美国极寒天气欢乐多：开水泼空中变雪花

What more creative way to take advantage of the coldest temperatures in decades than to conduct some homemade science experiments - including wondering at the marvel of being able to turn boiling hot water into snow.
还有什么比利用史上最极寒天气在家做些科学实验更有创造性呢？比如说把开水泼洒到空中，开水马上就神奇地变成雪花。

Unfortunately for the less scientifically minded, the experiment has become something of a health hazard if conducted in temperatures that are not quite cold enough.
不幸的是，对于那些不那么以科学态度思考问题的人来说，如果这项实验在气温不够低的地方进行，那将意味着冒生命危险。

If the pot of hot water is tossed when the temperature is too high, then instead of a magical snow shower boiling water rains down on those involved.
如果一壶开水在不足以致其结冰的温度下被泼洒出去，那么结果将不是幻妙的雪花，而是开水落在实验者身上。

Numerous people have posted pictures and comments on social media of painful injuries after their experiment has gone horribly wrong.
许多人因实验时操作不当被烫伤，网民们纷纷在社交媒体上发布和评论烫伤的照片。

Kailyn Nicole tweeted: 'I tried to throw boiling water in the air and it back fired..all the water spilled on me and now my leg is burned. Oops....'
有位叫凯琳·尼科尔的网友发推写道：“我试图将开水泼洒到空中，但它落回来了……所有的开水都洒在我身上，现在我的腿被烫伤了。哎哟……”

Hallie Benjamin added: 'So I tried to do the whole throw boiling water outside and it flew back and burned my arm so happy snow day to all.'
另一位叫哈利·本杰明的网友则表示：“告诉大家，我尝试把整壶热水洒向室外空中，然后它就洒落回来了。然后我的胳膊就烫伤了，这真是个‘欢乐’的雪天。”

One person who got it right was meteorologist Eric Holthaus. He conducted his experiment on January 6 in Viroqua, Wisconsin where the temperature was a chilly -21F with a wind chill of -51F.
气象学家埃里克的操作方法是正确的。他于1月6日在威斯康星州的韦罗奎进行了这项实验，当时气温低达华氏零下21度（约为-29℃），局部寒风地区低达华氏零下51度（约为-46℃）。

He threw his pan of hot water high into the air, being careful to make sure it blew away from him, before it turned into a beautiful, crystal cloud.
他在确保水不落回自己身上之后，把一壶开水泼到空中，随后开水就变成了漂亮如水晶般的雪云。

Boiling water turns into snow because freezing cold air holds less vapor than warmer air.
冷空气比暖空气的水蒸气含量少，所以开水会变成雪花。

When the hot water is thrown into the cold air, the air gets more water vapor than it can hold, Mark Seeley, a climatologist at the University of Minnesota told LiveScience.气候学家马克·西利告诉《生活科学》记者，当开水被泼到冷空气中时，空气中所含水蒸气就会过量。

The water vapor clings to particles, crystallizing into a snow cloud.
水蒸气粘附在颗粒上，结晶为雪云。

Mr Seeley warned not to attempt this unless the temperature had dropped to -30F or below.
西利先生警告大家，如果所在地区气温不在华氏零下30度（约为-34℃）或以下就不要尝试这一危险实验。