为什么海水是咸的？

ABC，听好了。

ABC listen.

你好。

Hello.

我叫尼吉。

My name is Nij.

今天在《想象一下》这个节目里，我们要堆沙堡。

And today on Imagine This, we're building sandcastles.

我喜欢在沙子里挖坑。

I like digging holes in the sand.

对。

Yeah.

我也是。

Me too.

挖沙子挺有意思的。

Digging is fun.

对

Yeah.

捡贝壳

Collecting shells.

看起来真好看

That looks nice.

漂亮的贝壳

Pretty shells.

是的

Yeah.

我要挖一条护城河

I'm gonna add a moat.

也许再加一座吊桥

Maybe a drawbridge.

吊桥？

Drawbridge?

哦，这可真有魄力。

Oh, that's ambitious.

你可以试试看。

You can give it

不过倒是可以试试。

a crack though.

干这活儿真渴，再看看这么多水。

This is thirsty work and look at all that water.

我先去喝点水。

I'm just gonna grab a quick drink.

从海里喝？

From the ocean?

是的。

Yeah.

反正也没坏处，对吧？

Can't hurt, right?

不行。

No.

因为喝了会恶心。

Because it will make you feel sick.

喝起来像海藻加盐水。

It tastes like seaweed and salt with water.

好吃？

Yummy.

不行。

No.

尝起来是咸，但太咸了。

It tastes like salt but too salty.

但我吃饭的时候会加盐啊。

But I eat salt with my food.

对。

Yes.

为什么我不能在水里加盐喝呢？

Why can't I drink salt with my water?

那等于喝液态盐。

It's liquid salt.

有些盐对身体有害。

And some salt is bad for your body.

一点点的话

A little bit

没问题。

is fine.

那盐最初是怎么跑到水里的？

And how'd the salt get there in the first place?

乔治和雷米一直都在问这个问题。

That's what George and Remy have been wondering.

你好。

Hi.

我叫乔治。

My name is George.

我五岁了。

I'm five years old.

我叫雷米，也是五岁。

My name's Remy, and I'm five years old.

我想问的是，为什么大海是咸的？

And my question is, why is the sea salty?

为什么海洋是咸的？

Why is the ocean salty?

我做饭的时候会加盐。

I use salt when I cook.

也许有个大厨师在我们看不见的时候，往海里撒盐呢。

Maybe there's a big chef somewhere sprinkling salt in the water when we're all not looking.

对啊。

Yeah.

也许你得把店里所有的盐都买下来。

Maybe you need to buy all the salt in the shop.

拆开包装，全倒进海里。

Open the package and throw it in the ocean.

不行。

No.

也许吧。

Maybe.

不行。

No.

我们应该去问问卡塔琳娜·法布里修斯博士。

We should talk to doctor Katharina Fabricius.

卡塔琳娜是珊瑚礁专家。

Katharina is a coral reef expert.

所以戴上潜水镜，我

So grab your goggles, I

章鱼，

octopus,

然后我们就到小溪了。

then we get to the stream.

这地方简直是天堂。

This is paradise.

水清澈又湛蓝。

Water is so clear and blue.

我看到下面有海龟。

I can see turtles down there.

海星。

Starfish.

那边还有一只水母。

I can see a jellyfish right there.

等等。

Hang on.

水里那个黑色的东西是什么？

What's that black shape in the water?

它正在朝我们游过来。

It's moving towards us.

是鲨鱼。

It's a shark.

是海豹。

It's a seal.

大家好。

Hi, everyone.

是一位科学家。

It's a scientist.

吓我一跳。

Phew.

是你啊，卡塔琳娜。

It's you, Katharina.

你穿着

You're in a

潜水服。

scuba suit.

那个大氧气瓶是

That's a big tank on

背在你身后的。

your back.

那她就不会喝到海水了？

So then she doesn't get any sea water in the mouth?

对。

Yeah.

你是靠这个呼吸的？

Is that how you breathe?

是的。

Yes.

这些氧气瓶都装满了空气，所以我能在水下待很久，观察珊瑚礁。

These tanks are full of air, so I can spend a long time underwater looking at the coral reef.

你在水下能看见盐吗？

Can you see salt down there?

盐？

Salt?

是的。

Yeah.

我们想知道海水为什么是咸的。

We wanna know why the sea is salty.

盐是从珊瑚里来的吗？

Does the salt come from the coral?

不是。

No.

海洋里的盐并不是来自珊瑚，但我可以帮你找到答案。

The salt in the ocean doesn't come from the coral, but I can help you find the answer.

不过在下水之前，也许我们先在水面上玩会儿更有趣。

Before we go down on the water though, it may be more fun to start right here on the surface.

可是什么都没发生啊。

But nothing's happening.

哦，海洋里可是时刻都在发生着各种事情。

Oh, in the ocean, something is always happening.

我们来想象一下，海面上漂着一些小小的海水水滴。

Let's imagine we had tiny drops of seawater floating on the surface of the ocean.

走吧。

Let's go.

哇哦。

Woah.

好挤啊。

It's crowded.

是啊。

Oh, yeah.

每一滴海水里都充满了生命。

Every drop of seawater is teeming with life.

它们太小了，得用显微镜才能看见。

It's just so small, you need a microscope to see it.

有很多可吃的东西，还有一些海藻。

Lots of edibles and some seaweeds.

可能还有一些细小的沙粒？

Tiny little sand bits maybe?

微小的颗粒。

Particles.

它们都在四处游动。

They're all swimming around.

对。

Yeah.

海洋栖息地不只是珊瑚礁或者海带林。

Ocean habitats aren't just coral reefs or kelp forests.

每一滴水里都生活着数十亿的生物。

Every single drop of water is home to billions of creatures.

那所有的盐都去哪儿了？

So where's all the salt?

盐并不是它们的主要食物。

The salt's not the magna food.

它就在水里。

It's in here.

就算我们用显微镜看，也看不见它。

We just can't see it, even when we are microscopic.

因为盐会溶解在水里。

That's because salt dissolves in water.

只有当盐结成大颗粒，附着在食物上的时候，你才能看见。

You only see salt when it's like big salt, like it's covered in their food.

对。

Yeah.

因为它实在太小了。

Because it's really tiny.

因为它有点透明。

Because it's a bit see through.

它就消失了。

Because it gets disappeared.

一搅和就看不见了。

Gets so swish that and it can go invisible.

它溶解了。

It dissolved.

没错。

That's right.

要想看见盐，得把水去掉。

To be able to see the salt, we need to take the water out.

这办不到。

That's not possible.

得用一块超大的海绵。

It'll need a giant sponge.

然后把整个海洋的水都吸干。

And then we'll take up the whole ocean.

海洋太大了。

The ocean's too big.

水太多了。

It's too much water.

是啊。

Yeah.

这得花不少功夫。

That sounds like a lot of work.

让小水滴躺下来，看看会发生什么。

Lie back little droplets and see what happens.

这真不错。

This is lovely.

有人感觉挺舒服的。

Someone that's It feels nice.

我只是大海里的一滴水。

I'm just a drop in the ocean.

每一滴水都由数千亿甚至上万亿个水分子组成。

Every drop of water is made of billions and trillions of water molecules.

太阳出来了。

The sun's shining.

我感觉暖暖的，轻飘飘的。

I feel warm and weightless.

等等。

Hang on.

我真的没有重量了。

I really am weightless.

我在飞吗？

Am I flying?

哇哦！

Woo hoo.

我们正在上升。

We're going up.

吧吧吧吧。

Ba ba ba ba.

我们正飞向天空。

We're going up into the sky.

我们正在蒸发。

We're evaporating.

蒸发？

Evaporating?

当阳光照在海面上时，表层的水会被加热，热量让那些微小的水分子获得能量，发生转变。

When the sun shines on the ocean, the water on the surface gets warmed up, and the heat gives those tiny water molecules the energy to change.

我确实感觉有点活力充沛。

I do feel kind of energized.

水是怎么变化的呢？

How does the water change?

有些水分子在从液态变成气态时，开始彼此远离。

Some of the water molecules start to move away from each other as they change from a liquid into a gas.

就像放屁那样？

Like farts?

不是那种气体。

Not that kind of gas.

这叫水蒸气。

It's called water vapor.

就像烧开的水壶冒出来的蒸汽，温度更高的水分子会获得能量而运动。

Just like the steam coming out of a boiling kettle, the warmer molecules of water have energy to move.

蒸发就是水的小颗粒从表面脱离，升到空气里去。

Evaporation means tiny bits of water are breaking free from the surface and moving up into the air.

我们是从海洋蒸发上来的，那我们现在是咸味的水蒸气吗？

Are we salty water vapor since we've evaporated from the ocean?

我尝起来不咸。

I don't taste salty.

我尝起来不咸。

I don't taste salty.

不是的。

No.

盐比水重。

Salt is heavier than water.

它太重了，没法蒸发升到天上。

It's too heavy to evaporate and float up into the sky.

所以盐留在了海里，只有淡水蒸汽升了上去。

So salt gets left behind in the ocean, and just the fresh water vapor rises out of it.

那我们现在要去哪儿？

And where are we headed?

去云里。

The clouds.

这里的云真美啊。

The clouds are so beautiful up here.

看起来又软又蓬松。

They look nice and fluffy.

感觉像仙女的绒毛一样。

They feel like fairy fluffs.

总觉得它们是仙女的绒毛做的。

Think they are made of fairy fluffs.

可你见过哪种仙女的绒毛？

But what fairy fluffs do you know?

其实云是空气、水和 tiny 的小水滴组成的。

They're made out of air, water, tiny little raindrops.

云其实是水蒸气，但高空太冷了，那些被阳光加热的水分子失去能量，就开始重新聚拢在一起。

Clouds are made of water vapor, but it's so cold in the sky, the molecules lose all that energy they get from the sun heating them up, and they start to move back together.

咱们聚在一起，多待一会儿吧。

Let's have them together and spend more.

一个水分子真的、真的、真的特别小。

So one single molecule of water is really, really, really tiny.

但当越来越多的分子聚在一起，它们会变得越来越大，最终从气态的水蒸气变回液态的水滴。

But if more and more and more molecules get together, they get bigger until they change from the gassy water vapor back into drops of liquid water.

哎呀。

Uh-oh.

这部分我们讲过了。

We've done this part before.

水分子聚在一起就形成了雨滴。

The water molecules stick together to become raindrops.

一旦它们重到没法再留在天上时

And once they're too heavy to stay in the sky

它们就变成无雨的雨。

They're fallless rain.

在穿过空气的过程中，淡水会吸收一点点二氧化碳。

While it's moving through the air, fresh water picks up a tiny bit of carbon dioxide.

什么？

What?

二氧化碳。

Carbon dioxide.

我们吸入氧气，呼出二氧化碳。

We breathe in oxygen into our bodies and breathe out carbon dioxide.

是的。

Yeah.

没错。

Exactly.

空气中含有少量的二氧化碳。

Carbon dioxide exists in small amounts in the air.

二氧化碳是咸的吗？

Is the carbon dioxide salty?

不是。

No.

但它确实会让雨水变得有点酸。

But it does make rainwater a little bit acidic.

酸雨？

What Acid rain?

只是一点点而已。

Only a teeny tiny little bit.

我们正掉进一条河里。

We're falling in a river.

我们落在一条小溪里。

We're landing in a creek.

一只青蛙在登山杖上。

A frog in a trek pole.

嗨，小青蛙。

Hi, froggy.

还记得我说过雨水有点酸吗？

Remember how I said the rain was a little bit acidic?

是的。

Yes.

这意味着水能溶解岩石里的某些物质，比如盐分。

It means the water can dissolve some of the stuff that is inside rocks, like salt.

但这水并不咸，还是淡水。

But this water isn't salty, it's still fresh.

它不像海水那样咸。

It's not salty like seawater.

这是因为水一直在流动。

And that's because it's on the move.

淡水聚集在陆地上，形成小溪和河流，然后向下流向海洋，沿途把岩石里的那些盐分都带走了。

Fresh water collects on land, in creeks and in rivers, and then it flows downward towards the sea, carrying all those little bits of salt from the rocks as it goes.

这是冷侵蚀。

It's cold erosion.

对。

Yeah.

没错。

Exactly.

水甚至能渗入地下，从那里的岩石中也溶解出盐分。

Water can even seep underground and collect salt from rocks there too.

单靠一条河，溶解的盐量根本不足以让水变咸。

Now, the amount of salt that would dissolve into the water from one river is not enough to make the water salty.

但地球上的水非常古老。

But water on earth is incredibly old.

它已经在这整个水循环中，从海洋到云层，再到河流和地下，来回流转了数十亿年。

It's been going from the ocean to the clouds to the rivers, and underground, and back again through this water cycle for billions of years.

我们又回到了海洋。

We're back in the ocean.

现在水变咸了。

Now we're salty.

我们成了咸水。

We're salty water.

所有的盐都能遍布整个海洋。

All the salt can go everywhere, all around in the sea.

对。

Yeah.

所以当淡水流过岩石时，会带走一点点盐分，这些盐分随着溪流和河流最终全部汇入海洋。

So when fresh water washes over rocks, it picks up a tiny bit of salt, and that gets carried in streams and rivers all the way to the ocean.

因为所有微小的盐分都在不断流向海洋。

Because all the little bits of salt are moving to the ocean.

但当海水蒸发形成雨水时，盐分却留了下来，所以海水才变得咸。

But when the seawater evaporates to make more rain, the salt gets left behind, making seawater salty.

是的。

Yeah.

就是这样。

That's it.

海水之所以咸，是因为岩石。

The sea is salty because of rocks.

嘿。

Hey.

岩石还真是厉害。

Rocks really do rock.

盐一直在被输入海洋，而只有淡水被带走。

Salt is always being added to the ocean, and only the fresh water is ever taken out.

这么长时间下来，现在每升海水里大约有六茶匙的盐。

It's been happening for such a long time that now there's about six teaspoons of salt in every liter of seawater.

难怪味道这么差。

No wonder it tastes bad.

这盐可真不少。

That's a lot of salt.

我们吃的盐和海水里的是一样的吗？

Is it the same salt that we eat on our food?

是的。

Yes.

我们确实吃海盐。

We do eat sea salt.

我们现在去吃晚饭吧。

Now we're we're going going for for dinner.

晚饭。

Dinner.

在澳大利亚，我们平时吃的食盐大部分是通过蒸发海水得来的。

In Australia, most of the table salt we eat comes from evaporating seawater.

怎么做到的？

How?

方法完全一样。

In just the same way.

太阳把水加热，淡水蒸发升到天上，盐就留了下来。

The sun heats up the water, the fresh water floats up into the sky, and the salt is left behind.

然后人们把盐收集起来，装箱运到超市。

Then people come, collect it, and box it up to send it to the supermarket.

海水对我们来说不能喝，那对鱼和珊瑚来说也没问题吗？

If the salt water is bad for us to drink, is it okay for all the fish and the coral?

珊瑚能适应海水里的盐分。

Corals can handle the salt.

鱼和其他海洋生物也一样。

The fish and other sea animals too.

它们的身体结构跟我们不一样。

Their bodies are different to ours.

大多数海洋生物其实离不开盐。

Most sea animals actually need the salt.

如果放在淡水里，它们会死的。

They would die in fresh water.

我在珊瑚礁上看到的变化，是因为人类往水循环里加了东西，而不是因为盐。

The changes I see in the coral reefs are from what humans are adding to the water cycle, not the salt.

得好好保护大自然，保持环境干净。

Need to look after mother nature by keeping it clean.

我昨天从海里捡了一些塑料回来。

I took back some plastic out of the ocean yesterday.

真不错。

Lovely.

陆地上的淡水，不管是通过河流、溪水、农田，还是从水槽流走的，最终都会流入海洋，而且可能在那里停留很久。

Whatever goes into the fresh water on the land, through our rivers and streams, through our farmlands, and even down our kitchen sinks, all of it eventually makes it down to the ocean, and it can stay there for a long time.

真的吗。

Wow.

原来淡水和海水是连在一起的。

So fresh water and salt water are connected.

因为水循环嘛。

For the water cycle.

是的。

Yeah.

没错。

Exactly.

谢谢你带我们了解海洋和天空，卡塔琳娜。

Thanks for taking us into the sea and the sky, Katharina.

随时欢迎。

Anytime.

谢谢你。

Thank you.

再见。

Bye.

再见。

Bye.

乔治和雷米，当水流过岩石时，岩石里的一些盐分会溶解到水里。

So, George and Remy, when water flows over rocks, little bits of salt dissolve from the rock and mix into the water.

这叫风化作用。

That's called weathering.

这些盐分随着溪流和河流最终被带到海洋里。

The salt is carried through streams and rivers all the way to the ocean

这叫侵蚀。

It's called erosion.

盐分留在那里，因为太重了，没法再变成雨。

Where it stays because it's too heavy to become rain again.

它不会蒸发。

It can't evaporate.

这是水循环的一部分。

This is part of the water cycle.

几十亿年来，水一直从海洋升到云里，再化作雨水流进河流，渗入地下，最后又回流到海里，慢慢把越来越多的盐带进海洋，让海水变得咸咸的。

For billions of years, water has been moving from the oceans to the clouds, raining into rivers, moving underground, and washing back into the sea, slowly carrying more and more salt into the ocean and making our seas salty.

想象一下，这是ABC儿童收听频道的节目。

Imagine this is an ABC Kids Listen podcast.

想听更多播客、跟着音乐动起来，或者找些睡前故事和舒缓音轨，就去应用商店免费下载ABC儿童收听App吧。

For more podcasts to play, music to move, and stories and soundtracks for sleep, download the ABC Kids Listen app free from your app store.