I'm here to talk to you about something important that may be new to you.
我来跟大家聊一聊大家没有听说的重要事情。
The governments of the world are about to conduct an unintentional experiment on our climate.
世界各国政府要对我们的气候做一个实验。
In 2020, new rules will require ships to lower their sulfur emissions by scrubbing their dirty exhaust or switching to cleaner fuels.
2020年，会有新的规则要求船只通过清洁排放废气换用清洁能源来降低硫的排放量。
For human health, this is really good, but sulfur particles in the emission of ships also have an effect on clouds.
对人体健康来说，这是好事，但船只排放的硫粒子对云也会造成影响。
This is a satellite image of marine clouds off the Pacific West Coast of the United States.
这是美国西太平洋沿岸的卫星云图。
The streaks in the clouds are created by the exhaust from ships.
云中的这些条纹就是船只废气造成的。
Ships' emissions include both greenhouse gases, which trap heat over long periods of time,
船只会排放积累了长期热量的温室气体
and particulates like sulfates that mix with clouds and temporarily make them brighter.
以及如硫这样的粒子，它们会和云混在一起短期内让云变得更加明亮。
Brighter clouds reflect more sunlight back to space, cooling the climate.
明亮的云会把更多的阳光反射进太空，让气候变冷。
So in fact, humans are currently running two unintentional experiments on our climate.
所以实际上，人类现在无意中在对我们的气候做两个实验。
In the first one, we're increasing the concentration of greenhouse gases and gradually warming the earth system.
在第一个实验中，我们增加了温室气体的集聚，加热了地球。
This works something like a fever in the human body.
这就像人体的发烧一样。
If the fever remains low, its effects are mild,
如果是低烧，产生的影响就温和，
but as the fever rises, damage grows more severe and eventually devastating. We're seeing a little of this now.
但是如果高烧，破坏就会更严重，甚至是毁灭性的。我们现在已经见证了一小部分了。
In our other experiment, we're planning to remove a layer of particles that brighten clouds and shield us from some of this warming.
在另一个实验中，我们计划把让云层变得明亮以及把我们和热气隔绝开的那层屏障移除。
The effect is strongest in ocean clouds like these,
它的影响对这种海洋上空的云最大，
and scientists expect the reduction of sulfur emissions from ships next year to produce a measurable increase in global warming.
科学家希望明年减少船只的硫排放量以加快全球变暖。
Bit of a shocker? In fact, most emissions contain sulfates that brighten clouds: coal, diesel exhaust, forest fires.
被吓到了吗？实际上，大部分排放物中都包含会让云变亮的硫：如煤炭、柴油废气、森林火灾。
Scientists estimate that the total cooling effect from emission particles, which they call aerosols when they're in the climate,
科学家们预测，被排放出的粒子到了大气中被叫做悬浮微粒，它们产生的冷却效果加起来，
may be as much as all of the warming we've experienced up until now.
可能跟我们现在感受到的温室效应程度差不多。
There's a lot of uncertainty around this effect,
对于这个影响还有很多不确定性，
and it's one of the major reasons why we have difficulty predicting climate,
这也是我们很难预测气候变化的主要原因之一，
but this is cooling that we'll lose as emissions fall.
但随着排放量降低，我们失去的是冷却效果。
So to be clear, humans are currently cooling the planet by dispersing particles into the atmosphere at massive scale.
所以说白了，人类现在正在大量向大气层中释放冷却大气的粒子。
We just don't know how much, and we're doing it accidentally.
只是我们不知道排放了多少，而且这只是偶然发生的。
That's worrying, but it could mean that we have a fast-acting way to reduce warming,
这很令人担心，但它也意味着我们有办法可以快速减轻全球变暖，
emergency medicine for our climate fever if we needed it, and it's a medicine with origins in nature.
它是治疗气候变暖的特效药，而且这个药还来自于自然。
This is a NASA simulation of earth's atmosphere, showing clouds and particles moving over the planet.
这是美国航天局模拟的地球大气层，上面有围绕着地球的云和粒子。
The brightness is the Sun's light reflecting from particles in clouds,
亮的部分就是云中的粒子反射回来的太阳光，
and this reflective shield is one of the primary ways that nature keeps the planet cool enough for humans and all of the life that we know.
就是这个反射层让地球变得凉爽，好让人类和其他我们知道的生命存活。
In 2015, scientists assessed possibilities for rapidly cooling climate.
2015年，科学家评估了气候快速转冷的可能性。
They discounted things like mirrors in space, ping-pong balls in the ocean, plastic sheets on the Arctic,
他们忽视了太空中的镜子，海里的乒乓球和太平洋上的塑料袋，
and they found that the most viable approaches involved slightly increasing this atmospheric reflectivity.
他们发现的最可行的办法就包括稍微增强大气层的反射率。
In fact, it's possible that reflecting just one or two percent more sunlight from the atmosphere
实际上有可能多反射百分之一到百分之二的阳光，
could offset two degrees Celsius or more of warming.
可以抵消两摄氏度或以上的变暖。
Now, I'm a technology executive, not a scientist.
我是一名技术主管，不是科学家。
About a decade ago, concerned about climate, I started to talk with scientists about potential countermeasures to warming.
大约十年前，因为关心气候，我开始与科学家们讨论潜在的应对气候变暖的策略。
These conversations grew into collaborations that became the Marine Cloud Brightening Project,
我们之间的对话逐渐演变成利用海洋给云增亮项目，
which I'll talk about momentarily, and the nonprofit policy organization SilverLining, where I am today.
这点我稍后会说，还有非营利组织银边，也是我现在所在的组织，
I work with politicians, researchers, members of the tech industry and others to talk about some of these ideas.
我跟政治家、研究人员、技术从业者和其他人一起讨论过一些想法。
Early on, I met British atmospheric scientist John Latham,
前期，我见过英国气候科学家约翰·莱瑟姆，
who proposed cooling the climate the way that the ships do, but with a natural source of particles:
他提议过用现在的船的方法来使气候转冷，但是用的却是自然界的粒子：
sea-salt mist from seawater sprayed from ships into areas of susceptible clouds over the ocean.
水里的海盐形成的雾，用船把它们散布到海面上的云层里。
The approach became known by the name I gave it then, "marine cloud brightening."
这个方法因为那时起的名字很出名，叫海洋点亮云层计划。
Early modeling studies suggested that by deploying marine cloud brightening in just 10 to 20 percent of susceptible ocean clouds,
早期的模拟研究表明，在10%到20%的易受影响的海洋云层中部署海洋云层增亮剂，
it might be possible to offset as much as two degrees Celsius's warming.
可能会抵消多达2摄氏度的升温。
It might even be possible to brighten clouds in local regions to reduce the impacts caused by warming ocean surface temperatures.
甚至有可能可以通过把当地的云层变亮，来降低海平面温度上升带来的影响。
For example, regions such as the Gulf Atlantic might be cooled in the months before a hurricane season to reduce the force of storms.
比如，在飓风来临的前几个月给墨西哥湾降温好减轻风暴的强度。
Or, it might be possible to cool waters flowing onto coral reefs overwhelmed by heat stress, like Australia's Great Barrier Reef.
或者，可以降低被热浪影响的流过珊瑚礁的水流的温度，比如澳大利亚的大堡礁。
But these ideas are only theoretical,
但这些想法只是理论上的，
and brightening marine clouds is not the only way to increase the reflection of the sunlight from the atmosphere.
增亮海平面上的云层并不是唯一增强大气层反射太阳光能力的方法。
Another occurs when large volcanoes release material with enough force to reach the upper layer of the atmosphere, the stratosphere.
大型火山喷发时释放出的物质会有足够的能量到达大气层的上一层，平流层。
When Mount Pinatubo erupted in 1991, it released material into the stratosphere,
皮纳图博火山1991年爆发时，释放出的物质进入了平流层，
including sulfates that mix with the atmosphere to reflect sunlight.
其中包含的硫酸盐与大气混合就可以反射日光。
This material remained and circulated around the planet.
这些物质在地球上空徘徊。
It was enough to cool the climate by over half a degree Celsius for about two years.
它足以给大气降温超过0.5摄氏度，时间持续约两年。
This cooling led to a striking increase in Arctic ice cover in 1992,
这种冷却效果导致1992年北极冰川陡然变厚，
which dropped in subsequent years as the particles fell back to earth.
其后几年随着粒子落回地面再次变薄。
But the volcanic phenomenon led Nobel Prize winner Paul Crutzen to propose the idea
但火山喷发的现象给了诺贝尔奖得主保罗·克鲁岑灵感，
that dispersing particles into the stratosphere in a controlled way might be a way to counter global warming.
他提出在可控的前提下给平流层增加粒子数量，可能可以应对全球变暖。
Now, this has risks that we don't understand, including things like heating up the stratosphere or damage to the ozone layer.
这个方法有我们无法理解的风险，包括平流层升温或破坏臭氧层。
Scientists think that there could be safe approaches to this, but is this really where we are?
科学家们认为可能有安全的办法实现这一点，但我们真的只能这样做了吗？
Is this really worth considering?
这个方法真的值得考虑吗？
This is a simulation from the US National Center for Atmospheric Research global climate model showing, earth surface temperatures through 2100.
这是美国国家气候研究中心对全球气候做出的一个模拟，它显示了到2100年气球表面的温度。

The globe on the left visualizes our current trajectory,
左边的球显示了我们目前的状态，
and on the right, a world where particles are introduced into the stratosphere gradually in 2020, and maintained through 2100.
右边的球是我们从2020年开始，往平流层加入粒子并一直持续到2020年的状态。
Intervention keeps surface temperatures near those of today, while without it, temperatures rise well over three degrees.
人为干预使得地球的温度跟现在的接近，而没有加入粒子的话，地球温度会上升超过3摄氏度。
This could be the difference between a safe and an unsafe world.
这就是在安全和不安全世界的区别。
So, if there's even a chance that this could be close to reality, is this something we should consider seriously?
如果有机会把这个想法变成现实，我们应该认真考虑这个方法吗？
Today, there are no capabilities, and scientific knowledge is extremely limited.
今天我们没有能力这样做，科学知识也有限。
We don't know whether these types of interventions are even feasible, or how to characterize their risks.
我们甚至不知道这些人为干预是否可行，它们的风险如何。
Researchers hope to explore some basic questions
研究员们想要搞清楚一些基本的问题，
that might help us know whether or not these might be real options or whether we should rule them out.
好帮我们弄明白这些方法是否真有可行性，还是应该早早把它们剔除掉。
It requires multiple ways of studying the climate system,
它需要我们从各种方面研究气候系统，
including computer models to forecast changes, analytic techniques like machine learning, and many types of observations.
包括用电脑模型预测变化，用分析技术比如机器学习，还有各种观察手段。
And though it's controversial, it's also critical that researchers develop core technologies and perform small-scale, real-world experiments.
尽管存在争议，让研究人员开发核心技术以及进行小规模的实地测试还是很重要的。
There are two research programs proposing experiments like this.
有两个研究机构提出了这样的实验。
At Harvard, the SCoPEx experiment would release very small amounts of sulfates,
在哈佛，SCoPEx实验会用气球向平流层中释放非常少量的硫酸盐、
calcium carbonate and water into the stratosphere with a balloon, to study chemistry and physics effects.
碳酸钙和水，好研究物理和化学影响。
How much material? Less than the amount released in one minute of flight from a commercial aircraft.
释放了多少物质呢？比一架商业航天器一分钟释放的量还少。
So this is definitely not dangerous, and it may not even be scary.
所以这完全不危险，也不会很可怕。
At the University of Washington, scientists hope to spray a fine mist of salt water into clouds in a series of land and ocean tests.
华盛顿大学的科学家想在土地和海洋上空的云层中喷洒一层盐水。
If those are successful, this would culminate in experiments to measurably brighten an area of clouds over the ocean.
如果成功的话，点亮海洋上空的一小块云层的实验将会是无与伦比的。
The marine cloud brightening effort is the first to develop any technology for generating aerosols for atmospheric sunlight reflection in this way.
增亮海洋上空的云是第一个通过增加大气中的悬浮微粒来增强阳光反射的方法。
It requires producing very tiny particles
它要求生产极其微小的粒子，
think about the mist that comes out of an asthma inhaler -- at massive scale
设想一下哮喘喷剂里喷出来的水雾--大规模生产
so think of looking up at a cloud. It's a tricky engineering problem.
想象一下仰望一片云。这是一个棘手的工程问题。
So this one nozzle they developed generates three trillion particles per second,
他们研发的这个喷罐可以一秒喷出3万亿粒子，
80 nanometers in size, from very corrosive saltwater.
每粒只有80纳米，取自腐蚀性极强的盐水。
It was developed by a team of retired engineers in Silicon Valley -- here they are
研发者是硅谷退休的一支工程师团队，
working full-time for six years, without pay, for their grandchildren.
为了他们的孙辈，他们在没有薪水的情况下全职工作了6年。
It will take a few million dollars and another year or two to develop the full spray system they need to do these experiments.
为了做实验，他们还要再花几百万美元和一两年时间研制出完整的喷雾系统。
In other parts of the world, research efforts are emerging,
在世界的其他地方，各种研究机构都在努力，
including small modeling programs at Beijing Normal University in China,
包括中国的北京师范大学的小模型项目，
the Indian Institute of Science, a proposed center for climate repair at Cambridge University in the UK
印度科学研究所，英国剑桥大学的一所气候修复建议中心
and the DECIMALS Fund, which sponsors researchers in global South countries
以及DECIMALS基金，它赞助了南半球的几个国家的研究人员
to study the potential impacts of these sunlight interventions in their part of the world.
去研究这些干预措施对其所在地区的潜在影响。
But all of these programs, including the experimental ones, lack significant funding.
但是所有这些项目，包括正在进行实验的项目，都缺少资金。
And understanding these interventions is a hard problem.
并且要理解透彻这种干预是很困难的。
The earth is a vast, complex system and we need major investments in climate models, observations and basic science
地球是一个巨大的、复杂的系统，我们需要对气候模型、观察过程和基础科学进行大规模的投资，
to be able to predict climate much better than we can today
好让我们能够比今天更好的预测气候，
and manage both our accidental and any intentional interventions. And it could be urgent.
以及管理任何偶然和故意的人为干预。这件事情很紧急。
Recent scientific reports predict that in the next few decades, earth's fever is on a path to devastation:
最近的科学报告预测在接下来的几十年里，地球温度将会达到一个毁灭性的级别：
extreme heat and fires, major loss of ocean life, collapse of Arctic ice,
极度高温和火灾，海洋生物的大量减少，北极冰川崩塌，
displacement and suffering for hundreds of millions of people.
数以亿计的人民流离失所，饱受苦难。
The fever could even reach tipping points where warming takes over
温度一旦上升到顶点，
and human efforts are no longer enough to counter accelerating changes in natural systems.
人类的努力将无法再抵消自然界累积的变化。
To prevent this circumstance, the UN's International Panel on Climate Change predicts
为阻止这些事情的发生，联合国国际气候变化小组预测，
that we need to stop and even reverse emissions by 2050. How?
到2050年我们就要停止甚至逆排放。怎么做到呢？
We have to quickly and radically transform major economic sectors,
我们要立刻改变经济发展方式，
including energy, construction, agriculture, transportation and others.
包括能源、建设、农业、交通和其他方面。
And it is imperative that we do this as fast as we can.
我们必须尽快完成这些事。
But our fever is now so high that climate experts say we also have to remove massive quantities of CO2 from the atmosphere,
但当前地球温度已经很高了，科学家认为我们还必须大量减少大气中二氧化碳的含量，
possibly 10 times all of the world's annual emissions, in ways that aren't proven yet.
可能要减少每年排放量的10倍，而方法还不得而知。
Right now, we have slow-moving solutions to a fast-moving problem.
现在，我们对快速发展的问题有缓慢的解决方案。
Even with the most optimistic assumptions, our exposure to risk in the next 10 to 30 years is unacceptably high, in my opinion.
即使是最积极的假设里，在我看来，我们在接下来10-30年里面临的危机也非常之大。
Could interventions like these provide fast-acting medicine if we need it to reduce the earth's fever while we address its underlying causes?
如果为了降低地球温度，这些干预手段带来了新的副作用，那它们还是好的特效药吗？
There are real concerns about this idea.
这个想法确实令人担忧。
Some people are very worried that even researching these interventions
有些人还担心对这些干预手段的测试，
could provide an excuse to delay efforts to reduce emissions.
会给人们拒绝降低排放量提供借口。
This is also known as a moral hazard.
这也是我们面临的道德危机。
But, like most medicines, interventions are more dangerous the more that you do,
但就像大部分药物一样，干预得越多，越是危险，
so research actually tends to draw out the fact
所以这些实验实际上引出了一个真相，
that we absolutely, positively cannot continue to fill up the atmosphere with greenhouse gases,
我们绝对不能再向大气中排放温室气体，
that these kinds of alternatives are risky and if we were to use them, we would need to use as little as possible.
这些手段有其风险，所以如果要用，我们就需要尽可能的少用。
But even so, could we ever learn enough about these interventions to manage the risk?
但即使如此，我们能否对这些干预措施有足够的了解来控制风险呢？
Who would make decisions about when and how to intervene?
谁来决定何时、怎样进行干预？
What if some people are worse off, or they just think they are?
如果有人的处境更危险，或他们觉得自己的处境更危险了呢？
These are really hard problems. But what really worries me is that
这些问题都很难回答。但真正让我担忧的是，
as climate impacts worsen, leaders will be called on to respond by any means available.
随着气候变化加剧，人们会要求领导人对任何一个方法作出回应。
I for one don't want them to act without real information and much better options.
我个人并不希望他们在没有真实信息和更好的选择的情况下作出回应。
Scientists think it will take a decade of research just to assess these interventions, before we ever were to develop or use them.
科学家认为在研究和使用之前，仅仅评估干预措施的可行性就要花上10年。
Yet today, the global level of investment in these interventions is effectively zero.
而今天，全球范围内对这些干预措施的投资几乎为零。
So, we need to move quickly if we want policymakers to have real information on this kind of emergency medicine.
所以如果要决策者掌握这种特效药的真实信息，我们要更快地行动。
There is hope! The world has solved these kinds of problems before.
我们还有希望！我们解决过这种问题。
In the 1970s, we identified an existential threat to our protective ozone layer.
20世纪70年代，我们发现臭氧层存在威胁。
In the 1980s, scientists, politicians and industry came together in a solution to replace the chemicals causing the problem.
20世纪80年代，科学家、政治家、各行各业的人聚集到一起，想出办法替代了导致这个问题的化学物质。
They achieved this with the only legally binding environmental agreement signed by all countries in the world, the Montreal Protocol.
世界上全部国家签署了唯一一个合法的环保协定，蒙特利尔协议。
Still in force today, it has resulted in a recovery of the ozone layer
它到今天依然有效，臭氧层恢复了，
and is the most successful environmental protection effort in human history.
它也是人类历史上最成功的环保政策。
We have a far greater threat now,
我们现在面临着更大的威胁，
but we do have the ability to develop and agree on solutions to protect people and restore our climate to health.
但我们有研发能力，也可以想出办法保护全人类，让气候变得健康。
This could mean that to remain safe, we reflect sunlight for a few decades, while we green our industries and remove CO2.
这可能意味着，为了保持安全，我们要在未来几十年里反射日光，同时绿化我们的工业，消除二氧化碳。
It definitely means we must work now to understand our options for this kind of emergency medicine. Thank you.
这无疑意味着我们必须现在就努力理解这种特效药。谢谢大家。