What do I know that would cause me, a reticent, Midwestern scientist, to get myself arrested in front of the White House protesting? And what would you do if you knew what I know? Let's start with how I got to this point. I was lucky to grow up at a time when it was not difficult for the child of a tenant farmer to make his way to the state university.
我知道了些什么, 会驱使我这样一个 沉默寡言、来自中西部的科学家 到白宫门前去抗议 而被捕? 而你又会怎样做 如果你知道我所知道的? 我们从我的成长历程讲起。 我很幸运。 在我成长的那个年代, 一个佃农的孩子 想上州立大学还不那么难。
And I was really lucky to go to the University of Iowa where I could study under Professor James Van Allen who built instruments for the first U.S. satellites. Professor Van Allen told me about observations of Venus, that there was intense microwave radiation. Did it mean that Venus had an ionosphere? Or was Venus extremely hot? The right answer, confirmed by the Soviet Venera spacecraft, was that Venus was very hot -- 900 degrees Fahrenheit. And it was kept hot by a thick carbon dioxide atmosphere.
我还不是一般得幸运。 我大学去了爱荷华州立大学。 在那里,我得到了James Van Allen教授的悉心指教。 Van Allen教授为美国最早的卫星 制造仪器。 教授告诉我, 对金星的观察显示, 金星上有强烈的微波辐射。 这是表明金星上有电离层, 还是说金星上非常热? 经苏联的金星航天器肯定, 正确的答案是, 金星上非常热—— 温度高达900华氏度。 因为金星上空有一层厚厚的二氧化碳气层, 这个高温得以一直保持。
I was fortunate to join NASA and successfully propose an experiment to fly to Venus. Our instrument took this image of the veil of Venus, which turned out to be a smog of sulfuric acid. But while our instrument was being built, I became involved in calculations of the greenhouse effect here on Earth, because we realized that our atmospheric composition was changing. Eventually, I resigned as principal investigator on our Venus experiment because a planet changing before our eyes is more interesting and important. Its changes will affect all of humanity.
我非常幸运地加入了国家航空航天局, 并成功地提出了一项 飞往金星的实验。 我们的仪器拍摄到这张照片。 照片上正是金星的面纱。 这层面纱实际上是 一层含硫酸的雾。 但就在我们制造仪器期间, 我参与 计算地球上的 温室效应, 因为我们意识到 我们的大气层成分正在发生变化。 最终,我辞去了 我们金星实验组 首席调查员的职务, 因为一颗就在我们眼前变化的行星 要更有趣,也更重要。 它的变化会影响到全人类。
The greenhouse effect had been well understood for more than a century. British physicist John Tyndall, in the 1850's, made laboratory measurements of the infrared radiation, which is heat. And he showed that gasses such as CO2 absorb heat, thus acting like a blanket warming Earth's surface.
一个世纪来, 人类已充分地了解了温室效应。 英国物理学家John Tyndall 在19世纪50年代时 对红外辐射 也就是热辐射 进行了实验测量。 他向我们展示,二氧化碳等气体吸收热, 就像是一层毯子, 给地球的表面加温。
I worked with other scientists to analyze Earth climate observations. In 1981, we published an article in Science magazine concluding that observed warming of 0.4 degrees Celsius in the prior century was consistent with the greenhouse effect of increasing CO2. That Earth would likely warm in the 1980's, and warming would exceed the noise level of random weather by the end of the century. We also said that the 21st century would see shifting climate zones, creation of drought-prone regions in North America and Asia, erosion of ice sheets, rising sea levels and opening of the fabled Northwest Passage. All of these impacts have since either happened or are now well under way.
我和其他科学家 一起分析地球的气候变化。 在1981年, 我们在《科学》杂志上发表了一篇论文, 我们的结论是, 在上个世纪, 地球的温度提升了0.4摄氏度, 这和更多的二氧化碳 带来温室效应是相符的。 地球很有可能会在20世纪80年代变暖, 到20世纪末, 地球变暖的严重程度将超过 随机天气带来的噪音干扰。 我们还提出到21世纪 地球的气候区将发生变化, 北美和亚洲会 出现易旱区; 冰盖将融化,海平面将上升, 传说中的西北通道将打开。 从我们发表论文起, 所有的这些影响都已经发生了, 或正在发生。
That paper was reported on the front page of the New York Times and led to me testifying to Congress in the 1980's, testimony in which I emphasized that global warming increases both extremes of the Earth's water cycle. Heatwaves and droughts on one hand, directly from the warming, but also, because a warmer atmosphere holds more water vapor with its latent energy, rainfall will become in more extreme events. There will be stronger storms and greater flooding. Global warming hoopla became time-consuming and distracted me from doing science -- partly because I had complained that the White House altered my testimony. So I decided to go back to strictly doing science and leave the communication to others.
我们那篇论文上了《纽约时报》的头版, 在20世纪80年代, 我得以向国会证明我的发现。 在陈述中,我强调 全球变暖会加剧地球水循环的 两个极端。 一方面,变暖会直接 加剧热浪和干旱, 但同时,因为一个更暖的大气层 会保存更多的水汽 和其潜在能量, 降雨活动也将变得 更为极端。 风暴会变得更强,洪水会变得更猛烈。 全球变暖像是个套圈游戏, 我在上面花的时间越来越多, 都没心思做科研了—— 其中一个原因是我之前抱怨说 白宫修改了我的证词。 于是我决定回归到 只做科研, 把这些跟人沟通的活儿都留给别人。
By 15 years later, evidence of global warming was much stronger. Most of the things mentioned in our 1981 paper were facts. I had the privilege to speak twice to the president's climate task force. But energy policies continued to focus on finding more fossil fuels. By then we had two grandchildren, Sophie and Connor. I decided that I did not want them in the future to say, "Opa understood what was happening, but he didn't make it clear." So I decided to give a public talk criticizing the lack of an appropriate energy policy.
15年后, 全球变暖的证据越来越明显。 我们在1981的那篇论文里提到的大多数东西 都变成了事实。 我很荣幸地两次 在总统的气候专案组前演讲。 但是能源政策的重点依旧是 找到更多的化石燃料。 那时我已经有一个孙子和一个孙女, Sophie和Connor。 我决定 我不希望他们在将来说, “爷爷知道发生了些什么, 但他没有告诉大家。“ 于是我决定做场公众演讲, 批评政府没有一项合适的能源政策。
I gave the talk at the University of Iowa in 2004 and at the 2005 meeting of the American Geophysical Union. This led to calls from the White House to NASA headquarters and I was told that I could not give any talks or speak with the media without prior explicit approval by NASA headquarters. After I informed the New York Times about these restrictions, NASA was forced to end the censorship. But there were consequences. I had been using the first line of the NASA mission statement, "To understand and protect the home planet," to justify my talks. Soon the first line of the mission statement was deleted, never to appear again.
2004年我在爱荷华大学做了演讲, 2005年我在 美国地球物理联盟的会议演讲。 因为这些演讲, 从白宫到国家航空航天局总局都纷纷给我打电话, 告诉我如果我没有得到 航空航天局总局的明确批准, 我就不能做演讲或者联系媒体。 在我告诉《纽约时报》 我言论受到限制后, 国家航空航天局取消了对我的审查。 但这是造成了其他后果。 之后我一直在用 国家航空航天局的任务声明的第一句话, “为了了解和保护我们的地球家园”, 来给我的演讲作个幌子。 很快航空航天局的任务声明的第一句话 就被删除了,以后也不会再出现了。
Over the next few years I was drawn more and more into trying to communicate the urgency of a change in energy policies, while still researching the physics of climate change. Let me describe the most important conclusion from the physics -- first, from Earth's energy balance and, second, from Earth's climate history.
在之后的几年里, 我对宣传 改变能源政策的紧急性 越来越认真, 同时我还在研究气候变化物理。 我来讲一下物理研究得出的最重要的结论。 首先,从地球能量平衡角度; 其次,从地球气候历史角度。
Adding CO2 to the air is like throwing another blanket on the bed. It reduces Earth's heat radiation to space, so there's a temporary energy imbalance. More energy is coming in than going out, until Earth warms up enough to again radiate to space as much energy as it absorbs from the Sun. So the key quantity is Earth's energy imbalance. Is there more energy coming in than going out? If so, more warming is in the pipeline. It will occur without adding any more greenhouse gasses.
向空气中排入二氧化碳 就像是在床上又加了床毯子。 它减少从地球散向宇宙的热辐射, 造成暂时性的能量不平衡。 进入地球的能量 比离开地球的能量多, 直到地球继续升温 再次向太空辐射出 它从太阳吸收到的同样多的能量。 这其中的关键量 是地球的能量不平衡。 进入地球的能量 是否比离开地球的多? 如果是的,更严重的变暖正在萌生。 地球会继续升温,虽然温室气体没有增多。
Now finally, we can measure Earth's energy imbalance precisely by measuring the heat content in Earth's heat reservoirs. The biggest reservoir, the ocean, was the least well measured, until more than 3,000 Argo floats were distributed around the world's ocean. These floats reveal that the upper half of the ocean is gaining heat at a substantial rate. The deep ocean is also gaining heat at a smaller rate, and energy is going into the net melting of ice all around the planet. And the land, to depths of tens of meters, is also warming.
现在, 通过测量地球热储层中的热量, 我们能精确地 测量出地球的能源不平衡。 最大的热储层,海洋,也曾是被测量得最不精确的, 直到3000多个Argo浮标 被分散到海洋各地。 这些浮标显示 海洋的上半层 正在飞快地吸收热量。 深洋也在吸收热量,虽然速度要慢一些, 吸收的热量不断进到 地球上的融冰中。 陆地到十米深的地方, 也在升温。
The total energy imbalance now is about six-tenths of a watt per square meter. That may not sound like much, but when added up over the whole world, it's enormous. It's about 20 times greater than the rate of energy use by all of humanity. It's equivalent to exploding 400,000 Hiroshima atomic bombs per day 365 days per year. That's how much extra energy Earth is gaining each day. This imbalance, if we want to stabilize climate, means that we must reduce CO2 from 391 ppm, parts per million, back to 350 ppm. That is the change needed to restore energy balance and prevent further warming.
现在的总能量不平衡 大概有每平方米0.6瓦。 这听起来好像不是很多, 但把全世界的都加起来,这个数字就大得惊人。 它大概比所有人类用能量的 多出20倍。 它等同于一年365天 每天炸掉40万个 广岛原子弹。 地球每天都在吸收 这样多的额外能量。 这个不平衡意味着 如果我们想要稳定气候的话, 我们就必须降低二氧化碳浓度, 从391ppm,即百万分之三百九十一, 降回到350ppm。 如果我们想重建能量平衡,阻止地球变得更暖, 我们就必须做这样的改变。
Climate change deniers argue that the Sun is the main cause of climate change. But the measured energy imbalance occurred during the deepest solar minimum in the record, when the Sun's energy reaching Earth was least. Yet, there was more energy coming in than going out. This shows that the effect of the Sun's variations on climate is overwhelmed by the increasing greenhouse gasses, mainly from burning fossil fuels.
否认气候变化的人说, 太阳是地球气候变化的主要原因。 但是我们测量到的能量不平衡发生在 自人类记录以来太阳活动最弱时期, 这期间太阳到达地球的能量是最少的。 然而,地球收到的能量还是比散发的多。 这表明太阳辐射对气候的影响 已经被增加的温室气体减弱, 这些气体主要来自化石燃料的燃烧。
Now consider Earth's climate history. These curves for global temperature, atmospheric CO2 and sea level were derived from ocean cores and Antarctic ice cores, from ocean sediments and snowflakes that piled up year after year over 800,000 years forming a two-mile thick ice sheet. As you see, there's a high correlation between temperature, CO2 and sea level. Careful examination shows that the temperature changes slightly lead the CO2 changes by a few centuries. Climate change deniers like to use this fact to confuse and trick the public by saying, "Look, the temperature causes CO2 to change, not vice versa." But that lag is exactly what is expected.
现在想想地球的气候史。 这些全球温度的曲线, 大气层二氧化碳和海平面的曲线, 是通过测量海洋芯、南极冰芯、 和海洋沉淀物和雪花得到的。 80多万年来, 这些沉淀物和雪花不断积累, 最后形成了一个2英里厚的冰盖。 大家都可以看到,温度、二氧化碳和海平面之间 有着极大的关联。 仔细的研究显示 气温变化 会引发几世纪后的 二氧化碳变化。 否定气候变化的人喜欢用这个事实 来迷惑和愚弄大众。 他们会说:“看,是温度引起了二氧化碳变化, 而不是二氧化碳引起温度变化。” 但是这正是 我们所预期的。
Small changes in Earth's orbit that occur over tens to hundreds of thousands of years alter the distribution of sunlight on Earth. When there is more sunlight at high latitudes in summer, ice sheets melt. Shrinking ice sheets make the planet darker, so it absorbs more sunlight and becomes warmer. A warmer ocean releases CO2, just as a warm Coca-Cola does. And more CO2 causes more warming. So CO2, methane, and ice sheets were feedbacks that amplified global temperature change causing these ancient climate oscillations to be huge, even though the climate change was initiated by a very weak forcing.
经过数十万年,地球的轨道 会产生小小的变化, 这些变化会改变 地球各部分得到的阳光。 如果高纬度地区 在夏天得到更多的日照,冰盖就会融化。 减少后的冰盖会 让地球变得更暗, 地球因此会吸收更多的阳光, 变得更加温暖。 升温的海洋会释放二氧化碳, 就像升温的可口可乐一样。 更多的二氧化碳会引发更严重的变暖。 因此,二氧化碳、甲烷和冰盖 都是放大了 全球温度变化的反馈, 尽管气候变化最初是因小小的变化而起, 这些古老的气候变化指数 也会变得非常大。
The important point is that these same amplifying feedbacks will occur today. The physics does not change. As Earth warms, now because of extra CO2 we put in the atmosphere, ice will melt, and CO2 and methane will be released by warming ocean and melting permafrost. While we can't say exactly how fast these amplifying feedbacks will occur, it is certain they will occur, unless we stop the warming. There is evidence that feedbacks are already beginning. Precise measurements by GRACE, the gravity satellite, reveal that both Greenland and Antarctica are now losing mass, several hundred cubic kilometers per year. And the rate has accelerated since the measurements began nine years ago. Methane is also beginning to escape from the permafrost.
重要的问题是 这些同样的放大的反馈 会出现在现在。 物理原理是不会变的。 随着地球变暖, 现在是因为我们排入大气层的多余的二氧化碳, 冰层将会融化, 升温的海洋和融化的冻土 会释放出二氧化碳和甲烷。 虽然我们不知道这些放大的反馈 会多快发生, 但毫无疑问它们会发生, 除非我们停止让地球变暖。 有证据显示 这些反馈已经开始了。 重力卫星GRACE的 精准测量显示, 格陵兰岛和南极都在 变小, 它们每年都会缩小几百立方千米。 自从九年前 测量开始以来, 它们的缩小率都在加快。 甲烷也开始 从冻土中逃出。
What sea level rise can we look forward to? The last time CO2 was 390 ppm, today's value, sea level was higher by at least 15 meters, 50 feet. Where you are sitting now would be under water. Most estimates are that, this century, we will get at least one meter. I think it will be more if we keep burning fossil fuels, perhaps even five meters, which is 18 feet, this century or shortly thereafter.
海平面将会 上升至什么程度? 上一次二氧化碳含量为390ppm时, 这个含量即是现在的含量, 海平面高出了 至少15米,50英尺。 各位现在坐的地方 会在水下。 大多数预算表明,在本世纪, 海平面会上升至少一米。 我认为,如果我们继续燃烧化石燃料, 海平面会上升更多, 在本世纪或此后不久, 海平面也许会上升5米,即18英尺。
The important point is that we will have started a process that is out of humanity's control. Ice sheets would continue to disintegrate for centuries. There would be no stable shoreline. The economic consequences are almost unthinkable. Hundreds of New Orleans-like devastations around the world. What may be more reprehensible, if climate denial continues, is extermination of species. The monarch butterfly could be one of the 20 to 50 percent of all species that the Intergovernmental Panel on Climate Change estimates will be ticketed for extinction by the end of the century if we stay on business-as-usual fossil fuel use.
问题的关键是, 我们将开始一个 超出人类控制的进程。 冰盖将连着几个世纪持续消融。 海岸线将不再稳定。 随之而来的经济损失是不可想象的。 全世界都会出现数百起像新奥尔良一样的 毁灭。 如果我们继续否认气候变化, 更应受谴责的后果恐怕是 物种的灭绝。 据气候变化政府委员会预计, 目前的物种中有百分之二十到五十都会在 本世纪末灭绝, 帝王蝶就可能是 其中之一, 如果我们仍像现在这样使用化石燃料。
Global warming is already affecting people. The Texas, Oklahoma, Mexico heatwave and drought last year, Moscow the year before and Europe in 2003, were all exceptional events, more than three standard deviations outside the norm. Fifty years ago, such anomalies covered only two- to three-tenths of one percent of the land area. In recent years, because of global warming, they now cover about 10 percent -- an increase by a factor of 25 to 50. So we can say with a high degree of confidence that the severe Texas and Moscow heatwaves were not natural; they were caused by global warming. An important impact, if global warming continues, will be on the breadbasket of our nation and the world, the Midwest and Great Plains, which are expected to become prone to extreme droughts, worse than the Dust Bowl, within just a few decades, if we let global warming continue.
全球变暖已经在影响我们了。 去年发生在德州、俄克拉荷马州和墨西哥的 热潮与干旱, 去年的莫斯科热潮 和2003年的欧洲热潮 都是不正常的现象, 这些事情的概率超过了正常值3个标准差。 50年前, 这些异常现象仅 覆盖了百分之一的陆地面积的 十分之二到十分之三。 在近几年, 因为全球变暖, 异常现象覆盖了约百分之十—— 比以前增加了25到50倍。 我们可以很肯定地说, 发生在德州和莫斯科的严重热潮 是反自然的; 它们是由全球变暖造成的。 如果全球变暖持续, 我们以及全世界的食物 都将受到重要影响。 中西部和大平原地区 将变得极易干旱, 比20世纪30年代的大沙尘暴还要严重。 如果我们继续对全球变暖不闻不问, 这将在几十年内就变成事实。
How did I get dragged deeper and deeper into an attempt to communicate, giving talks in 10 countries, getting arrested, burning up the vacation time that I had accumulated over 30 years? More grandchildren helped me along. Jake is a super-positive, enthusiastic boy. Here at age two and a half years, he thinks he can protect his two and a half-day-old little sister. It would be immoral to leave these young people with a climate system spiraling out of control.
我是如何变得越来越 渴望与公众交流, 在10个国家演讲,被逮捕, 耗尽我积攒了30多年的 度假时间? 我的孙子孙女中也有越来越多的人来帮我。 Jake是一个非常积极向上、 热情活跃的男孩儿。 他只有2岁半的时候, 就觉得他能保护 他两岁半天大的妹妹。 把一个持续迅速失控的 气候系统 留给这些年轻人 是不道德的。
Now the tragedy about climate change is that we can solve it with a simple, honest approach of a gradually rising carbon fee collected from fossil fuel companies and distributed 100 percent electronically every month to all legal residents on a per capita basis, with the government not keeping one dime. Most people would get more in the monthly dividend than they'd pay in increased prices. This fee and dividend would stimulate the economy and innovations, creating millions of jobs. It is the principal requirement for moving us rapidly to a clean energy future.
而气候变化的悲剧是, 我们其实只用一个简单、诚实的办法 就可以解决它。 我们可以逐步提高从化石燃料公司 收取的碳化气体排放费, 通过电汇、依据个人收入水平 把这次钱百分之百地分配到 合法居民头上, 政府不拿其中一分钱。 大多数人拿到的月津贴将比 他们为上涨的物价多付的钱要多。 这笔费用和津贴 将促进经济 和创新, 创造数以百万的工作机会。 这是让我们 加速进入一个清洁未来的 主要条件。
Several top economists are coauthors on this proposition. Jim DiPeso of Republicans for Environmental Protection describes it thusly: "Transparent. Market-based. Does not enlarge government. Leaves energy decisions to individual choices. Sounds like a conservative climate plan."
几位顶级经济学家 合作提出这个主张。 来自环保共和党人的Jim DiPeso 因此这样形容道: ”公开透明。以市场需求为基础。 不扩大政府。 让公民个人为能源做决定。 听起来像是一个保守的气候计划。“
But instead of placing a rising fee on carbon emissions to make fossil fuels pay their true cost to society, our governments are forcing the public to subsidize fossil fuels by 400 to 500 billion dollars per year worldwide, thus encouraging extraction of every fossil fuel -- mountaintop removal, longwall mining, fracking, tar sands, tar shale, deep ocean Arctic drilling. This path, if continued, guarantees that we will pass tipping points leading to ice sheet disintegration that will accelerate out of control of future generations. A large fraction of species will be committed to extinction. And increasing intensity of droughts and floods will severely impact breadbaskets of the world, causing massive famines and economic decline. Imagine a giant asteroid on a direct collision course with Earth.
但是政府却没有提高碳化气体排放费, 让化石燃料公司为它们带给社会的 真正危害买单, 却在迫使世界范围的 公民大众每年掏出 400到500亿美元 补贴化石燃料公司。 这就鼓励化石燃料公司去挖掘每一滴化石燃料—— 切掉山顶, 长壁开采,水力压裂, 焦油沙,焦油页岩, 深海北极钻探。 如果我们继续走这条道路, 我们一定会超过引爆点, 引发冰盖消融, 等到了我们的后代时,消融会超出人类控制地加速。 许多物种都将 走向灭亡。 加剧的旱灾和洪涝 将严重影响世界的食物产量, 带来严重的饥荒 和经济衰退。 想象一个巨大的小行星 在和地球正面相撞的轨道上。
That is the equivalent of what we face now. Yet, we dither, taking no action to divert the asteroid, even though the longer we wait, the more difficult and expensive it becomes. If we had started in 2005, it would have required emission reductions of three percent per year to restore planetary energy balance and stabilize climate this century. If we start next year, it is six percent per year. If we wait 10 years, it is 15 percent per year -- extremely difficult and expensive, perhaps impossible. But we aren't even starting.
这和我们现在 所面对的情况是相同的。 然而,我们犹豫不决, 却不改变 小行星的轨道, 即使我们知道我们等得越久, 改变就变得更难更贵。 如果我们从2005年就开始改变的话, 我们需要每年减少百分之三的气体排放, 才能在本世纪重造能源平衡, 稳定气候。 如果我们从明年开始, 我们需要每年减少百分之六。 如果我们等上十年,就得百分之十五—— 极其困难与昂贵, 也许甚至会是不可能的。 然而我们到现在都没有开始。
So now you know what I know that is moving me to sound this alarm. Clearly, I haven't gotten this message across. The science is clear. I need your help to communicate the gravity and the urgency of this situation and its solutions more effectively. We owe it to our children and grandchildren.
现在你们知道了到底是什么 驱使我发出警告。 显然,这个消息还没有被足够广泛地传播。 科学证据再清晰不过了。 我需要你们的帮助, 来更有效地传播 情况的重要性 和紧急性, 以及解决办法。 我们要对我们的后代负责。
Thank you.
谢谢大家。
(Applause)
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