We remain mostly water for the rest of our lives.

在我們這一生中，我們身體的水份也大多維持這個比例

We cannot survive even a week without fresh water.

我們無法在缺水一週的狀況下存活。

There's no life without it

任何生命皆以賴著水

for ecosystems,

對生態系統、

societies,

社會、

and individuals.

以至於個人皆是如此。

So, how much usable water is there on Earth?

所以，地球上到底有多少可利用的水呢？

Most of the water on Earth is ocean,

地球上大部份的水存在於海洋，

a salty 97.5%, to be precise,

精確來說：97.5％的鹹水

and the remaining 2.5% is fresh water.

和其餘2.5％的淡水

That little sliver of liquid sustains human life on Earth,

這珍貴的液體使得人類可以在地球上存活，

it literally holds up civilizations.

並撐起我們的文明。

2.5% is a small proportion to be sure,

2.5％雖然已經是很小的一部份了，

and even that is broken down into smaller parts:

但是還是可以在被劃分成更小的部份：

surface water,

地表水、

water in ice caps and polar regions,

存在於冰帽和極區的水、

and ground water.

及地下水。

First, surface water.

首先，讓我們談談地表水。

All the liquid water above ground is surface water

所有在地表上的液態水都是地表水

and it is a tiny blip of an amount.

但這僅占所有水資源的一小部份。

0.3% of all fresh water is surface water.

0.3%的淡水是地表水。

It may seem counterintuitive,

這或許和我們想像的不同，

but it accounts for little streams all over the planet.

不過這已包含地球上所有的溪流。

All rivers, including the Nile, the Jordan, and the Mississippi,

所有的河流，包含尼羅河、約旦河和密西西比河，

and lakes, large to small,

以及大大小小的湖泊：

like Victoria, the Great Lakes, and Baikal.

像是維多利亞湖、五大湖和貝加爾湖。

Second, ice caps and polar regions

再者，冰帽和極區

freeze up to 70% of the planet's fresh water.

冰封了地球上70%的淡水

This water is significant,

這佔了所有水資源中的很大部份，

but it isn't available for human use in a regular way.

但卻無法透過常規的方式供人類使用。

Finally, nearly 30% of all water on Earth is ground water.

最後，地球上將近30%的水是地下水。

As the name suggests, that's water in the ground.

就如同名字所示，這部份的水是存在地底下。

It can rest still and deep in huge caverns,

它可能是靜止地存在巨大洞穴的深處，

or it can snuggle in the little crevices of rock and pebble.

也可能是潛藏岩石裂隙和卵石的縫隙之間。

The upshot - thank goodness for ground water!

總歸一句話：感謝上天給我們地下水。

It's invisible to us,

雖然我們看不見地下水，

but it is much more plentiful than surface water.

但它比地表水更為豐沛。

It is much more reliable

地下水也比凍結的水體更可靠

and easier to obtain than frozen water.

也更容易取得。

Without ground water, our societies would be parched.

如果沒有地下水，我們的社會將會枯萎。

So, how are we using that water?

那我們又是如何運用水資源呢？

As a result of industrialization and population growth,

因為工業化和人口成長，

demand for fresh water skyrocketed in the last century.

自上世紀起我們對於淡水的需求暴增。

Where is all that water going?

而這些水又被用在哪些地方呢？

First, we have to remember

首先，我們必須瞭解

that fresh water is a global concern,

淡水雖攸關整個世界

but it is always local.

但永遠具區域性。

Context matters.

也就是說

The Sahara is not Seattle.

薩哈拉並非西雅圖

Still, some general information can help us

仍然有些概念可以幫助我們

get a handle on major trends.

理解整體趨勢。

Who consumes the most fresh water?

誰消耗了大部份的淡水？

And, what sectors consume the most fresh water?

以及，那些區域使用最多的淡水

First, who.

我們先說說是誰。

Well, the United States consumes the most water

嗯，美國使用了最多的水資源

per capita of any country in the entire world,

也就是說超過世界上的任何國家，

followed by parts of Europe

緊接著是部份的歐洲國家

and large industrializing nations like China.

和諸如中國等高度工業化的國家

But, this doesn't tell us what water is being used for.

但是這並不能告訴我們水被運用在那些方面。

So let's look at it another way.

所以就讓我們換種角度吧！

If we ask what kinds of uses water is going towards,

如果我們探討水的用途，

we see a different picture.

我們將會看到不同的結果。

Agriculture accounts for roughly 70% of global fresh water consumption.

農業用水大約佔全世界水資源消耗的70%。

Again, remember the numbers vary by region,

雖說數據會因地區而不同，

but still, it's a staggering amount.

但這仍是個驚人的用量。

And, this makes a certain kind of sense:

然而，這也很合理：

we need to eat,

我們需要食物，

we need water to grow food;

所以我們需要用水來種植；

the bigger the population,

人口越多，

the more food we need;

我們所須要的食物也越多；

and, the wealthier we get,

而且，我們越富有，

the more meat we eat,

我們就會食用更多肉類食品，

and the more water is required to produce our food.

導致我們需要將更多的水用在生產食物。

Furthermore, 22% of all fresh water worldwide

再者，世界上22%的淡水

goes to industrial uses.

用在工業生產。

This includes the production of electricity,

這也包含生產電力，

the extraction of fossil fuels,

提煉石化燃料，

and the manufacturing of all manner of goods,

和生產各式產品。

from microchips,

從晶片，

to paper,

到紙張，

to blimps.

到飛船。

70% to agriculture,

70%用在農業，

22% to industrial uses,

22%用在工業，

what's left?

其餘的呢？

8%

8%

All those domestic uses -

皆用於家庭生活。

cooking,

煮飯、

cleaning,

清潔、

bathing,

洗澡、

drinking

飲用

- it's a drop in the bucket of overall water use.

這都包含在所有水份消耗的一部份。