一、全球正在变暖，危机从何而来？
1. Climate change? Global warming? What do we call it?
Both are accurate, but they mean different things.
问题1：“气候变化”还是“全球变暖”？我们应该怎样称呼它？
这两种说法都正确，但含义略有区别。
You can think of global warming as one type of climate change. The broader term covers changes beyond warmer temperatures, such as shifting rainfall patterns. President Trump has claimed that scientists stopped referring to global warming and started calling it climate change because “the weather has been so cold” in winter. But the claim is false. Scientists have used both terms for decades.
“全球变暖”可以视为“气候变化”的一种类型。也就是说，“气候变化”不仅仅包含气温升高，也包括降雨模式上的改变。特朗普先前声称，科学家们不再使用“全球变暖”一词而改用“气候变化”，是因为这根本就是一场骗局，“冬天天气明明那么冷”。他的言论完全错误，几十年来，“全球变暖”和“气候变化”这两个词科学家们都有使用。
2. How much is the Earth heating up?
Two degrees is more significant than it sounds.
问题2：全球变暖的程度到底有多严重？
2华氏度实际上比它听起来要可怕得多。
As of early 2017, the Earth had warmed by roughly 2 degrees Fahrenheit (more than 1 degree Celsius) since 1880, when records began at a global scale. The number may sound low, but as an average over the surface of an entire planet, it is actually high, which explains why much of the world’s land ice is starting to melt and the oceans are rising at an accelerating pace. If greenhouse gas emissions continue unchecked, scientists say, the global warming could ultimately exceed 8 degrees Fahrenheit, which would undermine the planet’s capacity to support a large human population.
自1880年开始有全球范围的气温记录以来，截至2017年初，地球温度平均上升了大约2华氏度(1.12摄氏度)。这一数字也许听上去并不算高，但是作为整个地球表面升温的平均值来说，2华氏度实际上已经很高了。这导致了世界上很多大陆冰层开始融化，海平面上升的速度也在加快。科学家们警告说，如果温室气体的排放迟迟得不到控制，最终全球可能将升温8华氏度，将大大削弱地球的人口承载能力。
3. What is the greenhouse effect, and how does it cause global warming?
We’ve known about it for more than a century. Really.
问题3：什么是温室气体，它又是如何造成全球变暖的？
说真的，一百多年前人们就认识这个概念了。
In the 19th century, scientists discovered that certain gases in the air trap and slow down heat that would otherwise escape to space. Carbon dioxide is a major player; without any of it in the air, the Earth would be a frozen wasteland. The first prediction that the planet would warm as humans released more of the gas was made in 1896. The gas has increased 43 percent above the pre-industrial level so far, and the Earth has warmed by roughly the amount that scientists predicted it would.
在十九世纪，科学家们发现大气中存在几种特定的气体——主要是二氧化碳，这些气体会阻拦并减慢地球表面的热量向外层空间扩散的速度，如果大气中不存在这种气体的话，地球就会变成冰冷的荒漠。1896年，首次有人预言如果人类向大气中排放的温室气体增加，地球的温度将会升高。到目前为止，大气中的温室气体含量相较于工业革命前已经提高了约43%，全球变暖的幅度与科学家们的预测大致相符。
4. How do we know humans are responsible for the increase in carbon dioxide?
This one is nailed down.
问题4：我们怎么知道人类应该为二氧化碳的增加负责？
这是不容否认的事实。
Hard evidence, including studies that use radioactivity to distinguish industrial emissions from natural emissions, shows that the extra gas is coming from human activity. Carbon dioxide levels rose and fell naturally in the long-ago past, but those changes took thousands of years. Geologists say that humans are now pumping the gas into the air much faster than nature has ever done.
科学家们使用放射性同位素示踪法追踪了二氧化碳的来源，区分出了工业排放的二氧化碳和自然界中排放的二氧化碳，这些确凿证据表明：是人类的活动导致了此类气体额外增加。的确，在很久以前二氧化碳的含量会有自然的波动，但这些变化需要数千年的时间才能明显显现。地质学家说，人类现在向大气中排放二氧化碳的速度比自然界任何时候都要更快。
5. Could natural factors be the cause of the warming?
Nope.
问题5：自然因素有可能导致全球变暖吗？
并不会。
In theory, they could be. If the sun were to start putting out more radiation, for instance, that would definitely warm the Earth. But scientists have looked carefully at the natural factors known to influence planetary temperature and found that they are not changing nearly enough. The warming is extremely rapid on the geologic time scale, and no other factor can explain it as well as human emissions of greenhouse gases.
尽管从理论上来说有可能，比如，如果太阳的辐射水平开始升高，那肯定会使地球变暖。但是科学家们已经详细研究了影响行星温度的已知自然因素，这些因素所产生的影响远远不能解释如今的状况。在地质时间的尺度上，现今的气候变暖速度非常快，没有其他的原因能比“人类排放了过多温室气体”更有力解释这一现象。
6. Why do people deny the science of climate change?
Mostly because of ideology.
问题6：为什么人们否认气候变化的科学研究？
主要是因为意识形态的立场。
Instead of negotiating over climate change policies and trying to make them more market-oriented, some political conservatives have taken the approach of blocking them by trying to undermine the science.
一些保守派政治家不想在气候变化政策上进行谈判，也不想驱动市场来解决这些问题，反之，他们试图转而解决提出这些问题的人——通过中伤这些科学研究来阻挠政策谈判的进行。
President Trump has sometimes claimed that scientists are engaged in a worldwide hoax to fool the public, or that global warming was invented by China to disable American industry. The climate denialists’ arguments have become so strained that even oil and coal companies have distanced themselves publicly, though some still help to finance the campaigns of politicians who espouse such views.
特朗普有时会声称科学家们参与了一个全球性的骗局来愚弄大众，或者表示全球变暖是中国为了瘫痪美国的工业而制造的骗局。否认气候变化的人们已经变得如此极端，以至于一些石油和煤炭公司都公开与他们保持距离，尽管还有一些公司依然在支持此类政客的竞选活动。
二、这场危机，谁也无法置身事外
7. How much trouble are we in?
Big trouble.
问题7：我们现在面临的麻烦有多大？
这可是个大麻烦。
Over the coming 25 or 30 years, scientists say, the climate is likely to gradually warm, with more extreme weather. Coral reefs and other sensitive habitats are already starting to die. Longer term, if emissions rise unchecked, scientists fear climate effects so severe that they might destabilize governments, produce waves of refugees, precipitate the sixth mass extinction of plants and animals in the Earth’s history, and melt the polar ice caps, causing the seas to rise high enough to flood most of the world’s coastal cities. The emissions that create those risks are happening now, raising deep moral questions for our generation.
科学家预测，在未来的25年或30年里，气候可能会逐渐变暖，出现更多极端天气。珊瑚礁以及其他一些海洋生物的敏感栖息地已经开始死亡。从长远来看，如果排放量不受控制地增加，科学家们担心如此严重的气候影响，可能会破坏政府稳定，导致难民潮，造成地球历史上第六次动植物大灭绝，并融化极地冰盖，导致海平面上升到足以淹没世界上大多数沿海城市的水平。尽管可能面临巨大风险，人类目前仍然在过度排放，这是我们这代人必须要面对的深刻的道德问题。
8. How much should I worry about climate change affecting me directly?
Are you rich enough to shield your descendants?
问题8：气候变化会直接影响到我吗？我该作何打算？
你有足够的财富来保护你的后代吗？
The simple reality is that people are already feeling the effects, whether they know it or not. Because of sea level rise, for instance, some 83,000 more residents of New York and New Jersey were flooded during Hurricane Sandy than would have been the case in a stable climate, scientists have calculated. Tens of thousands of people are already dying in heat waves made worse by global warming. The refugee flows that have destabilized politics around the world have been traced in part to climate change. Of course, as with almost all other social problems, poor people will be hit first and hardest.
事实告诉我们，不管是否意识到，人类已经受到了气候的影响。例如，据科学家计算，由于海平面上升，在飓风桑迪期间，纽约和新泽西州的居民被洪水淹没的人数比在稳定气候条件下多8.3万人。成千上万的人已经在全球变暖加剧的热浪中死去。造成世界政治不稳定的难民潮在一定程度上归因于气候变化。当然，与其他社会问题一样，穷人受到的打击最大。
9. How much will the seas rise?
The real question is how fast.
问题9：海平面会上升多少？
真正的问题是上升的速度有多快。
The ocean has accelerated and is now rising at a rate of about a foot per century, forcing governments and property owners to spend tens of billions of dollars fighting coastal erosion. But if that rate continued, it would probably be manageable, experts say.
海平面上升正在加速，现在正以每世纪一英尺（约0.3米）的速度上升，这迫使政府和财产所有者花费数百亿美元对抗海岸侵蚀。但专家们表示，如果这个上升速度继续下去，可能结果仍然可控。
The risk is that the rate will increase still more. Scientists who study the Earth’s history say waters could rise by a foot per decade in a worst-case scenario, though that looks unlikely. Many experts believe that even if emissions stopped tomorrow, 15 or 20 feet of sea level rise is already inevitable, enough to flood many cities unless trillions of dollars are spent protecting them. How long it will take is unclear. But if emissions continue apace, the ultimate rise could be 80 or 100 feet.
真正的风险在于上升速度还会进一步加快。研究地球历史的科学家说，在最坏的情况下，海水可能每十年上升一英尺，尽管这看起来不太可能。许多专家认为，即使明天停止排放，海平面上升15或20英尺已经是不可避免的，除非花费数万亿美元采取保护措施，否则这足以淹没许多城市。需要多长时间还不清楚，但如果排放量继续快速增长，最终海平面上升幅度也可能达到80或100英尺。
10. Is recent crazy weather tied to climate change?
Some of it is.
问题10：最近的极端天气是否与气候变化有关？
有些是的。
Scientists have published strong evidence that the warming climate is making heat waves more frequent and intense. It is also causing heavier rainstorms, and coastal flooding is getting worse as the oceans rise because of human emissions. Global warming has intensified droughts in regions like the Middle East, and it may have strengthened a recent drought in California.
科学家们发表了强有力的证据，证明气候变暖使热浪变得更加频繁和强烈。它还造成了更大的暴雨，由于排放量的增加，沿海地区的洪水也变得越来越严重。全球变暖还加剧了中东等地区的干旱，可能也加剧了加州近期的旱情。
In many other cases, though — hurricanes, for example — the linkage to global warming for particular trends is uncertain or disputed. Scientists are gradually improving their understanding as computer analyses of the climate grow more powerful.
不过，其他的一些情况——例如飓风——与全球变暖之间是否有联系尚不确定或者是仍有争议。随着计算机的分析能力越来越强大，科学家们也在逐渐提高他们对极端天气的认识。
三、点点滴滴，化解危机
11. Are there any realistic solutions to the problem?
Yes, but change is happening too slowly.
问题11：有没有什么实际的解决办法？
办法是有的，但是见效会很慢。
Society has put off action for so long that the risks are now severe, scientists say. But as long as there are still unburned fossil fuels in the ground, it is not too late to act. The warming will slow to a potentially manageable pace only when human emissions are reduced to zero. The good news is that they are now falling in many countries as a result of programs like fuel-economy standards for cars, stricter building codes and emissions limits for power plants. But experts say the energy transition needs to speed up drastically to head off the worst effects of climate change.
科学家们说，我们的社会迟迟没有采取行动，导致我们现在面临很严重的风险。但只要地下还有未经开采的化石燃料，那么采取行动还不算太晚。只有实现零碳排放，全球变暖才可能减缓到一个可控的速度。好消息是，由于汽车燃油经济性标准、更严格的建筑规范和发电厂排放限制等项目的实施，许多国家的碳排放正在下降。但专家表示，为了防范气候变化可能带来的最严重的影响，能源转型有必要大幅加快。
12. What is the Paris Agreement?
Virtually every country agreed to limit future emissions.
问题12：《巴黎协定》是什么？
事实上，每个国家都同意限制未来的碳排放。
The landmark deal was reached outside Paris in December 2015. The reductions are voluntary and the pledges do not do enough to head off severe effects. But the agreement is supposed to be reviewed every few years so that countries ramp up their commitments. President Trump announced in 2017 that he would pull the United States out of the deal, though that will take years, and other countries have said they would go forward regardless of American intentions.
2015年12月，这项具有里程碑意义的协定在巴黎的郊外达成。虽然各国的减排目标是自主设定的，而且各国做出的承诺也不足以预防气候变化的严重后果，但是每隔几年人们就会重新审核协定内容，以确保各个国家加大承诺力度。2017年，特朗普宣布美国将退出《巴黎协定》，其他国家表示，无论美国意向如何，他们将继续落实并推进《巴黎协定》。
13. Does clean energy help or hurt the economy?
Job growth in renewable energy is strong.
问题13：清洁能源是经济发展的动力还是阻力？
新能源将会极大增加就业岗位。
The energy sources with the lowest emissions include wind turbines, solar panels, hydroelectric dams and nuclear power stations. Power plants burning natural gas also produce fewer emissions than those burning coal. Converting to these cleaner sources may be somewhat costlier in the short term, but they could ultimately pay for themselves by heading off climate damages and reducing health problems associated with dirty air. And expansion of the market is driving down the costs of renewable energy so fast that it may ultimately beat dirty energy on price alone — it already does in some areas.
风力发电、太阳能发电、水电、核电的碳排放是最低的，此外，与燃煤发电相比，燃气发电的碳排放要更少一些。短期内，改用这些更清洁的能源可能会付出更高的成本，但使用清洁能源可以预防气候变化带来的损失，减少空气污染造成的健康问题，最终收回成本。此外，由于市场不断扩大，清洁能源的成本也在飞速下降，最终，传统能源的价格优势可能也不复存在。在一些地区，这样的趋势已初见端倪。
The transition to cleaner energy certainly produces losers, like coal companies, but it also creates jobs. The solar industry in the United States now employs more than twice as many people as coal mining.
在向清洁能源转型的过程中，部分群体的利益肯定难免受损，比如煤炭公司，但同时，清洁能源的推广也创造了无数就业机会。美国的太阳能行业现在雇佣的员工是煤矿行业的两倍多。
14. What about fracking or ‘clean coal’?
Both could help clean up the energy system.
问题14：“水力压裂技术”和“清洁煤”的效果如何？
这两项技术都有助于推进能源系统清洁化。
Hydraulic fracturing, or “fracking,” is one of a set of drilling technologies that has helped produce a new abundance of natural gas in the United States and some other countries. Burning gas instead of coal in power plants reduces emissions in the short run, though gas is still a fossil fuel and will have to be phased out in the long run. The fracking itself can also create local pollution.
“水力压裂法”是一种钻井技术，这项技术帮助美国以及其他一些国家获得了丰富的天然气资源。尽管用燃气发电来替代燃煤发电可以在短期内减少排放，但天然气仍是一种化石燃料，而且从长远来看将不得不逐步淘汰，此外，“水力压裂”本身也会污染当地环境。
“Clean coal” is an approach in which the emissions from coal-burning power plants would be captured and pumped underground. It has yet to be proven to work economically, but some experts think it could eventually play a major role.
“清洁煤”就是将燃煤发电厂的排放物捕获并泵入地下。这项技术的经济效果还有待验证，但一些专家认为“清洁煤”最终将会发挥重要作用。
15. What’s the latest with electric cars?
Sales are still small overall, but they are rising fast.
问题15：电动汽车行情怎么样？
销售量仍然很小，但增长很快。
They are inherently more efficient than gasoline cars and would represent an advance even if the power were generated by burning coal, but they will be far more important as the electric grid itself becomes greener through renewable power. The cars are improving so fast that some countries are already talking about banning the sale of gasoline cars after 2030.
新能源汽车在本质上比燃油车更有效率，即使电力是由燃煤产生，新能源汽车仍然代表着一种进步。随着供电环节本身因为使用可再生能源而变得更加绿色，新能源汽车未来将变得更为重要。新能源汽车的发展速度如此之快，以至于一些国家已经开始讨论在2030年后禁止销售燃油车。
16. What are carbon taxes, carbon trading and carbon offsets?
It’s just jargon for putting a price on pollution.
问题16：碳排放税、碳交易、碳中和是什么？
这是行业内术语，可以理解为给污染定价。
The greenhouse gases being released by human activity are often called “carbon emissions” for short. That is because two of the most important gases, carbon dioxide and methane, contain carbon. (Some other pollutants are lumped into the same category, even if they do not actually contain carbon.) When you hear about carbon taxes, carbon trading and so on, these are just shorthand descriptions of methods to put a price on emissions, which economists say is one of the most important steps society could take to limit them.
人类活动排放出的温室气体通常简称为“碳排放”，这是因为温室气体中最重要的两种——二氧化碳和甲烷——都含有碳。(其他一些污染物被归为同一类别，但实际上并不含碳。)碳排放税、碳交易之类的术语是对碳排放定价方法的简略描述。经济学家说，这是社会可以采取的限制碳排放的最重要方法之一。
17. Climate change seems so overwhelming. What can I personally do about it?
Start by sharing this with 50 of your friends.
问题17：气候变化似乎很可怕，我个人能做些什么吗？
先把这种观点与50个朋友分享。
Experts say the problem can only be solved by large-scale, collective action. Entire nations have to decide to clean up their energy systems, using every tool available and moving as quickly as they can. So the most important thing you can do is to exercise your rights as a citizen, speaking up and demanding change.
专家称只有大规模的集体行动才能彻底解决气候变化这一问题。各个国家必须利用一切方法，尽快行动起来，推动能源系统清洁化。而个人能做的就是行使好作为公民的权利，呼吁人们重视这一问题，汇聚个人的努力来推进能源的变革。
You can also take direct personal action to reduce your carbon footprint in simple ways that will save you money. You can plug leaks in your home insulation to save power, install a smart thermostat, switch to more efficient light bulbs, turn off unused lights, drive fewer miles by consolidating trips or taking public transit, waste less food, and eat less meat.
你也可以采取更直接的行动，以简单的方式减少你的碳足迹，这还能帮助你节省开支。你可以采用“节能隔热膜”来维持室温，减少空调的使用，也可以安装一个智能恒温器，开灯时要注意切换到更节能的灯泡，记得关掉不用的灯，出门时尽量整合行程或者乘坐公共交通，少吃些肉，不要浪费粮食。
These personal steps may be small in the scheme of things, but they can raise your own consciousness about the problem — and the awareness of the people around you. In fact, discussing this issue with your friends and family is one of the most meaningful things you can do.
这些个人行动可能看起来很微不足道，但正是这样的点点滴滴提升了我们以及周围的人对气候变化这一问题的意识。事实上，与我们的朋友和家人讨论这一问题是我们能做的最有意义的事情之一。
编译 | 高语阳 王兆隆 储志阳
排版 | 储志阳
原文链接：
https://www.nytimes.com/interactive/2017/climate/what-is-climate-change.html