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We just had the first big snowstorm of the year the other day!
我们前几天刚刚迎来今年的第一场大雪！
And Squeaks and I had so much fun playing in it.
我和吱吱玩得很尽兴。
Yeah, that was when we went sledding!
对，我们滑雪玩得很开心！
We also like to build new things together when it snows, like snowballs, snowmen, or even igloos!
我们也喜欢在下雪时制作一些新东西，比如雪球、雪人和冰屋！
All of that snow is so much fun, and it can completely change the world around us.
雪非常有趣，它能完全改变我们周围的世界。
The ground is covered in a thick, white blanket, and ponds start to freeze over.
地面覆盖上厚厚的白毯子，池塘开始冻结。
And there's another thing that changes.
还有一样东西也发生了变化。
There are spikes of ice hanging down from the roof of the Fort!
沃斯堡的屋顶上垂挂着冰钉！
These long cones of ice are called icicles, which is a pretty good name for them,
这些长长的圆锥形冰被称为冰柱，名字很不错，
since they kind of look like ice turned into a popsicle!
因为它们看起来像冰变成了冰棒！
Icicles form down from different places where there's snow.
冰柱在下雪的地方形成。
You might see them growing off of roofs, gutters and even tree branches.
你可能会看到它们长在屋顶、水槽甚至树枝上。
It looks like ice is dripping right off of those trees, doesn't it?
看起来像冰正从树上往下滴，不是吗？
But how do icicles get there in the first place?
那么冰柱起初是如何形成的呢？
Well, just like a snowman, icicles are made out of the snow.
它和雪人一样，是由雪形成的。
But unlike a snowman, people don't make the icicles, they form naturally.
但与雪人不同的是，冰柱不是人为的，而是自然形成的。
For icicles to form, there have to be two things: snow, and warm sunlight.
要形成冰柱，需要两件东西：雪和温暖的阳光。
See, the snow and the ice in these icicles are made out of the same thing: frozen water.
看，冰柱里的雪和冰是由同一样物质构成的，即结冰水。
When liquid water gets really cold, like during the winter where we live, it freezes into ice.
当液态水变冷，比如我们居住的地方到冬天时，水就会变成冰。
Usually, we get our frozen water coming down from the sky as snow.
通常情况下，天上落下的结冰水是雪。
It might seem very different from the hard ice in an ice cube,
它可能看起来和冰块里的坚冰很不一样，
but the only difference is how the frozen water is shaped.
但唯一的区别是结冰水的形成方式。
Each snowflake is made up of tiny pieces of ice arranged into a snowflake shape,
每片雪花都是由雪花状的小冰块组成的，
whereas in an ice cube the little pieces of ice are all packed together.
而在冰块中，小冰块都被挤在一起。
So snow and ice are really made of the same stuff.
所以雪和冰是同一物质。
After the snow falls, it sits on the ground, on top of branches and on roofs,
下雪后，雪落在地面、树枝和屋顶上，
and as long as it's below a certain temperature, that snow will stay frozen.
只要低于一定温度，雪就会一直冰冻。
We call this temperature the freezing point.
我们称这个温度为冰点。
It's about 0 degrees Celsius or 32 degrees Fahrenheit.
冰点是零摄氏度或32华氏度。
Exactly, that's what people mean when they say it's freezing outside.
没错，这就是人们说得外面冷。
They mean it feels really cold, maybe cold enough to freeze water into ice or snow.
他们的意思是天气感觉很冷，或许冷到水冻成了冰或雪。
But even on a freezing cold day, the sun can still come out.
但是即使是在寒冷的天气里，太阳仍会出来。
And the sunlight is warm!
而且阳光很温暖！
As the warm sunlight hits the snow,
当温暖的阳光照在雪上时，
the temperature of the snow starts to slowly go above the freezing point again.
雪的温度开始再次慢慢超过冰点。
What do you think might happen to the snow, Squeaks?
吱吱，你认为雪会发生什么？
You're right, the snow will start to melt into water.
你说得对，雪开始化成水。
But it melts very slowly, and it doesn't all melt at once.
但它化得很慢，不是一次全部融化了。
The heat from the sunlight melts the top layer of snow into water, then the next, and the next.
阳光的热度将表层的雪化成水，然后再化掉下一层，再下一层。
But if it's only above freezing for a short time, something special can happen,
如果它在冰点以上停留的时间很短，就会发生特别的事，
like what happened to the snow on our roof.
就像我们屋顶上的雪那样。
As the top layer of snow on the roof melted, it rolled down the roof as liquid water,
当屋顶上的表层雪融化时，它变成液态水滚下来，
and some of it started to drip off of the roof.
有些开始从屋顶滴落下来。
But it didn't stay melted for very long!
但它融化的时间不太长！
By the time the water got to the edge of the roof,
水一到屋顶边缘，
the cold air around it cooled it back down below the freezing point.
它周围的冷空气就会使它冷却，降到冰点以下。
The water stopped in its tracks and froze back into ice,
水停下来冻成了冰，
but it wasn't shaped like a snowflake anymore.
但不再是雪花的形状。
This time, the ice was all packed together like in a hard ice cube.
这一次，冰像坚冰一样全部挤压在一起。
That tiny little frozen drop at the edge of the roof became the beginning of an icicle!
在屋顶边缘冻结的小小冰滴成了冰柱的开始！
That's true, the icicles on our roof are much bigger than one drop of ice!
没错，我们屋顶上的冰柱比那粒冰大多了！
Even though icicles start out small, they can grow.
即使冰柱开始时很小，但可以长大。
It can take a very long time for an icicle to get big, but eventually, they can get huge!
冰柱变大可能需要很长一段时间，但最终，它们会变大！
As the sun keeps melting the snow, and the cold air keeps re-freezing the water as it drips down,
太阳不断地融化着雪，冷空气一直冻结滴落的水，
the icicle will start to get longer, and thicker.
冰柱开始变大，变厚。
More ice will get added, then more and more, until you have some enormous icicles!
冰越加越多，冰柱也越来越多，直到形成巨大的冰柱！
Sometimes that takes weeks, but other times, it can happen in just a few days.
这个过程有时需要数周时间，但有时，几天就能完成。
It all depends on having the snow, the warm sun to melt it,
这一切都取决于雪，使它融化的温暖太阳
and the cold air to freeze it back into ice.
以及把它冻成冰的冷空气。
and if all these things work together just right,
如果所有这些物质协调合作，
your roof can end up perfectly decorated for the winter.
你的屋顶在冬天可以得到完美的装饰。
Have you ever seen icicles forming?
你见过冰柱形成吗？
What kinds of amazing things do you think you could build out of frozen snow or ice?
你认为你能用冰冻的冰雪制造什么神奇的东西？
Have a grown-up help you leave a comment below, or send us an email at kids@scishow.com.
找个大人帮忙在下方留言或发邮件至kids@scishow.com。
And we'll see you next time, here at the fort!
我们下期见，沃斯堡等你哦！
