The marine world
Humans are wrecking the ocean. Technology shows the scale of the problem—and offers some solutions
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”这个名字起得不好，这个星球表面四分之三都是海洋，分为五个海洋盆地：太平洋、大西洋、印度洋、北冰洋和南冰洋。如果将地球上所有的水都集中到美国国土之上，将形成一道132千米高的巨型水柱。海洋为30亿人口提供了近五分之一的蛋白质，使得鱼类成为比牛肉更大的蛋白质来源。渔业和水产养殖是世界十分之一人口的生计所依。气候和天气系统取决于海洋的温度模式及其与大气的相互作用。如果说有什么事情万般紧要，容不得一点差池，那就数海洋了。
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.人类长久以来都以为，既然海洋浩瀚无边，人类可以任意倾倒废物、予取予求。数十年来，海洋温度和化学环境的变化，以及过度捕捞和污染都让海洋生态系统不堪重荷。被温室气体困在地球上的热量有九成以上都储存在大海里，珊瑚礁因此遭殃。科学家预计，到2050年，珊瑚礁将消失殆尽。
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 (see pages 22-24). The ocean nurtures humanity. Humanity treats it with contempt.到本世纪中叶，海洋中塑料垃圾的总重量可能将超过鱼类。磨成细小碎片的塑料被鱼吃掉，人再吃鱼，这对人体健康的影响仍未可知。然而人类对鱼类的需求仍在增长：近90%的鱼类的捕捞量已达到或超出可持续的限度。海洋滋养人类，人类却回以傲慢不恭。
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.
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?第二个问题是治理。海洋保护方面的法律和协议不成体系，执行难度大，而激励措施又往往不一致。国家管辖范围以外的水域(即公海)为全球共有，没有明确的所属权，也没有哪个团体投资来维护它们，单个国家肆意开发这些海域的利益就会凌驾于有节制地利用海洋资源的共同利益之上。鱼会游来游去，因而是个特别棘手的问题。如果你觉得邻国能大肆捕鱼而无需承担任何后果，自己为什么还要死守捕鱼配额规定呢?
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.第三个原因是，海洋本身是其他更大变化的受害者。排放到大气层中的温室气体让海洋环境与地球其他部分都在发生改变。19世纪以来，海水温度已经上升了0.7°C，破坏了珊瑚礁，导致生物朝极地更冷的水域迁徙。海水中二氧化碳的浓度越来越高，以致酸性越来越强，常会伤害诸如螃蟹和牡蛎等生物，它们由碳酸钙构成的外壳会因海洋化学环境的变化而受损。
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.以上这些问题中，有些解决起来会容易一些。“海洋破坏无知症”可以通过获得信息来治愈。事实上，计算能力、卫星成像和无人机技术的改进正在让人们以前所未有的程度了解海洋。声纳技术正在详细测绘海底地貌;在海面上，水上无人机可以到达暴风雨肆虐的遥远海域，成本比载人船只低得多;在海面上空，海洋水色辐射测量技术正在帮助人们了解支撑起海洋食物链的简单生物体浮游植物是如何移动和大量生长的;重量在1到10公斤的微型卫星则正在加强对渔船的监督。
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.增加透明度也可以减轻海洋治理这第二个难题。不断累积的科学数据应该会改善对新兴行业的监督。随着海底探测的范围迅速扩大，国际海底管理局在各国领海以外海域对深海采矿的监督应该会有所改善。更多的数据和分析也让现有协议的执行情况更容易受到监督。卫星监控可以提供非法捕鱼活动的线索，例如，船只在接近海洋保护区时关闭船上跟踪装置就会引起怀疑。这样的数据使执行像《港口国措施协定》这类法规变得更为容易。该协定要求外国船只接受停靠港的检查，并要求港口国分享所发现的任何可疑不法行为的信息。
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.信息更加公开透明也可能有助于协调激励措施，让私人资本去奖励良好行为。例如，保险公司会更有动力要求渔船提供更多数据，如果船只关闭跟踪系统，撞船的机率就会上升，保费也会随之上升。提高可追溯性能让关心鱼类的消费者得以对海产品公司施压，让它们行事更负责任。
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 in June 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.
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.