《大西洋月刊》：当一场致命的气候灾难袭击全球海洋时 [美国媒体]

When a Killer ClimateCatastrophe Struck the World's Oceans

当一场致命的气候灾难袭击全球海洋时



Identifying a killer can be difficult when it seemslike every murder weapon imaginable has been used in the crime, and when thevictim is the entire planet. About 252 million years ago, a rich and wonderfulworld was annihilated in the worst mass extinction ever: the end-Permian, acatastrophe with no close competitor in Earth’s history. Volcanoes of a trulypreposterous scale erupted in Siberia over many thousands of years, loosing allmanner of chaos on the world. Rounding up, everything died.

当所有可以想象得到的致命武器似乎都被用于犯罪时，当受害者是整个星球时，识别杀手可能会很困难。大约2亿5千2百万年前，一个富饶而美好的世界在有史以来最严重的物种大灭绝中覆没了：它发生在二叠纪末期，是一场在地球历史上最为严重的大灾难。在西伯利亚，几千年的时间里发生了一场真正可以说是规模反常的火山爆发，给世界带来了各种各样的混乱。最后，一切都陷入了死寂当中。



“I think this study shows the end of the road that we’re headingdown,” says the lead author, Justin Penn of the University of Washington, aboutour modern, warming, and increasingly suffocating oceans.

“我认为这项研究表明了我们前进道路的尽头，”研究报告的主要作者、华盛顿大学的贾斯汀·佩恩在谈到我们现代的正在变暖并且越来越令人窒息的海洋时这么说道。

As we’ve known since the 1860s, carbon dioxide is avery important greenhouse gas, and if you increase the amount of it in theatmosphere, it makes the planet warmer. At the end of the Permian, thevolcanoes of Siberia, by burning through a giant basin filled with coal andother carbon-rich rocks, emitted enough carbon dioxide to warm the planet by asweltering 10 degrees Celsius or so. Coincidentally, this is about the samemagnitude of warming predicted for humanity in a modern burn-it-all scenario.

我们自19世纪60年代开始就知道，二氧化碳是一种非常重要的温室气体，如果你增加它在大气中的含量，它就会使地球变暖。在二叠纪末期，西伯利亚的火山通过燃烧一个巨大的盆地——这个盆地充满了煤和其他富含碳的岩石——释放出的二氧化碳足以使地球变暖10摄氏度左右。无巧不成书的是，在现代“焚尽所有”的场景下，它与人类预测到的变暖幅度是大致相同的。

“If we are truly the stupidest intelligent species ever, we probablycould do the same thing,” says Curtis Deutsch, a co-author on the study. “As itis, we’re headed toward 3 to 4 degrees Celsius of warming by the end of thecentury, which is nothing to sniff at. But 10 degrees isn’t that off thecharts.”

“如果我们真的是有史以来最愚蠢的聪明物种，我们可能会做同样的事情，”这项研究的合着者之一柯蒂斯·多伊奇说道，“事实上，到本世纪末，我们将面临3到4摄氏度的升温幅度，这没什么大不了的。但10度也不算离谱”。



By jacking up the CO2 in their model high enough,Penn and his colleagues were able to re-create the scorching temperatures ofthe end-Permian mass extinction, searing their ancient climate model maps inworrying shades of red. The flip side of a hot ocean is one with less oxygen,and it has long been known that the oceans of the end-Permian were gasping forthe stuff. This paleoceanographic fact has been uncovered by geologists whohave found the sickly presence of laminated, pyrite-rich ocean rocks inend-Permian rock outcrops around the word—from the Salt Range in Pakistan tothe old whaling redoubt of Spitsbergen in the Arctic Ocean. Even subtler,uranium isotopes in rocks from the catastrophe whisper dark rumors about theasphyxiation of the entire ancient ocean.

佩恩和他的同事们通过将模型中的二氧化碳提升到足够高的浓度，重新创造出了二叠纪末期大灭绝时的灼热温度，在这个模型中，令人担忧的红色阴影炙烤着他们的古老气候模型地图。高温海洋的另一面是含氧量变得更少，而二叠纪末期的海洋一直渴望得到这种物质，这一点早已为人所知。地质学家们已经发现了这一古海洋学事实，他们在世界各地的二叠纪末期露出地表的岩石——从巴基斯坦的盐层到北冰洋斯匹次卑尔根的捕鲸堡垒——中发现了层状的富含黄铁矿的海洋岩石。甚至更微妙的是，灾难中岩石中的铀同位素也在散布着关于整个古代海洋被窒息的黑暗谣言。

By driving up the temperature in his model, Pennre-created this end-Permian oxygen loss as well. This is because oxygen is lesssoluble in hot water, so heat alone can cause oxygen to plummet in the ocean.But a hotter ocean is also a more sluggish and stratified one, so the depthsbecome starved of oxygen’s delivery as well. Even worse, the hotter it gets,the more oxygen animals need to power their metabolism, so hot water quicklycreates a crisis of supply and demand. By populating his model ancient oceanwith modern creatures, such as sharks and crabs and corals—creatures with avariety of tolerances to things like deoxygenation, temperature, and pH—andthen letting all climate hell break loose, Penn found that it was theheat-driven loss of oxygen in the ocean, more than any other factor, that couldexplain the end of the world.

通过在他的模型中提高温度，佩恩也重构了二叠纪末期的氧气损失情况。这是因为氧气在热水中溶解性较差，因此仅凭热量就能使氧气在海洋中的浓度急剧下降。但是一个更热的海洋也是一个流动更慢和分层了的的海洋，所以深海也变得缺氧了。更糟糕的是，温度越高，动物新陈代谢所需的氧气就越多，因此热水很快就会造成供需危机。通过将现代海洋生物——如鲨鱼、螃蟹和珊瑚——也就是对于脱氧环境、温度和酸度有着不同耐受度的生物放入这一古代海洋模型中，然后让所有的气候地狱挣脱牢笼，佩恩发现海洋中，温度升高所驱动的氧气损失比任何其他因素更能够解释这个世界末日。



“This study suggests we should be worrying much more about hypoxiathan about ocean acidification,” Deutsch says. “There’s vastly more resourcesbeing put into [studying] organisms’ responses to pH in seawater than there isinto understanding temperature-dependent hypoxia. I think that the field hasbasically allocated those resources in exactly the wrong way.”

多伊奇说：“这项研究表明，我们应该更多地担心缺氧的情况，而不是海洋酸化。人们投入(研究)生物对海水酸性的反应的资源要远远多于投入理解取决于温度的缺氧情况的资源。我认为，该领域基本上是以一种完全错误的方式分配了这些资源”。

The modern oceans have already lost 2 percent oftheir oxygen since 1960, a remarkable loss driven mostly by coastal nutrientpollution and global warming. It’s an environmental problem that promises toworsen in the warmer world of the coming centuries, just like it did in theend-Permian. And if Earth’s past is any indication of its future, thisasphyxiation could be truly world changing. The prospect has led dozens ofpaleoclimatologists, geochemists, and oceanographers to sign the KielDeclaration on Ocean Deoxygenation, developed this September to raise globalawareness of a problem with increasingly worrying geological precedent.

自1960年以来，现代海洋已经失去了2%的氧气，这一显着损失主要是由沿海营养污染和全球变暖造成的。就像二叠纪末期一样，在未来几个世纪气候变暖的世界里，这一环境问题注定会趋于恶化。如果地球的过去能预示它的未来，那么这种窒息可能会真正改变世界。这一前景促使数十名古气候学家、地球化学家和海洋学家签署了《基尔海洋脱氧宣言》。该宣言于今年9月制定，旨在提高全球对这个日益令人担忧的地质先例问题的认识。

“This study shows that we’re on that same road toward extinction, andthe question is how far down it we go,” Penn says.

佩恩说：“这项研究表明，我们正走在同一条灭绝的道路上，问题是我们还能走多远。”



“So if you think about the Siberian Traps and the end-Permian massextinction as a feasibility study for global warming and sulfur geoengineering,the results of that study were … not the best,” he said, referring to, quiteliterally, the worst thing that’s ever happened. “It’s worth asking ourselveswhether we really want to make our current predicament even more like theend-Permian mass extinction.”

“所以，如果你把西伯利亚暗色岩喷发和二叠纪末期的大灭绝看作是全球变暖和硫地球工程的可行性研究，那么这项研究的结果并不是最好的，”他说，“我们有必要扪心自问，我们是否真的想让我们目前的困境看起来更像是二叠纪末期的大灭绝事件。”