存活之本|《经济学人》：海洋哺育了人类，人类却糟蹋了海洋
欢迎打开“我与我们的世界”，从此，让我们一起“纵览世界之风云变幻、洞察社会之脉搏律动、感受个体之生活命运、挖掘自然之点滴奥妙”。
我与我们的世界，既是一个“奋斗”的世界，也是一个“思考”的世界。奋而不思则罔，思而不奋则殆。这个世界，你大，它就大；你小，它就小。
欢迎通过上方公众号名称打开公众号“查看历史信息”来挖掘往期文章，因为，每期都能让你“走近”不一样的世界、带给你不一样的精彩。
本期导读：海洋是地球上最广阔的水体的总称。地球上海洋面积约为3.6亿平方公里，约占地球表面积的71%，远远大于陆地面积，故地球堪称为一个“大水球”。
海洋含有十三亿五千多万立方千米的水，约占地球上总水量的97%。地球上四个主要的大洋为太平洋、大西洋、印度洋、北冰洋，大部分以陆地和海底地形线为界。目前为止，人类已探索的海底只有5%，还有95%大海的海底是未知的。
海水温度是反映海水冷热状况的一个物理量。世界海洋的水温变化一般在-2℃-30℃之间，其中年平均水温超过20℃的区域占整个海洋面积的一半以上。海水温度有日、月、年、多年等周期性变化和不规则的变化，它主要取决于海洋热收支状况及其时间变化。
世界各大海洋的海水所含的盐分各处不同，平均约为3.5%，这些溶解在海水中的无机盐，最常见的是氯化钠，即日用的食盐。有些盐来自海底的火山，但大部分是来自地壳的岩石。岩石受风化而崩解，释出盐类，再由河水带到海里去。
海洋是地球上决定气候发展的主要的因素之一。海洋本身就是地球表面最大的储热体。海流是地球表面最大的热能传送带。海洋与空气之间的气体交换，其中最主要的有水汽、二氧化碳和甲烷，对气候的演变有着特别大的影响。
海水水体以及海洋中的各种组成物质，构成对人类生存和发展有着重要意义的海洋环境。海水运动是海洋环境的核心内容，主要由四部分构成：海水运动形式；洋流的成因；表层洋流的分布；洋流对地理环境的影响。
全球的大洋环流，对高、低纬度间的热量输送和交换、调节全球的热量分布有重要意义。洋流对流经海区的沿岸气候、海洋生物分布和渔业生产，航海等都有影响，对人类文明进程和社会生活有着重要的影响。
Deep trouble
海洋深处问题深
How to improve the health of the ocean
如何改善海洋生态健康
The ocean sustains humanity. Humanity treats it with contempt
海洋哺育了人类，人类却糟蹋了海洋。
Humans are wrecking the ocean. Technology shows the scale of the problem-and offers some solutions.
人类正在毁灭海洋。利用科学技术，能探测出问题的严重性，同时，通过科学技术，也能找到某些解决方案。
EARTH is poorly named. The ocean covers almost three-quarters of the planet. It is divided into five basins: the Pacific, the Atlantic, the Indian, the Arctic and the Southern oceans. Were all the planet’s water placed over the United States, it would form a column of liquid 132km tall. The ocean provides 3bn people with almost a fifth of their protein (making fish a bigger source of the stuff than beef). Fishing and aquaculture assure the livelihoods of one in ten of the world’s people. Climate and weather systems depend on the temperature patterns of the ocean and its interactions with the atmosphere. If anything ought to be too big to fail, it is the ocean.
“地球”这个名字起的不怎么地。在被称为地球的这颗行星上，几乎四分之三的面积都是由海水而不是土地所覆盖。若把地球上所有的水全部搞没，就会裸露出五个盆地：太平盆地、大西盆地、印度盆地、北极盆地以及南洋盆地。若把地球上所有的水在美国国土上堆积起来，将会形成高达132千米之高的水体巨柱。海洋，为30亿人提供了所需的近五分之一的蛋白营养，这也使得鱼类成为一种比牛肉还更为重要的食物来源。世界人口中有十分之一的人靠渔业和水产养殖为生。气候及天气系统也依赖于海洋的温度场及其与大气层之间的动态互动。若这个世间还有什么“如此庞大、如此重要而不能出问题”的东西的话，那么，它就是海洋。
Humans have long assumed that the ocean’s size allowed them to put anything they wanted into it and to take anything they wanted out. Changing temperatures and chemistry, overfishing and pollution have stressed its ecosystems for decades. The ocean stores more than nine-tenths of the heat trapped on Earth by greenhouse-gas emissions. Coral reefs are suffering as a result; scientists expect almost all corals to be gone by 2050.
很长时间以来，人类一直认为，海洋是如此之大，人们想往里面扔什么就能扔什么，想从里面捞什么就能捞什么。过去的几十年间，海洋水体温度一直在变，海水化学成分也在渐变，海洋渔业资源过度开采，海洋水体污染日渐严重，这一切，都对海洋生态系统形成严峻挑战。地球上温室气体所吸收的热量，有超过九成存贮于海洋。结果，海水温度上升，珊瑚礁遭了殃。科学家们预测，到2050年，几乎所有的珊瑚礁都将消亡。
注：珊瑚礁是石珊瑚目的动物形成的一种结构，这个结构可以大到影响其周围环境的物理和生态条件。在深海和浅海中均有珊瑚礁存在，它们是成千上万的由碳酸钙组成的珊瑚虫的骨骼在数百年至数千年的生长过程中形成的。珊瑚礁为许多动植物提供了生活环境，其中包括蠕虫、软体动物、海绵、棘皮动物和甲壳动物，此外珊瑚礁还是海洋鱼类的幼鱼生长地。
By the middle of the century the ocean could contain more plastic than fish by weight. Ground down into tiny pieces, it is eaten by fish and then by people, with uncertain effects on human health. Appetite for fish grows nevertheless: almost 90% of stocks are fished either at or beyond their sustainable limits. The ocean nurtures humanity. Humanity treats it with contempt.
到本世纪中叶，漂浮于海洋中的废弃塑料的重量，将可能会超过漂游于海洋中的鱼类的重量。废弃塑料慢慢会解体变小，然后就会被鱼类吃掉，然后再被人类吃掉，这样，也就会对人类健康造成不确定性影响。人类对鱼类的胃口，一直在膨胀，几乎九成的渔业资源，开采程度不是已经到了就是已经超过可持续发展的极限。海洋哺育了人类，人类却糟蹋了海洋。
Depths plumbed
问题需要捋一捋
Such self-destructive behaviour demands explanation. Three reasons for it stand out. One is geography. The bulk of the ocean is beyond the horizon and below the waterline. The damage being done to its health is visible in a few liminal places—the Great Barrier Reef, say, or the oyster farms of Washington state. But for the most part, the sea is out of sight and out of mind. It is telling that there is only a single fleeting reference to the ocean in the Paris agreement on climate change.
人类之所以产生如此严重的自我毁灭行为，原因大概有三，首先，是海洋的体量如此之庞大；其次，是海洋的治理有问题；最后，是人类的其他行为也危及了海洋。问题的解决路径也大体有三，首先，可利用科学技术把问题及其严重性搞清楚；其次，可通过提高信息透明度来改进海洋治理；最后，可通过信息普及来影响人们的日常生活行为。
A second problem is governance. The ocean is subject to a patchwork of laws and agreements. Enforcement is hard and incentives are often misaligned. Waters outside national jurisdictions—the high seas—are a global commons. Without defined property rights or a community invested in their upkeep, the interests of individual actors in exploiting such areas win out over the collective interest in husbanding them. Fish are particularly tricky because they move. Why observe quotas if you think your neighbour can haul in catches with impunity?
Third, the ocean is a victim of other, bigger processes. The emission of greenhouse gases into the atmosphere is changing the marine environment along with the rest of the planet. The ocean has warmed by 0.7°C since the 19th century, damaging corals and encouraging organisms to migrate towards the poles in search of cooler waters. Greater concentrations of carbon dioxide in the water are making it more acidic. That tends to harm creatures such as crabs and oysters, whose calcium carbonate shells suffer as marine chemistry alters.
Some of these problems are easier to deal with than others. “Ocean blindness” can be cured by access to information. And indeed, improvements in computing power, satellite imaging and drones are bringing the ocean into better view than ever before. Work is under way to map the sea floor in detail using sonar technology. On the surface, aquatic drones can get to remote, stormy places at a far smaller cost than manned vessels. From above, ocean-colour radiometry is improving understanding of how phytoplankton, simple organisms that support marine food chains, move and thrive. Tiny satellites, weighing 1-10kg, are enhancing scrutiny of fishing vessels.
Transparency can also mitigate the second difficulty, of ocean governance. More scientific data ought to improve the oversight of nascent industries. As sea-floor soundings proliferate, the supervision of deep-sea mining, which is overseen by the International Seabed Authority in areas beyond national jurisdiction, should get better. More data and analysis also make it easier to police existing agreements. Satellite monitoring can provide clues to illegal fishing activity: craft that switch off their tracking devices when they approach a marine protected area excite suspicion, for example. Such data make it easier to enforce codes like the Port State Measures Agreement, which requires foreign vessels to submit to inspections at any port of call and requires port states to share information on any suspected wrongdoing they find.
Clearer information may also help align incentives and allow private capital to reward good behaviour. Insurance firms, for instance, have an incentive to ask for more data on fishing vessels; if ships switch off their tracking systems, the chances of collisions rise, and so do premiums. Greater traceability gives consumers who are concerned about fish a way to press seafood firms into behaving responsibly.
Sunk costs
沉没成本
注：沉没成本是指由于过去的决策已经发生了的，而不能由现在或将来的任何决策改变的成本。人们在决定是否去做一件事情的时候，不仅是看这件事对自己有没有好处，而且也看过去是不是已经在这件事情上有过投入。我们把这些已经发生不可收回的支出，如时间、金钱、精力等称为“沉没成本”（Sunk Cost）。在经济学和商业决策制定过程中会用到“沉没成本”的概念，代指已经付出且不可收回的成本。沉没成本常用来和可变成本作比较，可变成本可以被改变，而沉没成本则不能被改变。
Thanks to technology, the ocean’s expanse and remoteness are becoming less formidable—and less of an excuse for inaction. A UN meeting on the ocean next month in New York is a sign that policymakers are paying more attention to the state of the marine realm. But superior information does not solve the fundamental problem of allocating and enforcing property rights and responsibilities for the high seas. And the effectiveness of incentives to take care of the ocean varies. Commercial pay-offs from giving fish stocks time to recover, for example, are large and well-documented; but the rewards that accrue from removing plastic from the high seas are unclear.
多亏有科学技术的进步，人类在茫茫海洋面前已有能力不再望而却步，也因此，人类也不能再找出什么站得住脚的理由来为自己的不作为而辩护。科学技术的进步，使得了解海洋所面临的挑战不再成为问题，但解决问题的方案的落实，却不会因科学技术的进步而变得不再是个麻烦。人类对自己给海洋带来伤害这回事儿心如明镜，不过，是否能停止这种伤害却完全是另一回事儿。
Above all, better measurement of global warming’s effect on the ocean does not make a solution any easier. The Paris agreement is the single best hope for protecting the ocean and its resources. But America is not strongly committed to the deal; it may even pull out. And the limits agreed on in Paris will not prevent sea levels from rising and corals from bleaching. Indeed, unless they are drastically strengthened, both problems risk getting much worse. Mankind is increasingly able to see the damage it is doing to the ocean. Whether it can stop it is another question.
往期精彩：
趣图+趣文|《善于发现的眼睛》：点滴之间有深意，细微之处见精神
生命之谜|施一公：生命之源或缘于35亿年前的一团量子纠缠，人类认知或囿于自身生命的物质形式局限
中国式神话|《儒家神话》：神话，在传说中，在古籍里，也在你我身边
气候变化|《经济学人》：有没有美国，都一个样儿，地球都会照样转
注：
1：后台回复“20170527”，可获本期《经济学人》下载方式。
2：本文为原创，若发现不错，欢迎转发共享。
3：英文转自《经济学人》，非商业用途。
4：可将本公众号设为“置顶公众号”，第一时间收到最新消息。
5：若有任何方面的问题，可随时联系进行沟通。
6：关注可搜索“我与我们的世界”或扫描下方二维码：