 95 f at 100% humidity, or 115 f at 50% humidity – would be the upper limit of safety, beyond which the human body can no longer cool itself by evaporating sweat from the surface of the body to maintain a stable body core temperature.

我们常常说到2010年宣告的一项研讨，该研讨估量，湿球温度35摄氏度（在湿度为100%等于95华氏度，在湿度为50%时等于115华氏度）将是平安上限，跨越该上限，人体将无法经过蒸腾身体表面的汗液来降温，以坚持平稳的身体中心温度。

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to answer the question of “how hot is too hot?” we brought young, healthy men and women into the?noll laboratory at penn state university?to experience heat stress in a controlled environment.?these experiments provide insight into which combinations of temperature and humidity begin to become harmful for even the healthiest humans.

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为了答复“多热才算过热”的疑问，咱们将年青安康的男性和女人带入宾夕法尼亚州立大学的noll实验室，在受控环境中研讨人体的热应热情况。这些实验研讨了哪种温度和湿度的组合将对身体完全安康的人发生损害。

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that combination of temperature and humidity whereby the person’s core temperature starts to rise is called the “critical environmental limit.” below those limits, the body is able to maintain a relatively stable core temperature over time. above those limits, core temperature rises continuously and risk of heat-related illnesses with prolonged exposures is increased.

使人体中心温度初步升高的温度和湿度的组合被称为“临界环境限值”。低于这个限值，身体可以随时刻坚持相对平稳的中心温度。翻译划线句????