??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 know 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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随着气候变化，热浪变得越来越猛烈——其持续时间更长、发生频率更高、温度更高。很多人都在问一个问题：“什么时候天气会变得过于炎热，即使是对年轻、健康的成年人来说，也会对日常活动造成影响？”答案超过了你能在温度计上看到的数字。这也与湿度有关。我们的研究表明，两个因素结合起来可能比科学家此前认为的更容易造成危险。
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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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科学家和其他观察家对极端高温和高湿度（以“湿球温度”衡量）发生的频率越来越高感到震惊。在2022年5月和6月热浪席卷南亚期间，巴基斯坦雅各布巴德记录的最高湿球温度为33.6摄氏度（即92.5华氏度），印度德里甚至记录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 tem
perature 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.
人们经常提到2010年发表的一项研究，该研究估计，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）将是安全上限，超过该上限，人体将无法通过蒸发身体表面的汗液来降温，以保持稳定的身体核心温度。
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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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为了回答“多热才算过热”的问题，我们将年轻健康的男性和女性带入宾夕法尼亚州立大学的noll实验室，在受控环境中研究人体的热应激情况。这些实验研究了哪种温度和湿度的组合将对身体完全健康的人产生危害。
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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.
使人体核心温度开始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，身体能够随时间保持相对稳定的核心温度。翻译划线句????
