Hotter water, slimier slime更热的水，更粘的泥
Warming also has consequences for ice: it melts. Melting sea ice affects ecosystems and currents. It does not affect sea levels, because floating ice is already displacing water of a weight equal to its own. But melting glaciers and ice sheets on land are bringing quantities of fresh water into the sea, whose level has been rising at an average of nearly 2 millimetres a year for over 40 years, and the pace is getting faster. Recent studies suggest that the sea level may well rise by a total of 80 centimetres this century, though the figure could plausibly be as much as 2 metres.
气候变暖对冰同样有影响：冰因此融化。海冰融化会影响生态系统和水流。由于浮冰重力和它排开的水的重力相等，所以它对海平面没有影响。但是，陆地上的冰河和大冰原要是融化了，就会往海里注入大量淡水，一旦如此，海平面上升的速度还会加快，而40多年来，海平面已经以年均近2毫米的速度上升了。近来的研究表明，本世纪海平面总体上升值完全有可能达到80厘米，但就算该数据是2米也不是不可能。
The burning over the past 100 years or so of fossil fuels that took half a billion years to form has suddenly, in geological terms, put an enormous amount of carbon dioxide into the atmosphere. About a third of this CO2 is taken up by the sea, where it forms carbonic acid. The plants and animals that have evolved over time to thrive in slightly alkaline surface waters—their pH is around 8.3—are now having to adapt to a 30% increase in the acidity of their surroundings. Some will no doubt flourish, but if the trend continues, as it will for at least some decades, clams, mussels, conches and all creatures that grow shells made of calcium carbonate will struggle. So will corals, especially those whose skeletons are composed of aragonite, a particularly unstable form of calcium carbonate.
从地质学角度来说，在过去100年左右，化石燃料的使用往大气中排入大量二氧化碳，而这些化石燃料需要5亿年才能形成。1/3的二氧化碳被海洋所吸收，形成碳酸。在漫长的进化过程中，海洋动植物已经习惯了海面的弱碱性——PH值大约为8.3，但现在它们不得不去适应所处环境酸度30%的下降。有些物种会因此得到短暂繁荣，这是毫无疑问的，这种趋势至少在接下来的几十年内还会继续，但假如那时还不停止，那么，包括蛤、蚌、海螺等具有由碳酸钙形成的贝壳的贝类动物的生存就堪忧了。珊瑚礁对此也受到同样的危险，对于骨骼由霰石（极不稳定的碳酸钙）构成的珊瑚来说，情况更是如此。
Man’s interference does not stop with CO2. Knowingly and deliberately, he throws plenty of rubbish into the sea, everything from sewage to rubber tyres and from plastic packaging to toxic waste. Inadvertently, he also lets flame retardants, bunker oil and heavy metals seep into the mighty ocean, and often invasive species too. Much of the harm done by such pollutants is invisible to the eye: it shows up only in the analysis of dead polar bears or in tuna served in New York sushi bars.
二氧化碳的排放并未没有因为人类的干涉停止。尽管心知肚明，但污水、轮胎、塑料袋、有毒废物统统都往海里倒；而不经意间，又让阻化剂、燃料油、重金属流入强大的海洋，也往往进入肉食生物体内。这些污染物的害处又往往是无形的：惟有当人们对北极熊尸检，或是在纽约寿司店检验金枪鱼时，这个问题才会浮现出来。
Increasingly, though, swimmers, sailors and even those who monitor the sea with the help of satellites are encountering highly visible algal blooms known as red tides. These have always occurred naturally, but they have increased in frequency, number and size in recent years, notably since man-made nitrogen fertilisers came into widespread use in the 1950s. When rainwater contaminated with these fertilisers and other nutrients reaches the sea, as it does where the Mississippi runs into the Gulf of Mexico, an explosion of toxic algae and bacteria takes place, killing fish, absorbing almost all the oxygen and leaving a microbially dominated ecosystem, often based on a carpet of slime.
然而，由于海藻爆发生殖产生的赤潮现象，发生次数却越来越多，这是游泳者、水手、甚至是通过卫星检测海域的人有目共睹的。赤潮现象过去是自然现象，但近年来，它的频率、次数、规模都有所上升，尤其是自从上世纪50年代，人造氮肥的广泛使用以来更甚。随着受这些化肥及其他营养物污染的雨水排入大海，有毒藻类、细菌爆发性生殖，几乎将溶解氧消耗怠尽，导致鱼类死亡，生态系统为微生物所支配，这又往往是基于一层黏液的，密西西比河注入墨西哥湾也会发生这种情况。
Each of these phenomena would be bad enough on its own, but all appear to be linked, usually synergistically. Slaughter one species in the food web and you set off a chain of alterations above or below. Thus the near extinction of sea otters in the northern Pacific led to a proliferation of sea urchins, which then laid waste an entire kelp forest that had hitherto sustained its own ecosystem. If acidification kills tiny sea snails known as pteropods, as it is likely to, the Pacific salmon that feed upon these planktonic creatures may also die. Then other fish may move in, preventing the salmon from coming back, just as other species did when cod were all but fished out in Georges Bank, off New England.
就算是只针对个体，这些情况就已经很棘手了，但所有这些却存在联系，而且往往是相互促进。在整个食物链中，一旦有一个物种遭到破坏，那么上下层结构都因此发生连锁改变。所以说，北太平北部几近灭绝的海懒导致了海胆的疯长，海胆的排泄物又导致了一整片海藻森林形成，至今仍保持其自己的生态系统。又比如，海水酸化导致翼足目纲的海螺死亡，那么，以这些浮游生物为食的大鳞大麻哈鱼也会一并死亡。接着，其他鱼类就会占领该地，防止其他大麻哈鱼回来，当时新英格兰的乔治海岸的鳕几乎灭绝时也是这样的。
Whereas misfortunes that came singly might not prove fatal, those that come in combination often prove overwhelming. The few coral reefs that remain pristine seem able to cope with the warming and acidification that none can escape, but most of the reefs that have also suffered overfishing or pollution have succumbed to bleaching or even death. Biodiversity comes with interdependence, and the shocks administered by mankind in recent decades have been so numerous and so severe that the natural balance of marine life is everywhere disturbed.
这种“倒霉事”要是单枪匹马那还算不上弥天大祸，一旦同恶相求，那就真会是灭顶之灾了。现在还没受到污染的少数珊瑚礁似乎能够应付气候变暖和海水酸化，这是谁也不能避免的，但大多数珊瑚由于过度捕捞或是污染已经产生“漂白现象”甚至死亡了。生态多样性源于相互依赖，然而近几十年来人类对其冲击太巨大，以致海洋生物的自然平衡遭到破坏的情况比比皆是。
Are these changes reversible? Most scientists believe that fisheries, for instance, could be restored to health with the right policies, properly enforced. But many of the changes are speeding up, not slowing down. Some, such as the acidification of the seas, will continue for years to come simply because of events already in train or past. And some, such as the melting of the Arctic ice cap, may be close to the point at which an abrupt, and perhaps irreversible, series of happenings is set in motion.
这些变化还有扭转的余地吗？以渔业为例，多数科学家认为，只要政策有利、实施得当，这个行业还是能够健康发展的。但是，许多变化速度有增无减。像海水酸化这类的变化，只因为事情马上就会发生或者已经发生了，这种变化就会持续数年。还有一些，比如北极冰帽融化，可能要到情况变得一发不可收拾前才能悬崖勒马，甚至可能刹都刹不住车。
It is clear, in any event, that man must change his ways. Humans could afford to treat the sea as an infinite resource when they were relatively few in number, capable of only rather inefficient exploitation of the vasty deep and without as yet a taste for fossil fuels. A world of 6.7 billion souls, set to become 9 billion by 2050, can no longer do so. The possibility of widespread catastrophe is simply too great.
无论如何，人类必须做出改变，这是显而易见的。惟有当人类数量屈指可数、对海洋开发需求寥寥无几，完全不用化石燃料时，人类才可以拍着胸脯认为海洋资源用之不竭。但对于一个人口达到67亿，2050即将达到90亿的世界，我们没有那本钱了。发生大规模灾难的可能性实在太大了。
