曾经有一个世界 Once there was a world
它与我们的星球没什么不同 not so very different from our own.
偶尔会有些自然灾害或者是大规模的火山爆发 There were occasional natural catastrophes, massive volcanic eruptions
时不时还会有小行星降临在星球上砸几个坑 and, every once in a while, an asteroid would come barreling out of the blue to do some damage.
可在最初的100万年里 But for the first billion years or so,
它很像是一个天堂 it would've seemed like a paradise.
这大概就是金星在太阳系还年轻时的样子 This is what we think the planet Venus might have looked like when our solar system was young.
然后 一切就开始变得糟糕了 Then things started to go horribly wrong.
中文翻译 幸福的微笑 timhal
蓝光版字幕制作 timhal@HDWinG字幕组
原字幕取自射手 由HDWinG字幕组修正 请勿去掉制作者信息
《宇宙：时空之旅》 第十二集
金星或许曾是一个天堂 The planet Venus, which once may have seemed like a heaven,
但现在却是一个地狱 turned into a kind of hell.
造成这个差异的原因是因为有一些微妙的自然平衡被打破了 The difference between the two can be a delicate balance,
而且是比你想像中更为微妙的关系 far more delicate than you might imagine.
这个平衡一旦被打破 就再也无法挽回 Once things began to unravel, there was no way back.
这就是金星 This is what Venus,
距离我们最近的行星 今天看上去的样子 our nearest planetary neighbor, looks like today.
金星上的海洋已经消失很久了 Venus's oceans are long gone.
星球的表面现在比烧烤炉还要烫 The surface is hotter than a broiling oven,
热得足以融化铅 hot enough to melt lead.
为什么呢 Why?
你也许认为这是因为金星到太阳的距离要比地球少30% You might think it's because Venus is 30% closer to the Sun than the Earth is,
但这不是真正的原因 but that's not the reason.
金星现在完全被硫酸云覆盖着 Venus is completely covered by clouds of sulfuric acid
几乎没有阳光可以照射到它的表面 that keep almost all the sunlight from reaching the surface.
按理来说这应该让金星比地球更寒冷 That ought to make Venus much colder than the Earth.
但为何金星会如此的灼热？ So why is Venus scorching hot?
那是因为有小部分的阳光 It's because the small amount of sunlight
穿过云层抵达了地面 that trickles in through the clouds to reach the surface
却没能反射回去 can't get back out again.
能量不能散发是由于浓密的大气阻隔 The flow of energy is blocked by a dense atmosphere
那就是二氧化碳 of carbon dioxide.
二氧化碳简称CO2 That carbon dioxide gas-- or CO2 for short--
它就像毯子一样阻止热量的散发 acts like a smothering blanket to keep the heat in.
没人在金星上烧煤 No one is burning coal
或是开着大马力的汽车在上面逛 or driving big gas-guzzlers on Venus.
自然能灭掉环境的平衡 Nature can destroy an environment
而不需要借助人的力量 without any help from intelligent life.
金星现在正处于强烈的温室效应中 Venus is in the grip of a runaway greenhouse effect.
为什么我们现在像是在一个碗里？ Why does it look like we're inside a bowl?
那是因为浓密的大气压力 It's due to the intense atmospheric pressure.
这是金星13号的残骸 That's the wreck of Venera 13.
1982年 In 1982, the scientists and engineers
苏联的科学家与工程师们 of what was then the Soviet Union
成功地将这艘探测器送到了金星 successfully landed this spacecraft on Venus.
他们设法让飞船 They managed to keep it refrigerated
保持了2个小时以上的冷冻状态 for overtwo hours,
让它能给四周拍照 so it could photograph its surroundings...
并将照片传回了地球 and transmit the images back to Earth
随后飞船上的电子设备就烧毁了 before the on-board electronics were fried.
金星与地球在诞生初期具有相同的 Venus and Earth started out with about the same amount
碳含量 但两个星球却被推上了 of carbon, but the two worlds were propelled
截然不同的发展道路 along radically different paths,
碳元素在其中起到了决定性的作用 and carbon was the decisive element in both stories.
在金星 几乎所有的大气 On Venus, it's almost all in the form of gas--
都由二氧化碳组成 carbon dioxide-- in the atmosphere.
地球上大部分的碳已经在久远的年代中 Most of the carbon on Earth has been stored for eons
以碳酸盐岩的形式被储存起来 in solid vaults of carbonate rock,
就像这一块 它就是其中一种形式 like this one, part of a chain that forms
这就是著名的多佛海岸白色悬崖 the celebrated White Cliffs of Dover,
它位于英吉利海峡的边上 right on the English Channel.
是哪位巨人修建了这样的世界奇观？ What titan built this wonder of the world?
那是一种比针头还要小1000倍的生物 A creature a thousand times smaller than a pinhead.
数以万亿计 Trillions of them.
它叫单细胞藻类 One-celled algae.
火山将二氧化碳送入大气后 Volcanoes supply carbon dioxide to the atmosphere,
海洋将它缓慢地吸收 and the oceans slowly absorb it.
这个过程要延续好几百万年 Working over the course of millions of years,
先是微小的藻类吸收了二氧化碳 the microscopic algae harvested the carbon dioxide
并将它转化为这些小贝壳 and turned it into these tiny shells.
日积月累 最终沉积为白垩 They accumulated in thick deposits of chalk,
我们也称之为石灰岩 它积聚在海床上 or limestone, on the ocean floor.
最终 永不停息的地壳运动将海床推起 Later, the restless Earth pushed up the sea floor
将它塑造成这些巨大的悬崖 and carved out these massive cliffs.
其他的海洋生物 Other marine creatures
用二氧化碳建造了巨大的珊瑚礁 took in carbon dioxide to build enormous coral reefs.
海洋也可以把溶解的二氧化碳转换为石灰岩 And the oceans converted dissolved CO2 into limestone
而不需要生物的帮助 even without any help from life.
最终 只有微量的二氧化碳气体 As a result, only a trace amount was left as a gas
留在了地球的大气中 in Earth's atmosphere.
还不到每百分之一中的三百分之一 Not even three-hundredths of one percent.
相当于每1万个分子中 Think of it-- fewer than three molecules
只有不到3个分子保留下来 out of every ten thousand.
而这几个分子就是最关键的因素 And yet, it makes the critical difference
决定了地球是生命的乐土还是荒芜之地 between a barren wasteland and a garden of life on Earth.
要是一点二氧化碳都没有 With no CO2 at all,
地球将会被冰冻 the Earth would be frozen.
可要是二氧化碳的数量再多一倍 And with twice as many,
也就是像前面所说的 每1万个分子中 we're still talking about only six molecules
有6个分子保留下来 out of ten thousand.
令人不安的炎热就会袭来 Things would get uncomfortably hot
给人类带来一系列的问题 and cause us some serious problems...
不过还不会像金星那么热 一点都不会 but never as hot as Venus; not even close.
在好几百万年前 That planet lost its ocean to space
这个行星上的海洋就已经消失到太空中了 billions of years ago.
没有了海洋 它就没有办法从空气中 Without an ocean, it had no way to capture CO2
捕获二氧化碳 并将它存储为矿物质 from the atmosphere and store it as a mineral.
从喷发的火山中产生的二氧化碳 The CO2 from erupting volcanoes
不断地积累 just continued to build up.
时至今日 金星上的大气要比地球重90倍 Today, that atmosphere is 90 times heavier than ours.
几乎全部由灼热的二氧化碳气体组成 Almost all of it is heat-trapping carbon dioxide.
这就是为什么金星会变成如此残酷的地狱 That's why Venus is such a ferocious inferno
生命无法在此扎根的原因 so hostile to life.
地球则恰恰与此相反 The Earth, in stunning contrast,
它是有生命的星球 is alive.
它会呼吸 It breathes...
不过很缓慢 but very slowly.
1年才能完成1次呼吸 A single breath takes a whole year.
森林里包含了地球上大部分的生命 The forests contain most of Earth's life,
大部分的森林都位于北半球 and most forests are in the Northern Hemisphere.
当北半球的春季到来 When spring comes to the north,
森林吸入空气中的二氧化碳 the forests inhale carbon dioxide from the air
并随之生长 将大地铺满绿色 and grow, turning the land green.
大气中的二氧化碳含量随之下降 The amount of CO2 in the atmosphere goes down.
秋天降临 植物落叶 随之枯萎 When fall comes and the plants drop their leaves, they decay,
将二氧化碳呼出到大气中 exhaling the carbon dioxide back into the atmosphere.
同样的过程也会发生在南半球 The same thing happens in the Southern Hemisphere
只是季节是相反的 at the opposite time of the year.
但南半球大部分是海洋 But the Southern Hemisphere is mostly ocean.
因此 是北半球的森林 So it's the forests of the north
控制了全球每年二氧化碳含量的变化 that control the annual changes in the global CO2.
地球已经像这样呼吸了 The Earth has been breathing like this
数千万年 for tens of millions of years.
从没有人注意到这一点 直到1958年 But nobody noticed until 1958,
有一位海洋学家叫查尔斯•戴维•基林 when an oceanographer named Charles David Keeling
他设计了一种方法 可以精确地测量 devised a way to accurately measure
空气中二氧化碳的含量 the amount of carbon dioxide in the atmosphere.
基林发现了地球的细微呼吸 Keeling discovered the Earth's exquisite respiration.
但他也发现了一些令人震惊的事实 But he also discovered something shocking--
有一个数字在以人类历史上前所未有的速度上升 a rapid rise, unprecedented in human history,
那就是空气中二氧化碳的整体水平 in the overall level of CO2,
至今这个变化还一直在继续 one that has continued ever since.
二氧化碳水平的惊人变化 It's a striking departure from the CO2 levels that prevailed
始于农业与文明的兴起时期 during the rise of agriculture and civilization.
实际上 In fact, the Earth has seen nothing like it
地球在过去的300万年不是这个样子 for three million years.
我们为何如此确信 How can we be so sure?
证据就记录在水里 The evidence is written in water.
地球保存着一份详细的日记 The Earth keeps a detailed diary
它就写在过去下的雪里 written in the snows of yesteryear.
气候科学家们钻出冰芯 Climate scientists have drilled ice cores
从格林兰岛和南极洲的冰川深处 from the depths of glaciers in Greenland and Antarctica.
远古的空气被困在了冰层里 The ice layers have ancient air trapped inside them.
我们可以阅读到地球大气的完整记录 We can read the unbroken record of Earth's atmosphere
一直可以追溯到8万年前 that extends back over the last 800,000 years.
在以往的所有时间内 In all that time,
大气中的二氧化碳数值从没有超过 the amount of carbon dioxide in the air never rose
每百分之一的空气中含有三百分之一的二氧化碳 above three-hundredths of one percent.
但到了二十世纪 That is, until the turn of the 20th century.
它就开始稳定而迅速的上升并保持至今 And it's been going up steadily and rapidly ever since.
现在这个数值 It's now more than 40% higher
已经比工业革命前高出了40% than before the Industrial Revolution.
通过燃烧煤 石油和煤气 By burning coal, oil and gas,
人类文明在释放出二氧化碳 our civilization is exhaling carbon dioxide
远远超过了地球所能吸收的速度 much faster than Earth can absorb it.
因此大气中的二氧化碳在不断积累 So CO2 is building up in the atmosphere.
这个星球在升温 The planet is heating up.
每一个发热的物体都能辐射出某种我们肉眼看不见的光 Every warm object radiates a kind of light we can't see with the naked eye--
那就是热红外线 thermal infrared light.
即使在黑暗中 我们的身体也能散发出不可见的热辐射 We all glow with invisible heat radiation, even in the dark.
如果用红外线观察地球 它就是这个样子 This is what the Earth looks like in the infrared.
你看到的是行星本身的发热 You're seeing the planet's own body heat.
当阳光照射到地面 Incoming light from the Sun hits the surface.
地球本身会吸收大部分的能量 The Earth absorbs much of that energy,
让地球升温 which heats the planet up
从而让地表发出红外线 and makes the surface glow in infrared light.
但空气中的二氧化碳 But the carbon dioxide in the atmosphere
又会吸收散发出的大部分热量 absorbs most of that outgoing heat radiation,
把这些热量的大部分又传回地面 sending much of it right back to the surface.
让地球变得更热 This makes the planet even warmer.
这就是所谓的温室效应 That's all there is to the greenhouse effect.
它的基本物理原理 It's basic physics,
就在于把流动的能量保存下来 just bookkeeping of the energy flow.
关于它没什么好争议的 There's nothing controversial about it.
如果大气中一点二氧化碳都没有 If we didn't have any carbon dioxide in our atmosphere,
地球就会变成一个大雪球 the Earth would just be a great big snowball,
人类也就不会存在 and we wouldn't be here.
因此 轻度的温室效应是件好事 So, a little greenhouse effect is a good thing.
可它要是变大 就会造成气候的不稳定 But a big one can destabilize the climate
甚至毁掉人类的生存方式 and wreck our way of life.
好吧 但我们怎么知道人类是问题的根源？ All right... but how do we know that we're the problem?
也许是地球本身导致二氧化碳的增加 Maybe the Earth itself is causing the rise in CO2.
也许和煤与石油的燃烧无关 Maybe it has nothing to do with the coal and oil we burn.
或许是那些该死的火山 Maybe it's those damn volcanoes.
每隔几年 西西里岛的埃特纳火山就会喷发 Every few years, Mount Etna, in Sicily, blows its stack.
每次的大规模喷发都会把几百万吨二氧化碳 Each big eruption sends millions of tons of CO2
送入空气 into the atmosphere.
如果我们把 Now, combine that with the output
地球上所有的火山喷发合计起来的话 of all the other volcanic activity on the planet.
让我们按最大数量进行科学预测 Let's take the largest scientific estimate--
每年大概会有5亿吨二氧化碳 about 500 million tons of volcanic CO2
被送入空气中 entering the atmosphere ever year.
听上去很多 对不对？ Sounds like a lot, right?
可这个数值还不到人类每年产生的二氧化碳数量的2% But that's not even two percent of the 30 billion tons of CO2
那就是1年300亿吨 that our civilization is cranking out every year.
而且 还有个很有趣的现象 And, funny thing,
大气中二氧化碳的增加量 the measured increase in CO2 in the atmosphere
与我们所知的 即是通过燃烧煤 石油和煤气产生的二氧化碳 tallies with the known amount we're dumping there
刚好相同 by burning coal, oil and gas.
火山产生的二氧化碳有一个明显的特征 Volcanic CO2 has a distinct signature--
与化石燃料燃烧时产生的二氧化碳相比 it's slightly heavier than the kind produced
它要稍微重一些 by burning fossil fuels.
我们可以分辨出这两者的差别 We can tell the difference between the two
通过对它们进行原子级别的检验 when we examine them at the atomic level.
检验结果很明显证实 空气中增加的二氧化碳 It's clear that the increased CO2 in the air
不是来自火山 is not from volcanoes.
更重要的是 气候变暖的程度与 What's more, the observed warming is as much as predicted
空气中二氧化碳增加的程度差不多 from the measured increase in carbon dioxide.
这两者紧密关联 It's a pretty tight case.
人类排放二氧化碳的证据都在这上面 Our fingerprints are all over this one.
每年30亿吨二氧化碳到底有多少? How much is 30 billion tons of CO2 per year?
如果我们把它压成一个固体 If you compressed it into solid form,
它的体积就会和 it would occupy about the same volume
多佛海岸的白色悬崖差不多 as the White Cliffs of Dover.
这就是我们每年排放到空气中的二氧化碳的数量 And we're adding that much CO2 to the air every year,
永无休止 年复一年 relentlessly, year after year.
很不幸的是 Unlucky for us, the main waste product
人类文明产生的主要垃圾产品不是物质 of our civilization is not just any substance.
而是能对全球气候调节产生 It happens to be the chief climate-regulating gas
恒温效果的毒气 年年如此 of our global thermostat, year in, year out.
过多的二氧化碳就相当于看不见的毒气 Too bad CO2 is an invisible gas.
如果我们能看到它…… Maybe if we could see it...
如果我们的眼睛能感应到二氧化碳 If our eyes were sensitive to CO2--
也许在宇宙中有这样的生物 and perhaps there are such beings in the cosmos--
如果我们能看见二氧化碳 if we could see all that carbon dioxide,
那就没有人能否定这一切 then we would overcome the denial
并充分了解到人类对大气的严重影响 and grasp the magnitude of our impact on the atmosphere.
但全球变暖的证据 But the evidence that the world is getting warmer
就在我们身边 is all around us.
首先让我们检查一下 For starters, let's just check the thermometers.
世界各地气象站的温度计 Weather stations around the world
自1880年代起 have been keeping reliable temperature records
它们一直保存着可靠的温度记录 since the 1880s,
美国宇航局用这些数据编制了一幅地图 and NASA has used the data to compile a map
地图涵盖了所有的时间段 tracking the average temperatures
用作跟踪世界各地平均气温的变化 around the world through time.
黄色意味着温度较高 Yellow means warmer temperatures
高于1880年代任何地区的平均水平 than the average, for any region in the 1880s.
橙色意味着炎热 Orange means hot.
红色意味着比炎热更热 And red means hotter.
世界已经变得比19世纪更温暖了 The world is warmer than it was in the 19th century.
那时 全球各地的气温是有史以来最均衡的 Back then, at the greatest fair the world has ever seen,
一位被遗忘的天才曾设想了一个解决问题的方案 a forgotten genius demonstrated the solution to this problem.
跟我来 Come with me.
曾经有这样一个世界 Once there was a world
它不太热也不太冷 that was not too hot and not too cold.
温度适中 It was just right.
然后有一天 这里的人们 Then there came a time when the life it sustained
开始注意到他们可爱的地球在发生变化 began to notice our lovely planet was changing.
这并不是说我们没有预见到它的到来 And it's not as if we didn't see it coming.
三十一. 关于碳酸空气中对地面温度的影响
早在1896年 As far back as 1896,
瑞典科学家斯凡特•阿伦尼斯 the Swedish scientist Svante Arrhenius
通过计算发现 如果大气中的二氧化碳含量再增加1倍 calculated that doubling the amount
大气就如温室一般
就能让北极的冰融化 of CO2 in the atmosphere would melt the Arctic ice.
到了1930年代 美国物理学家E.O.赫尔伯特 In the 1930s, the American physicist E. O. Hulburt,
在海军实验室里 at the Naval Research Laboratory,
确认了这个结果 confirmed that result.
二氧化碳令地球变热
到那时为止 这一切还依然是理论 So far, it was still just theoretical.
随后 英国工程师盖•卡伦德 But then, the English engineer Guy Callendar
人为排放二氧化碳对于气温的影响
把这些证据结合起来 向人们展示 assembled the evidence to show
二氧化碳含量与全球平均气温 that both the CO2 and the average global temperature
都在不断上升中 were actually increasing.
就算是现在 人们也可能在无意中改变了全球气候 Even now, man may be unwittingly changing the world's climate
通过文明产生的废弃物 through the waste products of his civilization.
由于人类通过工厂与汽车的排放 Due to our release, through factories
每年有超过 and automobiles every year, of more than
60亿吨的二氧化碳产生 six billion tons of carbon dioxide,
让空气吸收了更多来自于太阳的热量 which helps air absorb heat from the Sun,
大气变得越来越热 our atmosphere seems to be getting warmer.
这是不是件坏事? This is bad?
嗯 通过计算表明 Well, it's been calculated, a few degrees rise
地球温度的轻微升高 in the Earth's temperature
会让地球两极的冰帽熔化 would melt the polar ice caps.
二氧化碳与气候 "当前的理论 假设了二氧化碳会调节地球的温度 这就产生了一个很有趣的问题： 人类的活动如何影响未来的气候呢？"
1960年 卡尔•萨根在他的博士论文里 In 1960,Carl Sagan's PhD thesis
第一次计算了 included the first calculation
金星上失控的温室效应 of the runaway greenhouse effect on Venus.
这是他职业兴趣的一个部分 This was part of a career-long interest
对于行星大气 包括我们的星球的兴趣 in the atmospheres of the planets, including our own.
气候变化:我们正处于地球变暖的边缘吗?
大气中增加的二氧化碳对气候的影响
在1980制作的最初那部宇宙系列片中 卡尔•萨根警告说 In the original Cosmos series, in 1980, Carl Sagan warned...
"我们正在释放大量的二氧化碳 We are releasing vast quantities of carbon dioxide,
加剧了温室效应 increasing the greenhouse effect.
用不了多久 It may not take much
地球的气候就会失去平衡 to destabilize the Earth's climate,
把我们在宇宙中这唯一的家园 像天堂一样的地方 to convert this heaven, our only home in the cosmos,
变为人间地狱" into a kind of hell.
卡尔说过这些话之后 Since Carl spoke those words,
我们还在继续加重大气的负担 we've burdened the atmosphere of our world with an additional
每年又多增加了4千亿吨二氧化碳的排放 400 billion tons of carbon dioxide.
如果我们不改变这个现状 If we don't change our ways,
我们未来的孩子们将会面对一个什么样的星球 what will the planet be like in our children's future?
根据科学研究项目的结果 Based on scientific projections,
如果我们继续保持着现有的经济模式不变 if we just keep on doing business as usual,
我们的子孙将会面对艰险的未来 our kids are in for a rough ride.
致命的热浪 破纪录的干旱 Killer heat waves, record droughts,
不断升高的海平面 大规模的物种灭绝 rising sea levels, mass extinction of species.
我们曾从前人手中继承了一个富饶的世界 We inherited a bountiful world
气候相对稳定 made possible by a relatively stable climate.
农业繁荣 文明兴盛 Agriculture and civilization flourished
延续了千年之久 for thousands of years.
可现在 人类的冷漠与贪婪把这一切推向了危险的境地 And now, our carelessness and greed put all of that at risk.
好吧 如果科学家们有那么厉害 Okay, so if we scientists are so good
可以作出关于气候的如此长远的可怕预测 at making these dire, long-term predictions about the climate,
那为什么就不能把天气测准一点呢? How come we're so lousy about predicting the weather?
还有 今年我家乡的冬天特别寒冷 Besides, this year, we had a colder winter in my town.
我们的科学家知不知道 For all us scientists know,
说不定我们现在面对的是全球变冷呢 we could be in for global cooling.
天气和气候是不同的两个概念 Here's the difference between weather and climate...
天气指的是短时期内的大气变化 Weather is what the atmosphere does in the short term--
可能是几小时 也可能是几天 hour to hour, day to day.
天气是变化莫测的 Weather is chaotic, which means that even
这意味着即使是微小的干扰也能引起大规模的变化 a microscopic disturbance can lead to large-scale changes.
这就是为什么对十天后的天气预测是没有用的 That's why those ten-day weather forecasts are useless.
巴厘岛上的一只蝴蝶扇动了翅膀 六周以后 A butterfly flaps its wings in Bali, and six weeks later,
你在缅因州的户外婚礼就会被狂风暴雨毁掉了 your outdoor wedding in Maine is ruined.
气候研究的则是长时期的天气的平均变化 Climate is the long-term average
跨越幅度有好几年 of the weather, over a number of years.
它是由这个星球上能改变大气能量平衡的力量决定的 It's shaped by global forces that alter the energy balance
比如说 阳光的变化 in the atmosphere, such as changes in the Sun,
地球自转轴的倾斜度 the tilt of the Earth's axis,
地球反射回太空的日照量 the amount of sunlight the Earth reflects back to space
空气中的温室气体浓度 and the concentration of greenhouse gases in the air.
它们当中任何一个的变化都能影响气候 A change in any of them affects the climate
而且它们的变化方式是大致可以预测的 in ways that are broadly predictable.
我的这位小朋友忽左忽右的走路方式 My friend's meandering
就好比是短期的波动 represents the short-term fluctuations--
这就是天气 that's weather.
基本上很难预测 It's almost impossible to predict
谁知道它等会儿又会对什么感兴趣 what'll attract his interest next,
不过我们不难知道它游荡的范围 but not hard to know what the range of his meandering will be,
因为我用皮带牵着它 because I'm holding him on a leash.
人不能直接观察到气候 We can't observe climate directly--
因为我们所见的是天气 all we see is the weather--
但经过好几年后推算出的平均天气变化 but the average weather, over the course of years,
会揭示出一个模式 reveals a pattern.
这就是一个长期的趋势 I represent that long-term trend,
这就是气候 which is climate.
把注意力放在人身上 别看狗 Keep your eye on the man, not the dog.
天气很难预测 就像我的这位小朋友 Weather is hard to predict, like my friend here,
但气候是可以预测的 but climate is predictable.
在地球漫长的历史上 气候曾经变换过好多次 Climate has changed many times in the long history of the Earth
每一次都是受某种全球性力量作用的结果 but always in response to a global force.
现在影响气候变化最强的力量就是 The strongest force driving climate change right now
由于燃烧化石燃料而不断增加的二氧化碳 is the increasing CO2 from the burning of fossil fuels,
它留住了更多的太阳热量 which is trapping more heat from the Sun.
这些多出来的能量必须有个去处 All that additional energy has to go somewhere.
有些能量让空气升温 Some of it warms the air.
大部分的能量则被海洋吸收 Most of it ends up in the oceans.
全世界的海洋现在都在变暖 All over the world, the oceans are getting warmer.
最明显的就是北冰洋 It's most obvious in the Arctic Ocean
以及它周围的陆地 and the lands that surround it.
好吧 如果说我们正在失去一些夏季的海冰 Okay, so we're losing the summer sea ice
不过那个地方又是没什么人去的 in a place where hardly anyone ever goes.
我干嘛要关心北极有没有冰呢？ What do I care if there's no ice around the North Pole?
冰是地球最亮的自然表面 Ice is the brightest natural surface on the Earth,
广阔的海洋则是最暗的自然表面 and open ocean water is the darkest.
冰能把阳光反射回太空 Ice reflects incoming sunlight back to space.
水则会吸收阳光而变暖 Water absorbs sunlight
这会让更多的冰融化 and gets warmer, which melts even more ice,
让更多的海洋水面暴露出来 which exposes still more ocean surface
并吸收更多的阳光 to absorb even more sunlight.
这就是所谓的正反馈效应 This is what we call a positive feedback loop.
这是能把二氧化碳引起的热效应放大的 It's one of many natural mechanisms that magnify
许多种自然机制中的一个 any warming caused by CO2 alone.
我们现在是在阿拉斯加的德鲁角 We're at Drew Point, Alaska,
这里是北冰洋的边缘 on the edge of the Arctic Ocean.
当我出生的时候 这里的海岸线伸出去有1英里多 When I was born, the shoreline was a mile farther out,
它过去曾以每年20英尺的速度缩减 and it was breaking off at a rate of about 20 feet per year.
现在…… Now...
缩减的速度达到了每年50英尺 it's being eaten away at about 50 feet per year.
北冰洋正在变暖 The Arctic Ocean is warming
而且变暖的速度在不断增快 and at an increasing rate.
所以每年里有大部分时间这里是没有冰的 So it's ice-free during more of the year.
有更多的海岸线因此暴露出来 That leaves the shore here
被风暴所侵蚀 more exposed to erosion from storms,
这让另一种力量变得更强大 which are also getting more powerful,
这种力量能影响气候的变化 another effect of climate change.
阿拉斯加北部 西伯利亚 加拿大 The northern reaches of Alaska, Siberia and Canada
这些地方的大部分是永久性冻土 are mostly permafrost,
地面被冻结超过千年 ground that has been frozen year-round for millennia.
它里面含有很多有机质 It contains lots of organic matter,
过去的树叶与树根 old leaves and roots from plants
它们曾生长在数千年前 that grew thousands of years ago.
由于北冰洋地区的升温速度在加快 Because the Arctic regions are warming faster
比地球上其他地区都要快 than anywhere else on Earth,
永久性冻土开始融化 the permafrost is thawing
冻土中的东西开始腐烂 and its contents are rotting,
效果就和冰箱断电差不多 just like when you unplug the freezer.
融化的冻土释放出二氧化碳 The thawing permafrost is releasing carbon dioxide
还有甲烷 这是一种更厉害的的温室气体 and methane, an even more potent greenhouse gas,
它们都进入了大气中 into the atmosphere.
这让世界变得更热 This is making things even warmer,
还有一个正反馈效应的例子 another example of a positive feedback mechanism.
世界的永久性冻土层中储存有大量的碳 The world's permafrost stores enough carbon
足以让大气中的二氧化碳再增加一倍 to more than double the CO2 in the atmosphere.
按照现在的速度 At the rate we're going,
全球变暖很快就要实现大部分了 global warming could release most of it
时间就是本世纪末 by the end of the century.
人类也许正在将气候推上一条不归路 We might be tipping the climate past a point of no return
让它走向无法预知的一面 into an unpredictable slide.
好吧 如果空气 水 陆地 Okay, the air, the water
还有其他的一切都变暖了 and the land are all getting warmer,
全球变暖真的发生了 so global warming is really happening.
也许这不是人类的错 But maybe it's not our fault.
也许这是自然造成的 Maybe it's just nature.
也许是因为太阳 Maybe it's the Sun.
不 也许不是因为太阳 No, it's not the Sun.
我们这几十年来一直在密切的观测太阳 We've been monitoring the Sun very closely for decades,
而太阳输送的能量一直都没有变过 and the solar energy output hasn't changed.
还有 地球现在是 What's more, the Earth is warming more at night
晚上比白天更暖 than in daytime,
冬天比夏天更暖 and more in winter than in summer.
这是符合温室效应规律的 That's exactly what we expect from greenhouse warming,
与太阳输送能量的增加 but the opposite of what increased solar output
一点关系都没有 would cause.
怀疑是没有用的 现在的一切清楚表明 It's now clear beyond any reasonable doubt
人类正在改变气候 that we are changing the climate.
太阳根本就不是元凶 The Sun isn't the problem.
而拯救这一切的方案 But it is the solution,
人类早已制备了很久 and we've known this for a long time,
早在比你想象中更久远的年代 much longer than you might think.
巴黎 1878年9月 Paris, September 1878.
埃菲尔铁塔还要过好多年才会开始建造 The Eiffel Tower won't be built for years to come.
世博会
世界上最壮观非凡的景象 the world has ever seen.
自由女神像宏伟的头部 The magnificent head of the Statue of Liberty
才刚刚造好 has just been completed.
全球各地数千家展商 Thousands of exhibitors from around the planet
在巴黎的66英亩土地上 covered 66 acres of Paris
布满了他们的发明与产品 with their inventions and goods.
爱迪生发明的灯泡还要在好几年后才 Edison's first public demonstration of the light bulb
第一次向公众展示 will not take place for another year.
电气设备还没有出现 There's no such thing as electrical appliances.
人们还不会开开关 按按钮 People don't flick switches and press buttons.
这是一个人牵马拉的世界 It's a hand-cranked, horse-drawn world.
这就是我们要说到的那个人 That's the guy we came to see,
那个有奇怪胡子的人 the one with the crazy moustache.
他是一个数学老师 名叫奥古斯丁•莫超 He's a math teacher named Augustin Mouchot.
记住 这是在1878年 Remember, it's 1878.
一个由煤气灯统治的世界 This is a world lit mostly by gaslight.
汽车还要过好多年才会发明 The automobile is still years away.
但莫超的发明足以让观众目瞪口呆 But Mouchot, here, is dazzling the crowd
那是一个太阳能聚能设备 with his solar power concentrator.
太阳属于我们每一个人 The Sun belongs to all of us!
就算它距离我们1亿5千万公里远 Even though it is 150 million kilometers away from us,
感受一下它那强悍的威力吧 feel its awesome power!
我的发明能把太阳散发的免费的能量集中起来 My invention concentrates the free energy of the Sun
把它转化为机械运动 and converts it into mechanical motion.
为任何一种机器提供能量 It can power any kind of machine.
它可以用来发电或者是让印刷机运转 It can produce electricity or run a printing press
甚至是在热天制冰 or make ice on a hot day.
等着瞧吧 Et voilà !
想想吧 Think of it,
既然阳光能转化为冰块 sunlight converted into ice.
想想吧 朋友们 如果我们能把丰富的太阳能利用起来 You see, my friends, what wonders we can work
我们能做出什么样的奇迹来 if we harness the bounteous energy of the Sun.
世界上的煤总有一天会用完 The world will someday run out of coal,
但辉煌的太阳永远在那里照耀着我们 but the magnificent Sun will always be there for us.
莫超获得了这一届世界博览会的金奖 Mouchot took home the gold medal from the fair.
但煤炭的价格下跌了 But the price of coal tumbled,
价格如此之低以至于人们对太阳能再也没有兴趣 becoming so cheap that there was no interest in solar energy.
此外 当时还没有人明白 Besides, no one understood, back then,
燃烧化石燃料的真正代价是什么 what the true cost was of burning fossil fuel.
莫超的研究经费被砍掉了 Mouchot's research funding was cut off.
35年后 也就是二十世纪初期 35 years later, in the early years of the 20th century,
通向另一个未来的另一扇大门被打开了 another door opened to an alternative future.
它发生在埃及 尼罗河岸边 It happened in Egypt, on the banks of the Nile.
未来的时间旅行者们记住了 Memo to future time travelers...
这是一个对避免气候变化而言 this would be an excellent entry point
绝佳的起点 for averting climate change.
1913年 埃及 Egypt, 1913.
这是来自美国费城的弗兰克•舒曼 That's Frank Shuman of Philadelphia.
他只读过3年书 He's only had three years of schooling,
但他天才的创造发明能力弥补了这一切 but his genius for innovation more than makes up for that.
在30岁以前 舒曼发明了安全玻璃 Before he was 30, Shuman had invented safety glass.
它被广泛用在汽车与飞机上 挽救了无数的生命 Its use in automobiles and skylights saved countless lives
也让他变得非常有钱 and made him a very rich man,
有钱 让他能去追求自己真正的梦想 rich enough to pursue his real passion,
太阳能 solar energy.
舒曼领导着一支团队设计并建造了 Shuman led the team that designed and built
一组太阳能聚能设备 an array of solar energy concentrators.
它能驱动蒸汽机 It could power a steam engine.
舒曼希望利用太阳能 Shuman is hoping to use the Sun's power
以灌溉沙漠 to irrigate the desert
让它重新变绿 and turn it green.
舒曼的太阳能发电站 The official inauguration
在1913年正式启动 of Shuman's solar power plant, in 1913,
这是个了不起的成就 was a dazzling success.
他发明了一种实用的方法 He had invented a practical way to tap the Sun's energy
让太阳能得以实现工业规模的应用 on an industrial scale,
让太阳能比煤更便宜 making solar energy even cheaper than coal.
英德两国政府 The British and German governments
给予了舒曼慷慨的赞助 both offered Shuman generous funding
让他去创造发明 to develop his invention.
这是一种理想的丰富的能量来源 It was the ideal source of abundant power
尤其是在热带地区 in tropical regions,
那里进口煤的价格比较昂贵 where imported coal was prohibitively expensive.
但舒曼有更大的梦想 But Shuman was dreaming even bigger.
在给《科学美国人》写的一封信中 In a letter to Scientific American,
他对他的太阳能发电厂进行了计算 he calculated that his solar power plants,
如果能将它安装在一个像撒哈拉沙漠那样的地区 if deployed in an area of the Sahara Desert
只需要方圆150英里的面积 就能提供 only 150 miles on a side, could supply as much power
足以让世界所有工厂消费的能量 as consumed by all the industries of the world.
但这一切最终没有发生 But it was not to be.
石油 这种液体化石燃料的市场 The market for a liquid fossil fuel, petroleum,
随船运而蓬勃发展起来 was exploding for shipping,
家庭供热 汽车与卡车 home heating, and cars and trucks.
石油很丰富 甚至比煤还便宜 Oil was abundant, cheaper even than coal,
它很容易就能获得 易于加工 and much easier to get out of the ground and process.
要把煤装满一艘船 需要100个人干上1周 It took 100 men a week to fuel a ship with coal,
但如果是装石油 but with oil, one man could do the job
1个人干上1天就可以了 in a single day.
舒曼在沙漠中取得成功后的第2年 A year after Shuman's triumph in the desert,
第一次世界大战爆发 World War I broke out.
他的太阳能集热器被回收 变成了武器 His solar collectors were recycled into weapons.
舒曼梦想中的太阳能发电的文明社会 Frank Shuman's dream of a solar-powered civilization
只有等到下一个世纪 would have to wait another century
才能获得重生的机遇 before it was reborn.
在我们这个世界上 There's another inexhaustible source of clean energy
还有另一种取之不尽的清洁能源 for the world.
风能本身也是由太阳能产生的 The winds themselves are solar-powered,
太阳驱动着风与波浪 because our star drives the winds and the waves.
与太阳能集热器不同 Unlike solar collectors,
风能发电厂只需要很少的土地 wind farms take up very little land,
如果是在海边 那就一点陆地都用不到 and none at all, if offshore,
海上的风力是最强的 where the winds are strongest.
如果人类能把世界上百分之一的风能利用起来 If we could tap even one percent of their power,
就会有充足的能源供文明社会运作 we'd have enough energy to run our civilization.
而每个小时落在地球上的太阳能量 And more solar energy falls on Earth in one hour
都超过我们人类社会 than all the energy our civilization consumes
1年消费的能量总和 in an entire year.
只要人类能把很小一部分 If we could harness a tiny fraction
可用的太阳能与风能利用起来 of the available solar and wind power,
人类就会有永久充足的能源供应 we could supply all our energy needs forever,
而无需向大气中排放任何的碳 and without adding any carbon to the atmosphere.
现在时犹未晚 It's not too late.
未来仍值得我们奋斗 There's a future worth fighting for.
为何我能这样肯定？ How do I know?
我们每个人都是艰苦斗争后的幸存者 Every one of us comes from a long line of survivors.
如果不懂得适应环境 人类这个物种就不会存在 Our species is nothing if not adaptive.
因为我们的先人学会了 It was only because our ancestors learned
目光长远 应时而动 to think long-term, and act accordingly,
人类才会有今天 that we're here at all.
前有困阻 但我们不能退避 We've had our backs to the wall before,
我们要迈向新的高度 and we came through to scale new heights.
实际上 人类历史上所取得的很多伟大的成就 In fact, the most mythic human accomplishments of all
都是来自最黑暗的时刻 came out of our darkest hour.
曾经有这样一个世界 Once there was a world
6万枚核武器如箭在弦上 时刻待发 rigged with 60,000hair-triggered nuclear weapons.
这场厮杀发生在 The combatants were
地球上两个最强大的国家之间 the two most powerful countries on Earth,
他们死也要缠在一起 and they were locked in a deadly embrace,
每一个国家都宣称 each vowing that they would rather see
宁愿让这个世界玉石俱焚 everything we love destroyed
也不要不让别人得到她 than submit to the will of the other.
当时我才3岁 When I was three years old,
有史以来威力最强的人造炸弹 the largest man-made explosion of all time
刚由苏联引爆 was detonated by the Soviet Union.
旧的恐惧刚刚消退 新的恐惧随之而来 That terror has subsided, to be replaced by new fears.
地球上2000个最大的城市 The danger that the 2,000 largest cities on Earth
随时会有在一个下午内化为废墟的危险 would be reduced to rubble in the space of an afternoon
但跟这个比都算不上什么 is no longer one of them.
美国与苏联之间的 The nuclear rivalry between the United States
核军备竞赛 and the Soviet Union
创造了一个副产品 had another by-product.
阿波罗登月计划 The Apollo missions to the Moon were an extension
就是美苏间军备竞争的产物 of the arms race that raged between them.
把人送上地球轨道 Sending people to orbit the Earth
或是送到月球 都需要大型的 可靠的 or go to the Moon requires big, reliable,
大推力火箭 而这正是 powerful rockets-- precisely the same technology
携带核弹头所需的科技 you need to carry a nuclear warhead
让它可以飞越半个地球 halfway around the planet
摧毁敌国的最大城市 to destroy your enemy's largest cities.
我相信这个国家 "I believe that this nation
一定会达成这个目标 should commit itself to achieving the goal,
那就是在未来的十年里 把人送上月球 before this decade is out, of landing a man on the Moon
并让他安全的返回地球 and returning him safely to the Earth."
肯尼迪总统1961年的演讲 President Kennedy's 1961 speech
让这个国家兴奋起来 electrified the nation,
里面提到了很多让人印象深刻的远景计划 and it contained much that was remarkably prophetic--
但在关于探月计划的内容中 but not a word about a scientific objective
没有一个字是跟科学项目有关的 for going to the Moon.
没有关于对月球起源的探索 No questions about the Moon's origin
或是带回样品进行分析的想法 or the hope of bringing back samples to analyze.
阿波罗计划与科学无关 它原本就是为了 No, the Apollo missions were conceived
展示超级大国的实力 as a demonstration of the superior power
以及战术导弹的精度 and precision of our strategic missiles.
但可笑的是 But a funny thing happened to us...
在探月的道路上 on our way to the Moon.
当人类回望故乡时 We looked homeward...
却发现了另一个世界 and discovered another world--
我们自己的世界 our own.
第一次 我们这些地球的居民 For the first time, we inhabitants of Earth
可以后退一步 看看地球到底是什么样子 could step back and see it as it really is--
这是一个不可分割的世界 one world, indivisible,
在浩瀚的宇宙中它是如此的渺小 and kind of small in the cosmic context.
不管是为了什么原因 让我们集结了大量的资源 Whatever the reason we first mustered the enormous resources
投入到阿波罗计划上 required for the Apollo program,
不管冷战时期的我们是如何深陷民族主义的思潮 however mired it was in Cold War nationalism
以及对杀人武器的追求 and the instruments of death,
我们仍不可避免地认识到了 the inescapable recognition of the unity
地球是脆弱而不可分割的统一体 and fragility of the Earth
每一个明亮发光的点都是它的组成部分 is its clear and luminous dividend,
这是阿波罗计划的意外收获 the unexpected gift of Apollo.
一个致力于死亡竞赛的项目 A project conceived in deadly competition
让我们认识了这个地球共同体 made us recognize our community.
是什么样的巨人修建了这个世界奇观？ What titan built this wonder of the world?
是菲律宾伊富高省的人民 It was the Ifugao people of the Philippines,
依靠着他们的双手辛勤劳作 working with not much more than their hands.
在大约1万年前 我们在世界各地的祖先 About 10,000 years ago, our ancestors all over the world
利用了另一种形式的气候突变 took advantage of another form of climate change,
冰河时代间歇期中出现的温和天气 the gentler climate of the intermission in the ice age--
他们发明了农业 they invented agriculture.
他们放弃了无休止的 They gave up the ceaseless wandering,
流浪 游猎以及采集的生活方式 hunting and gathering that had been their way of life
这种方式曾延续了1百万年之久 for a million years or so,
他们定居下来 生产食物 to settle down and produce food.
他们发现耕作农田 They found a way to harvest
能让他们比先人通过自然环境 ten to a hundred times more solar energy
获得要高出十到百倍之多的太阳能 than the environment naturally provided for their ancestors.
世界各地的人们艰难地实现了 People all over the world made the difficult transition
从游牧文化向农耕文化的转变 from nomadic cultures to agricultural ones
这是一种更有效的使用太阳能的方式 that used solar energy more efficiently.
这让文明兴盛起来 It gave rise to civilization.
我们就站在那些辛勤劳作的先人的肩上 We stand on the shoulders of those who did the hard work
他们为我们实现最基础的转变 that such a fundamental transformation required.
现在 该轮到我们了 Now... it's our turn.
曾经有这样一个世界…… Once there was a world...
如果在金星上曾有过生命 他们也不会有机会 If life ever existed on Venus, it would have had no chance
扭转这个世界走向地狱的命运 to avert the hellish destiny of this world.
这种失控的温室效应是无法阻挡的 This runaway greenhouse effect was unstoppable.
曾经 Once...
有这样一个世界 there was a world...
那是我们的世界 ours.
就是现在的世界 And that world is now.
没有任何科学或技术上的障碍 There are no scientific or technological obstacles
会阻止我们保护这个世界 to protecting our world
保护这个世界上珍贵的生命 and the precious life that it supports.
一切都取决于 It all depends...
我们真正珍惜的是什么 on what we truly value...
我们能否付诸于行动 and if we can summon the will to act.
"为什么" 有人问 为什么要选择月亮 But why, some say, the Moon?
为什么把它作为我们的目标？ Why choose this as our goal?
他们也许还会问 And they may well ask,
我们为什么要登上世界的最高峰？ why climb the highest mountain?
而我们选择了登月 We choose to go to the Moon...
我们选择了在十年内登月 ...we choose to go to the Moon in this decade
我们还要做其他的事情 and do the other things,
不是因为它们很容易 而是因为它们很难 not because they are easy, but because they are hard.
中文翻译 幸福的微笑 timhal
原字幕取自射手 由HDWinG字幕组修正 请勿去掉制作者信息