we have two polar regions:

有兩塊極地

the Arctic, whose name comes from

一個是北極，名字來自於希臘文

the Greek Arktikos, of the North,

代表北方的意思

and the Antarctic

另一個是南極

from Antarktikos,

也是來自希臘文

opposite of the North.

意思是北方的相反

But there's an easier way to remember them

有一個更簡單能夠記住它們的方法

if you just remember what surrounds them.

只要你知道它們周圍是什麼就可以

The Arctic, situated in the Northern hemisphere of our planet,

北極，在地球的北半球

is an ocean entirely surrounded by land.

是一塊幾乎被陸地包圍的海洋

On the other side of the world,

在世界的另一端

the Antarctic is a continent

南極是一塊大陸

entirely surrounded by ocean.

幾乎被海洋包圍著

So, the Arctic has polar bears but no penguins,

所以北極有北極熊而沒有企鵝

and the Antarctic has penguins but no polar bears.

南極有企鵝但是沒有北極熊

Let's talk about the Arctic first.

我們先來講講北極吧

The Arctic region consists of a vast, ice-covered ocean

北極有一塊很大，被冰覆蓋著的海洋

surrounded by treeless permafrost.

四周是沒有樹木的永凍土

The area can be defined

這塊地方可以說是

as the region between the Arctic Circle

位於北極圈

and the North Pole.

以及北極之間的地方

If you were to stand at the North Pole,

如果你站在北極上

everywhere you looked, in all directions,

無論你從哪個方向看

would be south.

都是南方

But standing at the North Pole

但是站在北極上

is difficult to do for very long

你沒有辦法站太久

because it's in the middle of an ocean,

因為你是在海洋中間

covered by constantly shifting, frozen sea ice.

被不斷移動，又結冰的海冰覆蓋

If you were to fall into the water at the North Pole,

如果你掉到北極的海洋

you'd fall into water that's 13,980 feet deep.

你會落到 13,980 英尺這麼深

Above the water, average winter temperatures

水面上的冬天平均溫度

can be as low as -40 degrees Celsius,

可以低於攝氏 -40 度以下

and the coldest recorded temperature

紀錄上最冷的溫度

is approximately -68 degrees Celsius.

幾乎到了攝氏 -68 度以下

Despite these incredibly harsh conditions,

雖然這的生活環境很艱困

humans have populated areas in the Arctic

還是有人類住在北極

for thousands of years.

長達數千年了

Life in the Arctic includes organisms living in the ice,

居住在北極的其他生物還有

zooplankton and phytoplankton,

浮游動物、浮游植物

fish and marine mammals,

魚、海洋哺乳類動物

birds,

鳥類

land animals,

陸地動物

plants,

植物

and human societies.

以及人類

Okay, what about Antarctica?

好，那麼南極呢？

Antarctica is Earth's southernmost continent,

南極是地球最南方的大陸

and it contains the geographic South Pole.

它包含南極點

It's the fifth largest continent on the planet

是地球第五大的大陸

at nearly twice the size of Australia.

幾乎是澳洲的兩倍大

Almost 98% of Anarctica is covered by ice

幾乎 98% 的南極大陸被冰覆蓋

at least one mile in thickness.

厚度起碼一英里

Conditions in Antarctica are some of the most extreme

在南極的生活環境可以說是

in the entire world.

世上最極端的一種

On average, it's the coldest,

平均而言，這裡最冷

windiest,

風最大

driest continent

最乾燥

and has the highest average elevation

平均海拔最高

of all the continents.

相較於所有陸地

You might think that it snows all the time at the Poles,

你也許認為，極點一年四季都在下雪

but Antarctica is so dry,

但是南極這麼乾燥

it's considered a desert

可以說是一個沙漠

with annual precipitation

年降雨量

of only 200 millimeters along the coast

沿岸部分只有兩百毫米

and far less inland.

越往內陸越少

The temperature in Antarctica

南極的溫度

has reached -89 degrees Celsius.

可到達攝氏 -89 度以下

Because it's so harsh and hard to get to,

因為氣候太環境惡劣，也太難抵達

there are no permanent human residents on Antarctica,

所以南極上並沒有永久居住的人類

but anywhere from 1,000 to 5,000 people

只有一千到五千人左右

reside throughout the year

在南極居住一年

at the research stations scattered across the continent.

住在遍布於南極的觀測站

Even the most extreme animals fight for survival,

甚至最兇猛的動物都要為生存而戰

and only cold-adapted organisms survive there,

也只有適應寒冷的生物能夠生存

including many types of algae,

像是某些種類的水藻

animals,

哺乳類動物

bacteria,

細菌

fungi,

真菌

plants,

植物

and protista.

以及原生生物

But why is Antarctica colder than its northern cousin?

但為什麼南極比北極還要冷呢？

Well, first, much of the continent

首先，和陸地有關

is more than three kilometers above sea level,

南極陸地在海平面三公里之上

and temperature decreases with elevation.

溫度隨著海拔升高而下降

That's why mountaintops have snow on them.

這也就是為什麼山頂上會有雪

Second, remember that the Arctic

第二，還記得北極

is really a frozen ocean.

是冰凍的海洋嗎？

The water in the ocean beneath it

在冰層底下的海水

is warmer than the frozen ground in the Antarctic,

比南極的結凍大陸還要溫暖的多

and that warmth is transferred through the ice pack.

浮冰群會傳遞那種暖度

This prevents temperatures in the Arctic regions

這也讓北極的溫度不會

from reaching the extremes

到達極端

typical of the land surface of Antarctica.

像是南極的溫度一樣

Third, the seasons are conspiring against the Antarctic.

第三，季節也促成南極的冰冷氣候

During the aphelion in July,

在七月的遠日點

when the Earth is the farthest away from the Sun,

也就是地球離太陽最遠的時候

it also happens to be winter in the Antarctic,

剛好也是南極的冬天

which creates a double-whammy of cold

因此造就了這冷上加冷的

for the southern pole.

南極冰冷氣候

But despite being inhospitable,

儘管不適合人居住

the North and South Pole are a big reason

南北極是解釋現今地球樣貌 何以如此的主要原因

why our planet is the way it is.

南北極是解釋現今地球樣貌 何以如此的主要原因

Both of our polar regions

這兩塊極地

are very important climate controllers.

是控制氣候的重要因素

They help moderate the temperature

極地會舒緩

in our temperate zones

溫帶地區的溫度

and give us stable weather.

給我們穩定的天氣

As sea ice in the Arctic declines

北極的海冰下降是因為

due to climate change and global warming,

氣候變遷以及全球暖化

weather around the globe

也因此地球的天氣

becomes increasing more unstable.

變得越來越不穩定了