Rob Dunbar: The threat of ocean acidification

104,985 views ・ 2010-09-13

TED


请双击下面的英文字幕来播放视频。

翻译人员: Zhijun Wang 校对人员: Dian Liu
00:15
If you really want to understand
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如果你想真正了解
00:18
the problem that we're facing with the oceans,
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我们所面对的海洋问题,
00:21
you have to think about the biology
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你就必须在考虑到物理学的同时
00:23
at the same time you think about the physics.
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也考虑到生物学。
00:26
We can't solve the problems
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我们不可能解决问题,
00:28
unless we start studying the ocean
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除非我们开始用一种
00:30
in a very much more interdisciplinary way.
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跨学科的方式来研究海洋。
00:33
So I'm going to demonstrate that through
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所以我会通过对发生在海洋中的
00:35
discussion of some of the climate change things that are going on in the ocean.
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一些气候变化的讨论来阐释我的观点。
00:38
We'll look at sea level rise.
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我们会看到海平面上升。
00:40
We'll look at ocean warming.
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我们会看到海洋变暖。
00:42
And then the last thing on the list there, ocean acidification --
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那么在这张单子的最下面是,海洋酸化——
00:45
if you were to ask me, you know, "What do you worry about the most?
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如果你要问我,“你最担心发生什么?
00:48
What frightens you?"
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什么最让你害怕?”
00:50
for me, it's ocean acidification.
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对于我来说,那就是海洋酸化。
00:52
And this has come onto the stage pretty recently.
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而且这件事已迫在眉睫。
00:54
So I will spend a little time at the end.
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所以最后我会花一点时间来讲它。
00:57
I was in Copenhagen in December
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12月份我在哥本哈根
00:59
like a number of you in this room.
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就像你们一样,在这样的房间里。
01:01
And I think we all found it, simultaneously,
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然后我想我们大家都发现这是
01:04
an eye-opening
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一次令人大开眼界
01:06
and a very frustrating experience.
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同时也非常令人沮丧的经历。
01:08
I sat in this large negotiation hall,
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我坐在这样大的交流厅里,
01:11
at one point, for three or four hours,
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从某种程度上讲,大概坐了有3到4个小时,
01:13
without hearing the word "oceans" one time.
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却听不到“海洋”这个词。
01:17
It really wasn't on the radar screen.
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它确实不在讨论范围内。
01:20
The nations that brought it up
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当轮到各个国家的领导人发言时,
01:22
when we had the speeches of the national leaders --
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某个国家才把这个话题提出来。
01:24
it tended to be the leaders of the small island states,
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这好像是那些小的岛国
01:27
the low-lying island states.
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也就是那些低海拔岛国的的领导人。
01:29
And by this weird quirk
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这些低海拔的国家,
01:31
of alphabetical order of the nations,
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如基里巴斯和瑙鲁,
01:34
a lot of the low-lying states,
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因为按照字母顺序排列国家的原因,
01:36
like Kiribati and Nauru,
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他们(的领导人)坐在
01:38
they were seated at the very end of these immensely long rows.
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这些长长队伍中非常靠后的位置。
01:41
You know, they were marginalized
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大家知道,在这个交流大厅里
01:43
in the negotiation room.
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他们被边缘化了。
01:45
One of the problems
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问题之一就是
01:47
is coming up with the right target.
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选择正确的目标。
01:49
It's not clear what the target should be.
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我们还不清楚我们的目标是什么。
01:51
And how can you figure out how to fix something
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如果没有清晰的目标,
01:53
if you don't have a clear target?
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我们怎么去搞明白我们应如何解决问题?
01:55
Now, you've heard about "two degrees":
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现在,大家已经听说“2摄氏度”:
01:57
that we should limit temperature rise to no more than two degrees.
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也就是说我们不应该让气温上升超过2摄氏度。
02:00
But there's not a lot of science behind that number.
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但在这个数字的背后并没有很充分的科学道理。
02:03
We've also talked about
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我们也谈到
02:05
concentrations of carbon dioxide in the atmosphere.
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在大气层中二氧化碳的集聚浓度问题。
02:07
Should it be 450? Should it be 400?
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它应该是450ppm?或是400ppm?(注:ppm即百万分之,这里用作浓度计量单位)
02:10
There's not a lot of science behind that one either.
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在那个数字背后也没有很多的科学道理。
02:13
Most of the science that is behind these numbers,
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在这些数字背后的大多数科学道理,
02:15
these potential targets,
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这些潜在的目标,
02:17
is based on studies on land.
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依据的是陆地上的研究。
02:19
And I would say, for the people that work in the ocean
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而且我会说,对那些研究海洋
02:22
and think about what the targets should be,
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并且思索着设定什么样的目标的人来说,
02:24
we would argue that they must be much lower.
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我们会辩驳说,这些数据必须要更低。
02:26
You know, from an oceanic perspective,
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大家知道,从海洋的视角来看,
02:28
450 is way too high.
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450ppm未免太高了。
02:30
Now there's compelling evidence
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现在有非常显著的证据表明,
02:32
that it really needs to be 350.
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这个浓度应该是350ppm。
02:34
We are, right now, at 390 parts per million
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我们当前大气层里二氧化碳的浓度
02:37
of CO2 in the atmosphere.
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是390ppm。
02:39
We're not going to put the brakes on in time to stop at 450,
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我们并不打算及时踩刹车以停在450ppm,
02:42
so we've got to accept we're going to do an overshoot,
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所以我们得接受二氧化碳浓度将冲过头的事实,
02:45
and the discussion as we go forward
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并且正如我们将要进行的讨论
02:47
has to focus on how far the overshoot goes
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必须集中在这个“头”究竟过了多少,
02:50
and what's the pathway back to 350.
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我们如何能够让它降低到350。
02:53
Now, why is this so complicated?
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那么,为什么这个事情如此复杂?
02:55
Why don't we know some of these things a little bit better?
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我们为什么不能对这些事知之更深呢?
02:57
Well, the problem is that
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嗯,问题就在于
02:59
we've got very complicated forces in the climate system.
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在气候系统中存在非常复杂的动力源。
03:01
There's all kinds of natural causes of climate change.
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所有种类的自然力都能导致气候的变化。
03:04
There's air-sea interactions.
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这里有大气--海洋交互作用。
03:06
Here in Galapagos,
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就在加拉帕戈斯群岛,
03:08
we're affected by El Ninos and La Nina.
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我们被厄尔尼诺和拉尼娜现象困扰。
03:10
But the entire planet warms up when there's a big El Nino.
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但是当发生大型厄尔尼诺现象时,整个地球都会变暖。
03:13
Volcanoes eject aerosols into the atmosphere.
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火山将气溶胶喷射进大气层。
03:16
That changes our climate.
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那会改变我们的气候。
03:18
The ocean contains most of the exchangeable heat on the planet.
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海洋包含了这个星球上大部分的可交换热量。
03:21
So anything that influences
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所以,任何事情,
03:23
how ocean surface waters mix with the deep water
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只要它影响了海洋表面水层和深海水层的混合
03:26
changes the ocean of the planet.
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它就会改变海洋。
03:28
And we know the solar output's not constant through time.
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而且我们知道,随着时间的变化,太阳能的输出并不恒定。
03:31
So those are all natural causes of climate change.
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因此这些都是影响气候变化的自然因素。
03:34
And then we have the human-induced causes
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然后,我们又有了人类诱发的
03:36
of climate change as well.
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影响气候变化的因素。
03:38
We're changing the characteristics of the surface of the land,
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我们正在改变地表的某些特征,
03:40
the reflectivity.
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比如反射率。
03:42
We inject our own aerosols into the atmosphere,
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我们把自己制造的气溶胶发射到大气层里,
03:44
and we have trace gases, and not just carbon dioxide --
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我们也排放痕量(即微量)气体,不仅仅是二氧化碳——
03:47
it's methane, ozone,
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包括甲烷,臭氧,
03:49
oxides of sulfur and nitrogen.
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硫和氮氧化物。
03:51
So here's the thing. It sounds like a simple question.
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所以,这就是事实。这听起来是很简单的问题。
03:53
Is CO2 produced by man's activities
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是人类活动制造的二氧化碳
03:56
causing the planet to warm up?
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造成了全球变暖么?
03:58
But to answer that question,
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要回答这个问题,
04:00
to make a clear attribution to carbon dioxide,
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并对二氧化碳进行一个明确的归属,
04:03
you have to know something about
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你还必须了解一些
04:05
all of these other agents of change.
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造成变化的所有这些其它的媒介。
04:07
But the fact is we do know a lot about all of those things.
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不过事实上,就这些而言我们懂得够多了。
04:10
You know, thousands of scientists
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大家知道,数以千计的科学家
04:12
have been working on understanding
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致力于研究
04:14
all of these man-made causes
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所有这些人为因素
04:16
and the natural causes.
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和自然因素。
04:18
And we've got it worked out, and we can say,
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我们也已经搞明白了,并且可以说,
04:21
"Yes, CO2 is causing the planet to warm up now."
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“是的,目前二氧化碳正在导致这个星球变暖。”
04:25
Now, we have many ways to study natural variability.
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目前我们有很多办法来研究自然环境的变化。
04:28
I'll show you a few examples of this now.
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下面我将给大家展示一些案例。
04:30
This is the ship that I spent the last three months on in the Antarctic.
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这是一艘船,我近三个月来都乘着它待在南极地带。
04:33
It's a scientific drilling vessel.
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这是一艘科学钻探船。
04:36
We go out for months at a time and drill into the sea bed
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我们不时地会乘它外出几个月,到海床上
04:39
to recover sediments
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钻探,回收沉积物,
04:41
that tell us stories of climate change, right.
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就是那些能告诉我们气候变化的沉积物,是的。
04:44
Like one of the ways to understand our greenhouse future
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要了解我们的“温室未来”的方法之一
04:47
is to drill down in time
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就是及时钻探到
04:49
to the last period
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二氧化碳浓度是现在两倍
04:51
where we had CO2 double what it is today.
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的最近的那个年代。
04:53
And so that's what we've done with this ship.
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那么,这就是我们用这条船做的事情。
04:55
This was -- this is south of the Antarctic Circle.
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这曾是——这是南极圈的南面。
04:58
It looks downright tropical there.
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它看起来简直就是热带。
05:00
One day where we had calm seas and sun,
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有一天大海很平静,阳光也很温和,
05:03
which was the reason I could get off the ship.
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这也是我为什么能够下船的原因。
05:05
Most of the time it looked like this.
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大多数时间它都像这个样子。
05:07
We had a waves up to 50 ft.
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海浪高达50英尺,
05:10
and winds averaging
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大多数航程
05:12
about 40 knots for most of the voyage
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能达到40海里
05:14
and up to 70 or 80 knots.
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甚至高达70到80海里。
05:16
So that trip just ended,
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所以那趟旅行就结束了,
05:18
and I can't show you too many results from that right now,
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眼下我也不能给大家展示太多结果,
05:20
but we'll go back one more year,
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不过我们会在一年多后回来,
05:22
to another drilling expedition I've been involved in.
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到我参与的另一个钻探旅程中。
05:25
This was led by Ross Powell and Tim Naish.
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这个团队由罗斯鲍威尔和蒂姆奈什领导。
05:28
It's the ANDRILL project.
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这是ANDRILL项目。
05:30
And we made the very first bore hole
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然后我们在世界上最大的浮冰层上
05:32
through the largest floating ice shelf on the planet.
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打出了第一个钻孔。
05:34
This is a crazy thing, this big drill rig wrapped in a blanket
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这是一件疯狂的事情,这个大型钻机裹着一条毯子
05:37
to keep everybody warm,
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用来给所有人保暖,
05:39
drilling at temperatures of minus 40.
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而我们在零下40度进行钻探。
05:41
And we drilled in the Ross Sea.
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我们在罗斯海钻探过。
05:43
That's the Ross Sea Ice Shelf on the right there.
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那就是罗斯海冰架。
05:46
So, this huge floating ice shelf
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所以,这个相当于阿拉斯加大小的
05:48
the size of Alaska
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巨型浮冰层
05:50
comes from West Antarctica.
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来自于西南极洲。
05:52
Now, West Antarctica is the part of the continent
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西南极洲就是南极洲的一部分,
05:55
where the ice is grounded on sea floor
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这部分的冰层着陆在深达2000米
05:57
as much as 2,000 meters deep.
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的海床上面。
06:00
So that ice sheet is partly floating,
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因此这块冰层一部分是浮动的,
06:02
and it's exposed to the ocean, to the ocean heat.
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而且它暴露在海洋中,接受着海洋热能。
06:06
This is the part of Antarctica that we worry about.
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这就是我们所担心的那部分南极洲。
06:08
Because it's partly floating, you can imagine,
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因为它一部分是浮动的,你能够想像,
06:10
is sea level rises a little bit,
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海平面上升一点,
06:12
the ice lifts off the bed, and then it can break off and float north.
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这块冰就脱离海床了,然后它就会碎裂,飘向北方。
06:15
When that ice melts, sea level rises by six meters.
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当这块冰融化,海平面会上升6米。
06:19
So we drill back in time to see how often that's happened,
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因此我们进行“回溯”钻探,看看这种事情多久发生一次,
06:22
and exactly how fast that ice can melt.
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以及冰层融化的有多快。
06:25
Here's the cartoon on the left there.
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左边是动画。
06:28
We drilled through a hundred meters of floating ice shelf
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我们钻入了浮冰层一百米,
06:31
then through 900 meters of water
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然后通过了900米的水层,
06:33
and then 1,300 meters into the sea floor.
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然后到达1300米进入海床。
06:36
So it's the deepest geological bore hole ever drilled.
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因此这是有史以来钻探的最深的地质钻孔。
06:39
It took about 10 years to put this project together.
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营建这个工程花了大约10年左右。
06:42
And here's what we found.
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这就是我们所发现的。
06:44
Now, there's 40 scientists working on this project,
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目前有40位科学家为这个项目忙碌,
06:46
and people are doing all kinds of really complicated
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他们在开展一切真正复杂
06:48
and expensive analyses.
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而且昂贵的分析。
06:51
But it turns out, you know, the thing that told the best story
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不过大家知道,能够把事情解释得最好的
06:54
was this simple visual description.
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往往是这最简单的视觉描述。
06:56
You know, we saw this in the core samples as they came up.
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你要知道,我们在核心样本中自然而然地发现了这些。
06:59
We saw these alternations
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我们在沉积物中看到了
07:01
between sediments that look like this --
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像这样的交替出现的痕迹--
07:03
there's gravel and cobbles in there
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砾石、鹅卵石、
07:05
and a bunch of sand.
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还有一些沙子。
07:07
That's the kind of material in the deep sea.
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这就是在深海中的物质。
07:09
It can only get there if it's carried out by ice.
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这些只能被冰块带到那里。
07:12
So we know there's an ice shelf overhead.
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所以我们知道它上面有冰层。
07:14
And that alternates with a sediment that looks like this.
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然后沉积物就像这样交替出现。
07:17
This is absolutely beautiful stuff.
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这绝对是漂亮的艺术品。
07:19
This sediment is 100 percent made up
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这个沉积物百分之百是由
07:21
of the shells of microscopic plants.
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微型植物的外壳构成的。
07:24
And these plants need sunlight,
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这些植物需要阳光,
07:26
so we know when we find that sediment
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所以当我们发现这沉积物时,
07:28
there's no ice overhead.
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我们知道原来它上面本没有冰。
07:30
And we saw about 35 alternations
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我们在开放水域和冰层覆盖的水域中
07:32
between open water and ice-covered water,
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看到大约35次这些砾石和
07:35
between gravels and these plant sediments.
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植物沉积物的交替变化。
07:38
So what that means is, what it tells us
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因此这就意味着,它告诉我们
07:41
is that the Ross Sea region, this ice shelf,
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罗斯海地区,这块冰盖,
07:44
melted back and formed anew
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融化后再重生了大约
07:46
about 35 times.
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35次。
07:48
And this is in the past four million years.
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这些发生于近400万年。
07:52
This was completely unexpected.
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这完全出人意料。
07:54
Nobody imagined that the West Antarctic Ice Sheet
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没人能想象得到西南极洲冰盖
07:56
was this dynamic.
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曾经如此活跃。
07:58
In fact, the lore for many years has been,
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实际上,我们多年的认知就是,
08:01
"The ice formed many tens of millions of years ago,
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“冰层在百万甚至千万年前就形成了,
08:03
and it's been there ever since."
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它从一开始就在那里。”
08:05
And now we know that in our recent past
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现在我们知道了,在近代
08:07
it melted back and formed again,
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它融化并且重生,
08:09
and sea level went up and down, six meters at a time.
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海平面时起时落,一次落差达6米。
08:12
What caused it?
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什么原因导致其发生?
08:14
Well, we're pretty sure that it's very small changes
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呃,我们非常确信到达南极洲的太阳光量
08:16
in the amount of sunlight reaching Antarctica,
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变化非常小,
08:19
just caused by natural changes in the orbit of the Earth.
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它由地球轨道上的自然环境变化引发。
08:22
But here's the key thing:
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不过关键点是:
08:24
you know, the other thing we found out
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你要知道,我们发现了另外一件事,
08:26
is that the ice sheet passed a threshold,
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那就是这个冰盖曾经越过一道槛,
08:28
that the planet warmed up enough --
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这个星球曾暖到一定程度——
08:30
and the number's about one degree to one and a half degrees Centigrade --
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温度上升了1度到1度半——
08:32
the planet warmed up enough that it became ...
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这星球变暖到它变得。。。
08:35
that ice sheet became very dynamic
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变暖到冰层变得非常活跃
08:37
and was very easily melted.
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非常容易融化。
08:39
And you know what?
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然后你们知道么?
08:41
We've actually changed the temperature in the last century
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我们上个世纪实际的温度变化
08:43
just the right amount.
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正好是那个量。
08:45
So many of us are convinced now
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所以我们中的很多人确信
08:48
that West Antarctica, the West Antarctic Ice Sheet, is starting to melt.
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现在西南极洲,西南极洲冰盖正在开始融化。
08:51
We do expect to see a sea-level rise
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我们相信能够看到海平面上升,
08:54
on the order of one to two meters by the end of this century.
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这个世纪末将上升1到2米。
08:57
And it could be larger than that.
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而且上升幅度有可能更大。
09:00
This is a serious consequence
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对于像基里巴斯这样的国家来说,
09:02
for nations like Kiribati,
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这是非常严重的后果。
09:04
you know, where the average elevation
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你要知道,它的平均海拔
09:06
is about a little over a meter above sea level.
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只是1米多一点点。
09:08
Okay, the second story takes place here in Galapagos.
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好的,第二个故事发生在这里,加拉帕戈斯群岛。
09:11
This is a bleached coral,
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这是一块漂白的珊瑚,
09:13
coral that died during the 1982-'83 El Nino.
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一块死于1982-83年厄尔尼诺现象的珊瑚礁。
09:16
This is from Champion Island.
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这个来自冠军群岛。
09:18
It's about a meter tall Pavona clavus colony.
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这是海拔约1米高的Pavona clavus珊瑚礁。
09:21
And it's covered with algae. That's what happens.
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它已被藻类所覆盖。这就是目前所发生的。
09:24
When these things die,
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当这些生命凋谢,
09:26
immediately, organisms come in
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马上有机体会进入,
09:28
and encrust and live on that dead surface.
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并且覆盖它们,并在其表面生存。
09:31
And so, when a coral colony is killed
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那么,当一块珊瑚礁
09:33
by an El Nino event,
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被一次厄尔尼诺扼杀,
09:35
it leaves this indelible record.
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就留下了不可磨灭的印记。
09:37
You can go then and study corals
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你可以去研究珊瑚,
09:39
and figure out how often do you see this.
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搞明白这样的事情发生的有多频繁。
09:41
So one of the things thought of in the '80s
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上世纪80年代有一次(厄尔尼诺)
09:43
was to go back and take cores
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我们返回加拉帕戈斯群岛
09:45
of coral heads throughout the Galapagos
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并从那里的珊瑚礁顶采集珊瑚的核心,
09:47
and find out how often was there a devastating event.
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以便找出这样破坏性事件发生的有多频繁。
09:50
And just so you know, 1982-'83,
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正如你所知道的,1982到83年
09:53
that El Nino killed 95 percent
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那次厄尔尼诺杀死了加拉帕戈斯群岛
09:55
of all the corals here in Galapagos.
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百分之九十五的珊瑚。
09:58
Then there was similar mortality in '97-'98.
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随后,97到98年(那次厄尔尼诺)的死亡率也跟这次很接近。
10:01
And what we found
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在“回溯”钻探了400年
10:03
after drilling back in time two to 400 years
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后我们发现,
10:05
was that these were unique events.
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这些都是很独特的事件。
10:07
We saw no other mass mortality events.
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我们以前没有见过这么大规模的死亡事件。
10:10
So these events in our recent past really are unique.
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因此近年来这些事件真是非常特别。
10:13
So they're either just truly monster El Ninos,
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因此他们要么不仅仅真的是“怪兽”厄尔尼诺,
10:15
or they're just very strong El Ninos
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要么就是在全球变暖背景下发生的
10:17
that occurred against a backdrop of global warming.
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非常强大的厄尔尼诺。
10:21
Either case, it's bad news
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无论是哪种情况,对于加拉帕戈斯群岛
10:23
for the corals of the Galapagos Islands.
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的珊瑚来说都是个噩耗。
10:27
Here's how we sample the corals.
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这就是我们如何在珊瑚礁取样的。
10:29
This is actually Easter Island. Look at this monster.
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这实际上是东部群岛。看看这个怪物。
10:32
This coral is eight meters tall, right.
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这块珊瑚有8米高。
10:35
And it been growing for about 600 years.
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它已经生长了大约600年。
10:37
Now, Sylvia Earle turned me on to this exact same coral.
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现在,西尔维娅厄尔给我展示的同样是这块珊瑚。
10:40
And she was diving here with John Lauret -- I think it was 1994 --
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她与约翰劳瑞特在这里潜水——我想是1994年——
10:43
and collected a little nugget and sent it to me.
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并且采集了这个块状物并把它寄给了我。
10:45
And we started working on it,
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然后我们开始对它展开研究,
10:47
and we figured out we could tell the temperature of the ancient ocean
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我们明白我们可以通过分析这样一块珊瑚
10:49
from analyzing a coral like this.
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来得知古代海洋的温度。
10:52
So we have a diamond drill.
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我们有一个钻石钻头。
10:54
We're not killing the colony; we're taking a small core sample out of the top.
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我们没有杀死这块珊瑚礁;我们只是从它顶部采集了一个内核样本。
10:57
The core comes up as these cylindrical tubes of limestone.
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珊瑚的内核就像这些石灰石圆柱管。
11:00
And that material then we take back to the lab and analyze it.
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我们把这块材料拿回实验室并对它进行分析。
11:04
You can see some of the coral cores there on the right.
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你们可以在右边看到一些珊瑚内核。
11:07
So we've done that all over the Eastern Pacific.
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所以我们踏遍了东太平洋进行这种研究。
11:09
We're starting to do it in the Western Pacific as well.
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同样我们也正在西太平洋开展研究。
11:12
I'll take you back here to the Galapagos Islands.
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下面我们回到这里,加拉帕戈斯群岛。
11:14
And we've been working at this fascinating uplift here in Urbina Bay.
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我们一直在这个乌尔维纳湾迷人的“高地”工作。
11:17
That the place where,
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这个地方
11:19
during an earthquake in 1954,
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1954年发生过地震,
11:21
this marine terrace was lifted up
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这块海洋中的平台从海中
11:23
out of the ocean very quickly,
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抬升得很快,
11:26
and it was lifted up about six to seven meters.
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目前它已经上升了约6到7米。
11:29
And so now you can walk through a coral reef without getting wet.
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因此现在你可以不湿鞋就可以走遍整块珊瑚礁。
11:32
If you go on the ground there, it looks like this,
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如果你登上那块地面,就像这个,
11:34
and this is the grandaddy coral.
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这是一块祖父辈的珊瑚。
11:36
It's 11 meters in diameter,
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它直径有11米,
11:38
and we know that it started growing
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我们知道它从1584年
11:40
in the year 1584.
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就开始生长。
11:42
Imagine that.
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想象一下。
11:44
And that coral was growing happily in those shallow waters,
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这块珊瑚在浅海中快乐地成长,
11:47
until 1954, when the earthquake happened.
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直到1954年,发生了地震。
11:50
Now the reason we know it's 1584
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我们知道它从1584年开始生长的原因
11:52
is that these corals have growth bands.
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就是这些珊瑚拥有的生长带。
11:54
When you cut them, slice those cores in half and x-ray them,
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当你切开这些珊瑚内核,把半面切片放在X光下,
11:57
you see these light and dark bands.
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你会看到这些明和暗的带子。
11:59
Each one of those is a year.
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每一条都代表一年。
12:01
We know these corals grow about a centimeter and a half a year.
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我们知道这些珊瑚一年大约生长1.5厘米。
12:03
And we just count on down to the bottom.
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于是我们就从上数到下。
12:06
Then their other attribute is
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它们其他的属性还包括
12:08
that they have this great chemistry.
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它们拥有这样神奇的化学构成。
12:10
We can analyze the carbonate
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我们可以分析构成
12:12
that makes up the coral,
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珊瑚礁的碳酸盐,
12:14
and there's a whole bunch of things we can do.
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此外还有其他一堆事情可以做。
12:16
But in this case, we measured the different isotopes of oxygen.
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但在这个案例中,我们测量了不同的氧同位素。
12:19
Their ratio tells us the water temperature.
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它们的比例能告诉我们水温。
12:21
In this example here,
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在这个例子中,
12:23
we had monitored this reef in Galapagos
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我们用温度记录仪监测了加拉帕戈斯群岛
12:25
with temperature recorders,
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这块珊瑚礁。
12:27
so we know the temperature of the water the coral's growing in.
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所以我们就知道了珊瑚生长水域的温度。
12:30
Then after we harvest a coral, we measure this ratio,
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随后我们采集了一块珊瑚,并测量了这个比例,
12:33
and now you can see, those curves match perfectly.
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下面你就能看到,那些曲线完美吻合。
12:36
In this case, at these islands,
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在这个案例中,在这些群岛,
12:38
you know, corals
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你知道,这些珊瑚
12:40
are instrumental-quality recorders of change in the water.
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是水中温度变化的记录仪,如同机器般精准。
12:43
And of course, our thermometers
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当然,我们的温度计
12:45
only take us back 50 years or so here.
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只能让我们回溯50年左右。
12:47
The coral can take us back
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这些珊瑚却可以把我们带回
12:49
hundreds and thousands of years.
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成百上千年以前。
12:51
So, what we do:
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所以,这就是我们所做的:
12:53
we've merged a lot of different data sets.
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我们汇集了很多不同的数据集。
12:56
It's not just my group; there's maybe 30 groups worldwide doing this.
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不仅仅我们这个团队;还有全世界可能30个从事这项工作的团队。
12:59
But we get these instrumental- and near-instrumental-quality records
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我们取得这些仪器般精准或接近仪器般精准的、
13:02
of temperature change that go back hundreds of years,
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回溯了上百年的温度变化记录,
13:04
and we put them together.
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并把它们汇总起来。
13:06
Here's a synthetic diagram.
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这是一张合成图。
13:08
There's a whole family of curves here.
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这里有全套的数据曲线。
13:10
But what's happening: we're looking at the last thousand years
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发生了什么?我们看到的是这个星球近百年以来
13:13
of temperature on the planet.
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的温度变化。
13:15
And there's five or six different compilations there,
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这儿有5到6种不同的破译方式。
13:17
But each one of those compilations reflects input
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每一种方式都反映了从珊瑚上得来的
13:20
from hundreds of these kinds of records from corals.
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数百条记录的输入。
13:23
We do similar things with ice cores.
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我们对冰核也采取这样的做法。
13:26
We work with tree rings.
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我们对树木年轮也采取这样的做法。
13:28
And that's how we discover
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我们就是这样发现
13:30
what is truly natural
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什么才是真正的自然环境
13:32
and how different is the last century, right?
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以及上个世纪又是多么与众不同,对么?
13:35
And I chose this one
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我选择了这个
13:37
because it's complicated and messy looking, right.
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因为它很复杂而且很难理清楚。
13:40
This is as messy as it gets.
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就像它本身一样毫无头绪。
13:42
You can see there's some signals there.
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你可以看到那里有一些信号。
13:45
Some of the records
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某些记录显示
13:47
show lower temperatures than others.
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它们的温度要比其他的低。
13:49
Some of them show greater variability.
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某些显示了更显著的变化。
13:52
But they all tell us
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不过它们都告诉了我们
13:54
what the natural variability is.
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自然环境的变化是什么样的。
13:56
Some of them are from the northern hemisphere;
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某些是从北半球的大气层中来的;
13:58
some are from the entire globe.
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某些是从世界各地来的。
14:00
But here's what we can say:
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我能说的是:
14:02
what's natural in the last thousand years is that the planet was cooling down.
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近千年以来这个星球正在不断变冷,这才是自然的环境。
14:05
It was cooling down
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它从1900年左右就
14:07
until about 1900 or so.
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开始冷却了。
14:09
And there is natural variability
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自然环境的变化是由
14:11
caused by the Sun, caused by El Ninos.
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太阳、厄尔尼诺造成的。
14:14
A century-scale, decadal-scale variability,
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一个世纪范围内,几十年范围内的变化,
14:16
and we know the magnitude;
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我们知道这个幅度;
14:18
it's about two-tenths to four-tenths of a degree Centigrade.
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它约为五分之一到五分之二摄氏度。
14:21
But then at the very end is where
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随后,我们就到了记录的最后,
14:23
we have the instrumental record in black.
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那条记录是黑色的。
14:25
And there's the temperature up there in 2009.
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这是2009年的温度。
14:28
You know, we've warmed the globe
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你要知道,上个世纪以来,我们已经
14:30
about a degree Centigrade in the last century,
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让全球上升了约一摄氏度。
14:33
and there's nothing
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在我们的自然环境的记录中
14:35
in the natural part of that record
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从没有过这样一个时代
14:37
that resembles what we've seen in the last century.
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能够与上个世纪相提并论。
14:39
You know, that's the strength of our argument,
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你要知道,这就是我们的论据的力量,
14:41
that we are doing something that's truly different.
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也就是说,我们确实改变了一些事情。
14:45
So I'll close with a short discussion
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所以我就以一个海洋酸化
14:48
of ocean acidification.
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的简短讨论来结束(今天的演讲)。
14:51
I like it as a component of global change to talk about,
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我希望将它作为全球变化的一个组成部分来讨论,
14:54
because, even if you are a hard-bitten global warming skeptic,
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因为,即使你是一个固执的全球变暖怀疑论者,
14:58
and I talk to that community fairly often,
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(我也经常跟那种团体进行沟通)
15:00
you cannot deny
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你也不能否认
15:02
the simple physics
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二氧化碳正在被海洋
15:04
of CO2 dissolving in the ocean.
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吸收这个简单的事实。
15:07
You know, we're pumping out lots of CO2 into the atmosphere,
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你要知道,我们通过化石燃料,通过水泥的生产
15:10
from fossil fuels, from cement production.
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向大气层排放了很多二氧化碳。
15:13
Right now, about a third of that carbon dioxide
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眼下,大约三分之一的二氧化碳
15:15
is dissolving straight into the sea, right?
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直接被海洋所吸收,对么?
15:17
And as it does so,
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结果,
15:19
it makes the ocean more acidic.
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这就让海洋的酸度更强。
15:22
So, you cannot argue with that.
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所以你不必就此展开争论。
15:24
That is what's happening right now,
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那就是现在正在发生的事情,
15:26
and it's a very different issue
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它与全球变暖是非常
15:28
than the global warming issue.
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不同的两件事情。
15:30
It has many consequences.
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它会导致很多后果。
15:32
There's consequences for carbonate organisms.
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对于碳酸盐的有机体来讲有很多不良后果。
15:35
There are many organisms
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许多生物——包括植物和动物
15:37
that build their shells out of calcium carbonate --
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用碳酸钙来构筑
15:39
plants and animals both.
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它们的外壳。
15:42
The main framework material of coral reefs
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珊瑚礁的主要构筑材料
15:44
is calcium carbonate.
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也是碳酸钙。
15:46
That material is more soluble
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这种材料在酸性液体中
15:48
in acidic fluid.
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更容易溶解。
15:51
So one of the things we're seeing
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所以我们将看到的是
15:53
is organisms are having
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生物将花费
15:55
to spend more metabolic energy
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更多的代谢能量
15:57
to build and maintain their shells.
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来构筑并维持他们的外壳。
15:59
At some point, as this transience,
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在某种程度上,此刻,
16:01
as this CO2 uptake in the ocean continues,
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若海洋持续吸收二氧化碳,
16:04
that material's actually going to start to dissolve.
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那么这些物质实际上将开始溶解。
16:06
And on coral reefs,
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在珊瑚礁上面,
16:08
where some of the main framework organisms disappear,
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若那些形成主要构架的生物消失了,
16:11
we will see a major loss
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我们就会痛失
16:13
of marine biodiversity.
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海洋的生态多样性。
16:15
But it's not just the carbonate producers that are affected.
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不过不仅仅是碳酸盐制造者会受到影响。
16:18
There's many physiological processes
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还有许多生理进程
16:21
that are influenced by the acidity of the ocean.
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会受到海洋酸度的影响。
16:24
So many reactions involving enzymes and proteins
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许多酶和蛋白质参与的反应
16:27
are sensitive to the acid content of the ocean.
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对海洋的酸度非常敏感。
16:30
So, all of these things --
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因此,所有这些——
16:32
greater metabolic demands,
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更旺盛的代谢需求,
16:34
reduced reproductive success,
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降低的繁殖成功率,
16:36
changes in respiration and metabolism.
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呼吸作用和代谢过程的变化。
16:39
You know, these are things that we have good physiological reasons
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你要知道,在受到目前片刻的影响后,
16:42
to expect to see stressed
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我们能找到足够充分的生理原因
16:44
caused by this transience.
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来预测到这些变化。
16:46
So we figured out some pretty interesting ways
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因此我们发现了一些非常有趣的方法
16:48
to track CO2 levels in the atmosphere,
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来跟踪数百万年前大气层中
16:51
going back millions of years.
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的二氧化碳水平。
16:53
We used to do it just with ice cores,
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我们过去仅仅使用冰核,
16:55
but in this case, we're going back 20 million years.
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但是在这个案例中,我们要回溯2000万年。
16:58
And we take samples of the sediment,
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于是我们就采集了海底沉积物的样本,
17:00
and it tells us the CO2 level of the ocean,
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它告诉我们海洋中二氧化碳的浓度
17:03
and therefore the CO2 level of the atmosphere.
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从而我们也知道了大气中二氧化碳的浓度。
17:05
And here's the thing:
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接下来的事情就是
17:07
you have to go back about 15 million years
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我们必须回溯大概1500万年
17:09
to find a time when CO2 levels
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去寻找一个二氧化碳浓度跟
17:12
were about what they are today.
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今天相近的年代。
17:14
You have to go back about 30 million years
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我们必须回溯大约3000万年
17:16
to find a time when CO2 levels
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去寻找一个二氧化碳浓度相当于
17:18
were double what they are today.
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今天的两倍的年代。
17:20
Now, what that means is
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现在,这意味着
17:22
that all of the organisms that live in the sea
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所有生活在海洋中的生物都
17:24
have evolved in this chemostatted ocean,
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在这个恒定的海洋中进化,
17:27
with CO2 levels lower than they are today.
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而其中的二氧化碳浓度低于现在的浓度。
17:30
That's the reason that they're not able to respond or adapt
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这也是他们为什么没有能力去应对或适应
17:33
to this rapid acidification
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海洋的快速酸化。
17:36
that's going on right now.
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目前这正在发生。
17:38
So, Charlie Veron
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所以,查理弗隆
17:40
came up with this statement last year:
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去年带着这个课题来到这里。
17:42
"The prospect of ocean acidification
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“海洋酸化的前景
17:44
may well be the most serious
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可能是目前人类活动造成的
17:46
of all of the predicted outcomes
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二氧化碳排放所导致的所有可预见的
17:48
of anthropogenic CO2 release."
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后果中最严重的一种。”
17:51
And I think that may very well be true,
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我认为他说的很靠谱,
17:54
so I'll close with this.
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所以我会一直密切关注它。
17:56
You know, we do need the protected areas, absolutely,
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你要知道,我们绝对需要一些受保护的领域,
17:59
but for the sake of the oceans,
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但是看在海洋的份上,
18:01
we have to cap or limit CO2 emissions
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我们必须马上限制
18:03
as soon as possible.
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二氧化碳的排放。
18:05
Thank you very much.
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非常感谢!
18:07
(Applause)
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(掌声)
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