(单词翻译:单击)
It may be hot in the summer where you live, but here's a question: how hot is too hot?
你住的地方夏天可能很热，但问题是：多热才算太热呢？
Like, at what temperature does your body ACTUALLY start to break down? That escalated quickly.
换句话说，在多高的温度下，你的身体会开始垮掉？这个问题来得有点儿快哈。
Well, so have the world's seasonal temperatures.
随季节变化的气温也是如此。
In Death Valley, one of the hottest places on earth, the average temperature for July 2018 was a whopping 42.3 degrees C.
死亡谷，地球上最热的地方之一，2018年7月的平均气温高达42.3摄氏度。
That's the warmest single month that's ever been reliably measured in the WORLD.
这是全世界有史以来有确切记载的最热的一个月。
Seasons are getting more severe, especially summers, which are accompanied by heat waves that can be seriously deadly.
我们每个季节的温度都越来越极端了，特别是夏季，因为夏季可能还有非常致命的热浪。
In the U.S., extreme heat now causes more deaths than all other weather-related hazards.
在美国，极端的高温天气导致的死亡人数超过了其他与天气有关的死亡人数总和。
Heat waves around Europe have been killing record numbers of people, most notably since 2003,
整个欧洲地区热浪造成的死亡人数也达到了历史新高，尤其是自2003年以来，
when unprecedented summer temperatures resulted in the deaths of over 70,000 people across Europe.
夏季史无前例的高温导致整个欧洲地区的死亡人数高达7万多人。
And it shows no signs of slowing down, with all-time high temperature records being broken across the world.
而且目前还没有缓解的迹象，世界各地的高温历史记录都在被打破。
A new study is the first to project heat-related mortality into the future.
一项新的研究首次将高温导致的死亡联系到了未来。
The conclusion?
研究得出了什么结论呢？
If we don't adapt to climate change, deaths due to heat-waves will increase all over the world.
如果我们不去适应气候变化，世界各地热浪导致的死亡人数都会增加。
But how does heat actually kill you?
但高温是如何要人命的呢？
Your body normally cools itself down by transferring body heat to a cooler environment.
我们的身体通常是通过将体热传递到温度相对较低的环境来给自己降温。
We do this one of two ways: our blood vessels dilate,
这种热传递有两种途径：血管扩张，
bringing warm blood to flow close to the surface of our skin where the heat can be transferred to the air around us,
温暖的血液流到身体的表皮附近，热量经由表皮传递到人体周围的空气中，
this is why some people may appear flushed when they're hot;
这就是有些人一热就会脸红的原因；
alternatively, we lose the heat by sweating--
另外一种是通过出汗排出热量。
the liquid we release as sweat helps cool off our skin and takes some of our body heat with it as it evaporates.
体液以汗液的形式释放出去能够帮助我们的皮肤降温，在蒸发时带走我们体内的一些热量。
But our internal body temperature sits at around 37°C.
问题是，人体内部的温度维持在37°C左右。
If the air surrounding us is as warm or warmer than we are, we can't transfer our heat anywhere outside our bodies as we warm up.
如果环境的空气温度与我们人体的温度相当，甚至是高于人体的温度时，热的时候我们就无法将热量传递到周围环境。
If humidity is high AND temperatures are high,
如果湿度和温度都很高，
sweating doesn't do as good a job at cooling us off
出汗也不管用了，
because it can't evaporate--the air around us is already too full of moisture.
因为汗液无法蒸发 - 我们周围的空气水分已经饱和了。
And when these conditions occur, as they do in heat waves, it's kind of amazing how fast everything breaks down.
发生这些情况时，正如热浪来袭时那样，人体的一切机能都会迅速垮掉，速度之快，令人震惊。
If your body is starting to overheat, the first thing you may notice is that you stop sweating altogether .
当你身体的温度开始过高时，你可能先会注意到你整个人已经不再出汗了。
This means your hypothalamus, the region of your brain that controls heat regulation, has been compromised and has stopped working properly.
这就意味着你的下丘脑，即控制热量调节的大脑区域，已经受损并且停止正常工作。
You now don't have a way to give off heat, and your body temperature may be rising.
那时你就没有办法散发热量了，体温就可能上升。
You may be feeling fatigued, your brain telling your muscles to slow down, and you're at high risk of dizziness and even unconsciousness.
你可能会感到疲惫，大脑会让你的肌肉减慢工作速度，你就会面临严重的头晕甚至失去知觉的风险。
Past 41°C, your body starts to shut down in earnest.
身体温度超过41°C时，你的身体就会开始切实停止工作。
You may experience seizures or fall into a coma as your tissues stop functioning properly on a cellular and even protein level.
随着细胞甚至蛋白质层面的组织停止工作，你就可能出现痉挛或陷入昏迷的状态。
Your organs start to leak toxins into your body,
您器官内的毒素就会开始泄漏，
and if left unchecked, this process leads to multisystem organ damage, then failure, and swiftly thereafter, death.
如果不加以控制，这一过程就会导致更多器官受损，然后衰竭，之后迅速死亡。
And the thing is, temperatures don't even have to be that crazy--they just have to be significantly greater than what that area is typically used to.
问题是，环境温度无需太高 - 只需要比当地习惯的温度高出一定程度就能引发上述问题。
A 105 degree day in Arizona may not be that different from the norm, but a 90 degree day in Scotland could be deadly.
亚利桑那州105华氏度（约40.6摄氏度）的高温可能也只比平时高出一点点，但苏格兰要是哪天超过了90华氏度（32.2摄氏度）就可能热死人。
Heat waves are also magnified in urban areas,
相比乡村，城市地区的热浪问题更严重，
whose asphalt and metal buildings soak up and store more heat than surrounding areas,
因为城市里的柏油马路和金属建筑物都会吸收并储存比周围环境更多的热量，
making cities even hotter than the heat waves base temperature.
从而使得城市的温度比热浪的基础温度更高。
And the places in the world that are hotter to begin with will be hardest hit with the highest temperatures--
一开始就特别热的地方受到的影响也会更大 -
new projections estimate that by 2100, countries in South Asia may be too hot for people to survive.
新的预测估计，到2100年，南亚国家可能热到人类无法生存的地步。
So could we adapt?
那我们能适应得了吗？
New studies say probably not.
新的研究表明答案可能是否定的。
If the projected warming does take place,
如果预计的高温真的出现，
the amount of land rendered uninhabitable because it'll be too hot for the human body to handle could dwarf the amount of land lost even to sea level rise,
因为太热人体无法承受而变得无法居住的土地面积甚至会超过因为海平面上升而损失的土地面积，
another huge impending climate change concern.
而后者也是一个迫在眉睫的气候变化问题。
Just to reiterate, this means that some parts of the world will eventually be so hot that we can't live there because our bodies will actually break down.
重申一下，这将意味着世界上某些地方最终会因为温度过高导致人类无法居住，因为在那里我们的身体真的会垮掉。
Things are undeniably heating up.
无可否认，如今的气温是越来越高了。
So, how do we get our way out of this one, guys?
那么，这个问题的出路在哪里呢？
Let us know what you think in the comments below,
请在视频下面的评论中告诉我们你的想法，
and subscribe to Seeker to stay updated on the state of the world as we work to find solutions to major global problems.
还有，我们正在努力解决重大的全球问题，大家不要忘了订阅，随时了解这个世界的新变化。
Like this one here that's about a group of surfer scientists who invented a new device that monitors climate change from the surf break.
比如这个视频就讲述了一群冲浪科学家发明了一种新设备，可以一边冲着“岸边浪”一边监控冲气候变化。
Also, we have some exciting new changes coming to the channel and we can't wait to show you!
此外，我们频道即将推出一些值得期待的更新，我们已经迫不及待地想要分享给大家了！
It's gonna look a little different around here guys, but it'll be good, stay tuned.
可能看起来会有点儿不一样，但还是会很好的，请大家继续关注。
