一项新的研究预测，在未来20年或更长时间里，美国主要人口中心将经历最极端的温度提升。
Some parts of the United States could experience up to 30 times more extreme heat than scientists had predicted, the study found.
研究发现，美国某些地区的极端高温可能比科学家曾经预测的高出30倍。
The study was a project of researchers at Arizona State University. Their findings were reported in Proceedings of the National Academy of Sciences.
这项研究是亚利桑那州立大学研究人员的一个项目。他们的研究结果发表在《美国国家科学院院刊》上。
The researchers made predictions for extreme heat and cold exposure in 47 major U.S. cities.
研究人员对美国47个主要城市的极端高温和低温暴露进行了预测。
To break down the local effects of rising temperatures worldwide, the research team measured the effects of heat in "person-hours." This was defined as a human being exposed to extreme heat for one hour.
为了打破全球温度上升的地方影响，研究人员以“人/小时”的方式测量了温度的影响。它被定义为一个人在高温下暴露一小时。
The researchers considered three areas. The first was local definitions of what an "extreme" temperature is. Another was how city environments change the effects of extreme heat. The researchers also studied the effects of population migration and growth.
研究人员考虑了三个方面。首先是极端高温的地方定义。其次是城市环境如何改变极端高温的影响。研究人员还研究了人口迁移和增长的影响。
They also considered local standards for extreme heat. This is important because an intensely hot day in places like Phoenix, Arizona, or Austin, Texas, may not feel extreme to locals in those cities. However, the same heat in New York City could result in deaths - especially among higher risk groups, like older adults or the homeless.
他们还考虑了极端高温的地方标准。这很重要，因为在亚利桑那州凤凰城或得克萨斯州奥斯丁市这些地方的酷热天气，可能对这些城市的当地人来说不算极端高温。然而，同样的温度在纽约市可能会导致死亡，尤其是在老年人或无家可归者等高风险人群中。
With that in mind, the researchers came up with two areas of study: absolute increases and relative increases in extreme heat.
考虑到这点，研究人员提出了两个研究领域：极端高温的绝对提升和相对提升。
The top three cities for absolute increases in people affected by extreme heat were New York, Los Angeles, and Washington D.C.
人们受极端高温绝对提升影响的前三大城市是纽约、洛杉矶和华盛顿。
Relative increases were predicted by combining temperature factors with information on population growth.
相对提升是结合了温度因素和人口增长信息来做出预测。
The researchers predicted that the most intense relative increases would be in the Florida cities of Orlando and Miami, as well as Austin, Texas. They added that because these cities are growing quickly, more people there will be exposed to extreme heat.
研究人员预测，相对提升最快的是佛罗里达州奥兰多市、迈阿密市，以及得克萨斯州奥斯丁市。他们还说，由于这些城市发展迅速，当地人将遭受极端高温。
The southern city of Atlanta, Georgia, made both lists.
乔治亚州亚特兰大市这个南方城市同时入选了这两个名单。
The researchers said the study shows that cities should prepare at the local level to avoid serious disorders and death resulting from extreme heat. They expressed support for safety measures such as having cooling centers and water available. They also noted the importance of having dependable sources of energy, since extreme heat can lead to power outages.
研究人员表示，这项研究表明城市应该在地方一级做好准备，以避免极端高温导致严重疾病和死亡。他们表示支持出台相关安全措施，例如提供降温中心和水源。他们还指出了拥有可靠能源的重要性，因为极端高温会导致停电。
I'm Bryan Lynn.
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