Geoengineering still faces major practical challenges
Geoengineering still faces major practical challenges
地球工程仍面临重大的现实挑战
EXECUTIVE SUMMARY Solar geoengineering is often portrayed as a sort of emergency brake. Something along the lines of “Pull in case of climate emergency” to scatter light-reflecting particles to bounce sunlight out of the atmosphere and cool the planet. But it might be less like a simple brake and more like a complicated, entirely unsolved puzzle. Some researchers are starting to look into how nations or companies would go about trying to cool the planet—and there’s a lot to figure out. My colleague James Temple dug into these engineering challenges in his latest feature story. My biggest takeaway? This all might be a lot harder than I thought.
执行摘要 太阳地球工程常被比作一种“紧急制动器”。它类似于“气候紧急情况下拉动”的装置，通过散布反射光线的颗粒，将阳光反射出大气层以冷却地球。但它可能并不像一个简单的刹车，而更像是一个复杂且完全未解的谜题。一些研究人员正开始探索各国或企业将如何尝试冷却地球——而这其中有太多问题需要解决。我的同事詹姆斯·坦普尔（James Temple）在他最新的专题报道中深入探讨了这些工程挑战。我最大的感触是：这一切可能比我想象的要困难得多。
I’ll admit, I’ve always thought of geoengineering as a relatively low-tech solution. That’s partly because over the years we’ve seen some companies do their own low-cost guerrilla “experiments,” tossing balloons up into the atmosphere and claiming to have made some small dent in climate change. But to actually actively cool the planet in a significant way, and to make sure we understand exactly what effect we’re having, there’s a lot that researchers still need to learn.
我承认，我一直认为地球工程是一种相对低技术的解决方案。部分原因是多年来我们看到一些公司在进行自己的低成本“游击式实验”，将气球扔进大气层，并声称对缓解气候变化产生了一些微小的影响。但要真正以显著方式主动冷却地球，并确保我们准确了解所产生的影响，研究人员仍有许多东西需要学习。
First, there’s the problem of getting up into the atmosphere. Generally, the target for solar geoengineering efforts is the stratosphere, since the air there is drier and more stable, so particles deposited there would stay aloft and move around the planet, lowering temperatures over a wider area and for a longer time. You can release the particles in balloons, but balloons may not go where you want them to. And at a large scale, you’d be leaving a lot of litter all over the planet. That leaves aircraft, but conventional planes aren’t suited to fly around in the stratosphere. (Commercial aircraft generally fly at around 12 kilometers above the Earth’s surface, while geoengineering would require reaching roughly 20 kilometers.)
首先是进入大气层的问题。通常，太阳地球工程的目标是平流层，因为那里的空气更干燥、更稳定，沉积在那里的颗粒可以保持悬浮并环绕地球移动，从而在更大范围和更长时间内降低温度。你可以用气球释放这些颗粒，但气球可能无法到达你想要的位置。而且在大规模操作下，你会在全球各地留下大量垃圾。剩下的选择是飞机，但传统飞机并不适合在平流层飞行。（商用飞机通常在距离地表约12公里的高度飞行，而地球工程则需要达到约20公里的高度。）
The air is thinner higher up, so aircraft with massive wings would probably fare better than more conventional designs. One design, from a startup called Iris Aero, shows just how much rethinking of our current flight technologies might be needed—the plane is almost unsettling in its proportions. Its wings are so long, on a stubby little body. It reminds me of a water strider, those bugs that have super-long legs to scurry around on a pond’s surface.
高空空气稀薄，因此拥有巨大机翼的飞机可能比传统设计表现更好。一家名为 Iris Aero 的初创公司提出的一种设计，展示了我们对现有飞行技术可能需要进行多大程度的重新思考——这架飞机的比例几乎让人感到不安。它有着长长的机翼，却配着一个短粗的机身。这让我想起了水黾，那种长着超长腿在池塘表面疾走的小虫子。
And that’s just the beginning. There’s also the question of what, exactly, would be best to scatter up in the stratosphere. The idea behind geoengineering comes from volcanoes—after an eruption, sulfuric acid ends up floating around in the atmosphere, and it can temporarily cool the planet. But that chemical is sticky and would be heavy to carry, so scattering some sort of precursor to sulfuric acid would probably be better. Researchers, including some at the University of Chicago, one of the leading institutions in this field, are working to figure out the best formula.
而这仅仅是个开始。还有一个问题是，究竟散布什么物质到平流层效果最好。地球工程背后的灵感来自火山——火山喷发后，硫酸会漂浮在大气中，可以暂时冷却地球。但这种化学物质具有粘性且携带沉重，因此散布某种硫酸前体可能更好。包括芝加哥大学（该领域领先机构之一）在内的研究人员，正在努力寻找最佳配方。
I’m struck by how complicated this turns out to be, and I’m also left with a big question: As research turns from modeling and simulations to the practical aspects of this incredibly controversial technology, what does it mean to be doing this work? There are major concerns about what effects might come from large-scale attempts to cool the planet. The effects could be positive for some parts of the globe and negative for others. Established weather patterns, like the monsoon season in South Asia, could shift. There are major questions about what the governance for the use of geoengineering should look like, and who gets to decide whether to go ahead.
我被这项技术的复杂性所震撼，同时也留下了一个巨大的疑问：当研究从建模和模拟转向这项极具争议技术的实际应用层面时，开展这项工作意味着什么？人们对大规模冷却地球的尝试可能带来的影响深感担忧。这些影响对全球某些地区可能是积极的，而对其他地区则可能是负面的。既定的天气模式，如南亚的季风季节，可能会发生改变。关于地球工程的治理应采取何种形式，以及由谁来决定是否推进，都存在重大疑问。
Experts who champion research in geoengineering often draw a line between a desire to support learning more about the technology and a call to deploy it. Many would argue that we should understand it better, so we can make informed decisions. But to me, there’s a clear difference between atmospheric modeling and detailed engineering work on an aircraft. If there’s public research that essentially amounts to a set of practical instructions, I can’t help but feel like it could enable any number of individual actors or nations to take geoengineering into their own hands. It also might normalize the idea of using the technology.
支持地球工程研究的专家通常会将“支持深入了解该技术”与“呼吁部署该技术”划清界限。许多人认为我们应该更好地了解它，以便做出明智的决策。但在我看来，大气建模与详细的飞机工程工作之间有着明显的区别。如果公开的研究本质上是一套实用指南，我不禁担心这可能会使任何个人行为者或国家能够自行实施地球工程。这也可能会使使用该技术的想法变得常态化。
Some experts shared concerns along these lines with James, arguing that the shift to practical engineering work requires more oversight. Some called research in this area dangerous. One alternative perspective I found interesting came from Shuchi Talati, executive director of the nonprofit Alliance for Just Deliberation on Solar Geoengineering. Rather than further practical research making a slippery slope slipperier, it could have the opposite effect, she told James. “The actual practice of R&D will be a sticky slope, because there will be more real-world problems that come up that we haven’t even thought of yet,” she says. Engineering research could challenge the “idealized notions” of how easy the technology would actually be, she adds.
一些专家向詹姆斯表达了类似的担忧，认为转向实际工程工作需要更多的监管。有些人甚至称该领域的研究是危险的。我发现非营利组织“太阳地球工程公正审议联盟”（Alliance for Just Deliberation on Solar Geoengineering）执行董事舒奇·塔拉蒂（Shuchi Talati）提出了一个有趣的替代观点。她告诉詹姆斯，进一步的实际研究不仅不会让“滑坡效应”变得更严重，反而可能产生相反的效果。“研发的实际操作将是一个‘粘性斜坡’，因为会出现更多我们甚至还没想到的现实世界问题，”她说。她补充道，工程研究可能会挑战人们对于该技术“实际上有多容易”的理想化观念。
It’s hard to argue against better understanding potential tools to address climate change. But if we draw a map towards a potential future, it might become difficult to control who follows it.
很难反对去更好地了解应对气候变化的潜在工具。但如果我们绘制了一张通往未来可能性的地图，那么控制谁会跟随这张地图前进，可能会变得非常困难。