冰冻星球（2011）

caused fury among the competing countries
而这样的争端将会源源不断
and it's unlikely to be the last such dispute.
北极从来没有这么重要过
The Arctic has never been so important
而这并不仅仅因为它资源丰富
and not just because of its resources.
西北水道
The North-West passage,
是加拿大北部和阿♥拉♥斯加周围的
a legendary sea route
一条传奇海路航线
around the north of Canada and Alaska,
2007年夏天
cleared of ice in the summer of 2007
自有记录以来 冰雪首次消融
for the first time since records began.
从此 往来大西洋和太平洋的航线
This promises a much faster and cheaper shipping route
变得既快捷又便宜
between the Atlantic and Pacific Oceans.
无冰的北冰洋同时也惠及了一些野生动物
And some wildlife could benefit from an ice-free Arctic too.
北极露脊鲸是少数
Bowhead whales are one of just
一整年待在北极的一种鲸鱼
a few whales that can live year-round in the Arctic
因为它们没有背鳍
because they have no dorsal fin.
因此它们能在狭小的空间里浮起来呼吸
This means they can come up for air in small spaces
并能在冰下自如游弋
and travel easily under the ice.
独特的身形曾让它们
Their unique body shape used to mean that the Arctic whales had
几乎整年都独占这片海域
the seas to themselves for most of the year.
但现在 南方的"亲戚"也来搬来这里
But now, some cousins from down south are moving in.
现在在北极也常常可以见到虎鲸了
Killer whales are now a much more common sight in the Arctic.
长长的鳍虽阻碍了它们在冰下穿梭
Their tall fins make it difficult for them to travel under ice,
但更长的夏天使它们能去到更北的地方
but the longer summers mean they can travel much further north
充分利用北极海洋里丰富的资源
and make the most of the rich Arctic seas.
在变幻莫测的北极
For animals and people,
对动物和人来说
it will be those that can adapt
只有适者才能生存
who will thrive in a changing Arctic.
冰雪融化不单纯是北极的问题
But the loss of sea ice isn't just an issue for the Arctic,
因为冰雪的状态影响了整个地球的气候
because the state of the ice affects the climate of the whole planet.
冰雪是白色的
Because it's white,
它能将90%的太阳能量反射回去
the ice reflects up to 90% of the Sun's energy.
这叫做反射效应
This is called the albedo effect
这就是为什么在北极
and it's why we often see heat haze in the Arctic,
即使很冷 也能看到热霾
even when the air feels cold.
冰冻的北冰洋就像一块巨大的反射镜
The frozen Arctic Ocean acts as a huge reflector,
将太阳的热量反射回去
bouncing back the Sun's heat into space.
自古以来 这能帮助地球降温
Throughout history, that has helped to cool the planet,
一旦冰雪融化就将是另外一番景象了
but when the ice melts, it's a different story.
因为海水是深色的
Because sea water is dark,
它吸收了大部分太阳的热量
it absorbs most of the Sun's heat.
在北极 这会触发连锁反应
In the Arctic, this can trigger a chain reaction,
更多的冰雪被渐暖的海水融化了
as the warming water melts more ice,
变成了更多的海水 吸收太阳的热量
exposing more water to the Sun's heat.
广阔的区域并不反射而是吸收热量
This cycle of warming, as huge areas start to absorb rather than
因而 和北美面♥积♥一样大的北极区域
reflect heat, is the main reason why the Arctic,
变暖速度是地球其他地方的两倍
a region the size of North America,
而这个热循环就是罪魁祸首
is warming twice as fast as the rest of the Earth.
正在融化的冰雪是个大问题
So, melting sea ice is a big issue.
但还有另外一种冰雪可能会对我们的世界
But there's another kind of ice that could have an even more
造成更深刻的影响
dramatic impact on our world.
那就是在陆地上的冰川
The ice that is found on land.
这是淡水冰
This is fresh water ice,
是由过去数千年里不断的降雪积累而成的
formed from thousands of years of accumulated snowfall.
不管你信不信
This is the front of a glacier,
这是一块非常小冰川的正面
quite a small one, believe it or not.
冰川就像是冰冻的淡水河
Glaciers are like rivers of frozen fresh water
在陆地上纵横交错
flowing across the surface of the land.
像大多数两极冰川一样 这块冰川
This one, like most polar glaciers,
正从一块巨大的内陆冰原上缓缓流下
is flowing down from a vast inland ice sheet.
在这些冰原上发生的变化
And it's what happens to those ice sheets
会彻底改变地球的面貌
that could radically alter the face of the planet.
格林兰冰原是目前北极最大的冰原
The Greenland ice sheet is by far the largest in the Arctic.
有些地方有两英里厚
It's two miles thick in places
面♥积♥是英国面♥积♥的六倍
and six times the size of the United Kingdom.
每年夏天 一些冰原表面融化
Every summer, some of the surface of the ice sheet melts,
形成了蔚蓝色的湖水
forming sapphire blue lakes of melt water.
由于格林兰变暖 在过去的二十年里
More and more of these lakes have been forming
形成了越来越多的这种湖
as Greenland has warmed over the last 20 years.
只需几周便可形成这样的湖
This lake has grown over several weeks
湖水向外溢出
and now it's overflowing,
在冰原上开拓出了一条水道
carving a deep channel through the ice.
这些水道在冰原上纵横交错
A network of channels criss-crosses the ice sheet,
但很多突然就流到了尽头
but many of them come to an abrupt end.
像这样巨大的洞穴会突然出现
Huge holes, like this, can open up quite suddenly,
让融化的淡水流走
draining the melt water away.
这些瀑布叫做冰川锅穴
Alun Hubbard is a glaciologist,
冰河学家艾伦·哈伯德
studying the enormous power
研究的便是它们的巨大能量
of these waterfalls, which are known as moulins.
今天我们找到了这个非凡的冰川锅穴
We've got this amazing moulin going off here today.
从湖里溢出来的水正在慢慢流干
The water's overflowing from the lake, which is beginning to drain.
无数吨♥的水从这里倾泻而下
Tonnes of water cas cading down this pipe that is, effectively,
相当于是从一千米高的冰川上
plummeting to the depths of the ice sheet through
骤然跌落至冰原最深处
over a kilometre of vertical ice.
艾伦来这里是为了研究这些水流去了哪里
Alun is here to study where the melt water goes
以及剩下的冰川会受到什么影响
and what effect it has on the remaining ice.
为此
To do that,
他要找到一个刚流干的冰川锅穴
he needs to find a moulin that has recently run dry.
仅一个星期前 这里有一个
Just a week ago, there was
三英里长 十米深的湖
a three-mile long, ten-metre deep lake here.
这些水的重量把下面的冰都压碎了
The weight of all that water cracked the ice beneath
湖水倾泻而出
and the lake drained in just a few hours
几小时内就流干了
with incredible force.
千吨♥的冰漂石像骰子一样被扔了出去
Thousand-tonne ice boulders were tossed about like dice.
艾伦的团队已经找到了让湖水消失的洞穴
Alun's team have found the hole down which the lake disappeared
他们想要来个近距离观察
and they want to have a closer look.
这对恐高的人来说是绝不可能的
It's not a job for anyone with a fear of heights.
可以看到这里已经干涸
As you can see, it's dry up here,
但如果仔细听
but if you listen,
便能听到大量的流水
you can hear the thunder of,
从深处贯入其中的隆隆声
there's a lot of water entering it at some depth.
艾伦想在冰川锅穴深处安装一个传感器
Alun wants to place a sensor deep into the moulin
来研究有多少水在冰川里穿梭
to discover how much water is flowing through the ice.
向下深入的时候 他们仿佛回到了从前
As they drop, they travel back in time.
三十米深处的冰是一万年前
30 metres down and they reach ice formed from snow that fell
冰河世纪时期的降雪堆积起来的
10,000 years ago, in the last Ice Age.
一旦湖水干涸 就像打开了阀门
When this lake drained and the plug got pulled
整个水流都会从这冲刷而下
and the whole lot flushed down through here,
这块冰原就会增高一米
this ice sheet, it rose by a metre
因为水流到了冰床之下
as that water accessed the bed and forced,
迫使冰原提升
jacked up the ice sheet.
我们知道
So, we know that the water
水在这整个垂直坠落过程中
in this whole plumbing cavity system, down here,
径直冲破了冰川
we know that shoots straight through that ice
直接撞击了冰原的底部
and actually hits the bed of the ice sheet.
我们到水边了 我能看到水了
We've hit the water, I can see the water now.
很棒 干得漂亮
Great. Nice work.
这项大胆的试验旨在探究
This daring experiment is measuring how the water flowing
在冰原底下 水的流动是怎样影响
under the ice sheet affects the speed with which the glaciers
冰川流向大海的速度
flow from it, down to the sea.
原理是 水起到了润滑的作用
The theory is that the water is acting as a lubricant.
所以水越多 冰川移♥动♥的速度就更快
So, the more water there is, the faster the glacier flows.
肉眼看来冰川好像岿然不动
To the naked eye, glaciers don't appear to move at all.
但它确实在移♥动♥
But move, they do.
这些快速回放镜头是近四年来
These unique time-lapse images
捕捉到的画面
were captured over the last four years.
通过长时间的观察 我们得知
Through long observations, we now know
格陵兰冰川向大海移♥动♥的速度
that Greenland's ice is flowing down to the sea
是二十年前的两倍
twice as quickly as it was 20 years ago.
冰川的速度影响着我们的海平面高度
The speed of the glaciers affects our sea levels
因为当它们遇到了水域
because when they reach the water,
它们就破碎成冰山