二氧化碳的过度排放正在导致海洋酸化 - 海洋酸化化学反应

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作者：Triona McGrath

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    蓝色的海洋是地球最宝贵的资源，如果没有海洋，地球将成为荒芜的星球。海洋是生命的摇篮，不仅占据地球表面积的71％，而且还蕴藏着丰富的矿产资源、生物资源、动力资源、交通资源、医药资源和海水资源等。海洋对人类居住的地球环境和气候有着巨大调节作用，已成为地球生命支持系统的重要组成部分。然而自上个世纪五十年代以来，随着各国社会生产力和科学技术的迅猛发展，海洋受到了来自各方面不同程度的污染和破坏，日益严重的污染给人类的生存和发展带来了极为不利的后果。

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5 K% g1 [8 {" D8 J0 i: ^. c Do you ever think about how important the oceans are in our daily lives? The oceans cover two-thirds of our planet. They provide half the oxygen we breathe. They moderate our climate. And they provide jobs and medicine and food including 20 percent of protein to feed the entire world population. eople used to think that the oceans were so vast that they wouldnt be affected by human activities. 你们是否想过，海洋在我们的日常生活中有多么重要？ 海洋覆盖了地球三分之二的表面。 我们呼吸的氧气中， 一半是由海洋提供的。 它们能调节气候。 它们还能为我们 提供岗位、药材和食物， 包括全世界人口生存 所需蛋白质的20%。 人们曾经认为海洋广阔到 根本不会被人类活动所影响。Well today Im going to tell you about a serious reality that is changing our oceans called ocean acidification, or the evil twin of climate change. Did you know that the oceans have absorbed 25 percent of all of the carbon dioxide that we have emitted to the atmosphere? Now this is just another great service provided by the oceans since carbon dioxide is one of the greenhouse gases thats causing climate change. But as we keep pumping more and more and more carbon dioxide into the atmosphere more is dissolving into the oceans. And this is whats changing our ocean chemistry. When carbon dioxide dissolves in seawater, it undergoes a number of chemical reactions. 那么今天我要告诉你们 一个正在导致海洋变化的严酷现实——海洋酸化， 即伴随气候变化的另一个糟糕问题。 你们知道吗，我们排放进 大气里的二氧化碳 有25%被海洋吸收了。 这是海洋做出的又一大贡献， 因为二氧化碳是温室气体中的一种， 会造成气候变化。 但随着我们向大气中排放的 二氧化碳越来越多， 溶解进海洋的部分也越来越多。 这就改变了海洋的化学成分。 二氧化碳溶入海水后， 海水将发生许多化学反应。Now lucky for you, I dont have time to get into the details of the chemistry for today. But Ill tell you as more carbon dioxide enters the ocean, the seawater pH goes down. And this basically means that there is an increase in ocean acidity. And this whole process is called ocean acidification. And its happening alongside climate change. Scientists have been monitoring ocean acidification for over two decades. This figure is an important time series in Hawaii, and the top line shows steadily increasing concentrations of carbon dioxide, or CO2 gas, in the atmosphere. And this is directly as a result of human activities.还好， 因为时间不够，你们不必 听我解释化学反应的细节。 但我可以告诉你们， 随着更多的二氧化碳进入海洋 海水的pH值会下降。 这就意味着海洋酸度的上升。 这整个过程被称为海水酸化。 它伴随着气候变化一起发生。 科学家们已经监测了 海洋酸度超过20年。 这幅图显示了在夏威夷 收集的重要连续监测数据， 而最上面的折线反映了 大气中二氧化碳浓度的 稳步增长。 这是人类活动的直接结果。The line underneath shows the increasing concentrations of carbon dioxide that is dissolved in the surface of the ocean which you can see is increasing at the same rate as carbon dioxide in the atmosphere since measurements began. The line on the bottom shows then shows the change in chemistry. As more carbon dioxide has entered the ocean, the seawater pH has gone down, which basically means there has been an increase in ocean acidity. Now in Ireland, scientists are also monitoring ocean acidification -- scientists at the Marine Institute and NUI Galway. And we, too, are seeing acidification at the same rate as these main ocean time-series sites around the world. So its happening right at our doorstep. 下面的折线则反映了 溶解在海洋表面的 二氧化碳浓度不断升高， 你们可以看到，从有 测量记录开始，它的增长速率 就和大气中二氧化碳的 增长速率一致。 而最底部的折线反映了 海水化学成分的变化。 随着更多的二氧化碳进入海洋， 海水pH值下降了， 这也意味着海水酸度的升高。 在爱尔兰，来自海洋研究所 和爱尔兰国家学院戈尔韦分校的 科学家们也在监测海洋的酸化。 而我们也见证着海洋酸化 以和世界各地 其他海洋监测站点 同样的速度进行着。 所以海洋酸化就在我们眼前发生着。Now Id like to give you an example of just how we collect our data to monitor a changing ocean. Firstly we collect a lot of our samples in the middle of winter. So as you can imagine, in the North Atlantic we get hit with some seriously stormy conditions -- so not for any of you who get a little motion sickness, but we are collecting some very valuable data. So we lower this instrument over the side of the ship, and there are sensors that are mounted on the bottom that can tell us information about the surrounding water, such as temperature or dissolved oxygen. And then we can collect our seawater samples in these large bottles. So we start at the bottom, which can be over four kilometers deep just off our continental shelf, and we take samples at regular intervals right up to the surface. We take the seawater back on the deck, and then we can either analyze them on the ship or back in the laboratory for the different chemicals parameters. 现在我想给你们举个例子 来说明我们是如何收集数据 来监测不断变化的海洋的。 首先，我们的许多样本 都是在寒冬中采集的。 所以你们可以想象，在北大西洋 我们常常遇到波涛汹涌的海面—— 这带来的不仅仅是 一点晕船的症状， 我们也在收集非常珍贵的数据。 我们把设备从船的一侧放下去， 设备的底部装有许多传感器， 能够探测出周围海水的信息， 比如温度、溶氧量等。 然后我们把海水样本 装进这些大瓶子里。 我们从海底开始，大约在四千米深处 大陆架的上方， 一直到海水表面，都以 相同的间隔提取海水样本。 我们把海水样本拉到甲板上， 然后我们在船上或是实验室里， 分析海水中不同的化学成分参数。But why should we care? How is ocean acidification going to affect all of us? Well, here are the worrying facts. There has already been an increase in ocean acidity of 26 percent since pre-industrial times, which is directly due to human activities. Unless we can start slowing down our carbon dioxide emissions, were expecting an increase in ocean acidity of 170 percent by the end of this century. I mean this is within our childrens lifetime. This rate of acidification is 10 times faster than any acidification in our oceans for over 55 million years. So our marine life have never, ever experienced such a fast rate of change before. So we literally could not know how theyre going to cope. 我们为什么要在乎这些呢？ 海水酸化会怎样影响 我们所有人呢？ 这里有一些令人担忧的事实。 从工业化以前到现在， 海洋酸度已经增加了26%， 这是由人类活动直接导致的。 除非我们能逐渐 降低二氧化碳排放量， 否则在本世纪末， 海水酸度将增长170%。 这将发生在我们下一代中发生。 这个酸化的速度比过去5500万年 以来的酸化速度还要快上10倍。 我们的海洋从来没有经历过 如此高速的变化。 所以我们真的不知道 海洋将如何应对。Now there was a natural acidification event millions of years ago, which was much slower than what were seeing today. And this coincided with a mass extinction of many marine species. So is that what were headed for? Well, maybe. Studies are showing some species are actually doing quite well but many are showing a negative response. One of the big concerns is as ocean acidity increases, the concentration of carbonate ions in seawater decrease. Now these ions are basically the building blocks for many marine species to make their shells, for example crabs or mussels, oysters. 几百万年前曾经有过 自然发生的海洋酸化过程， 它比我们现在看到的酸化慢得多。 它和一场大规模的 海洋物种灭绝同时发生。 那么这也将是我们会面临的局面吗？ 嗯，也许吧。 研究表明有些物种生活得还不错， 可是许多物种已经表现出了消极反馈。 最令人担心的事情之一是 随着海水酸度增加， 海水中的碳酸根离子浓度会下降。 而这些离子正是许多海洋生物 外壳生长的原材料， 比如说螃蟹、贻贝、牡蛎等。Another example are corals. They also need these carbonate ions in seawater to make their coral structure in order to build coral reefs. As ocean acidity increases and the concentration of carbonate ions decrease, these species first find it more difficult to make their shells. And at even even lower levels, they can actually begin to dissolve. 另一个例子是珊瑚。 珊瑚虫也需要海水中的碳酸根离子 来筑造珊瑚礁。 而随着海洋酸度增加 和碳酸根离子的下降， 一开始，这些物种会 很难筑造他们的家， 离子水平更低时， 它们甚至会开始溶解。This here is a pteropod, its called a sea butterfly. And its an important food source in the ocean for many species, from krill to salmon right up to whales. The shell of the pteropod was placed into seawater at a pH that were expecting by the end of this century. After only 45 days at this very realistic pH, you can see the shell has almost completely dissolved. So ocean acidification could affect right up through the food chain -- and right onto our dinner plates. I mean who here likes shellfish? Or salmon? Or many other fish species whose food source in the ocean could be affected? 这是一个翼足目软体动物，被称做海蝶。 它是海洋中许多生物的重要食物来源， 包括磷虾、鲑鱼一直到鲸鱼。 我们把海蝶的壳放进海水中， 海水的pH值设定在我们预测的 本世纪末海水的pH值。 仅仅在45天后，在如此低的pH环境里， 你们可以看到它的壳 几乎被完全溶解了。 所以海洋酸化能通过影响食物链， 直接影响到我们的食物来源。 你们这里有谁喜欢吃 贝类或是鲑鱼的吗？ 或是别的食物来源 会被影响到的鱼类？These are cold-water corals. And did you know we actually have cold-water corals in Irish waters, just off our continental shelf? And they support rich biodiversity, including some very important fisheries. Its projected that by the end of this century, 70 percent of all known cold-water corals in the entire ocean will be surrounded by seawater that is dissolving their coral structure. The last example I have are these healthy tropical corals. They were placed in seawater at a pH were expecting by the year 2100. After six months, the coral has almost completely dissolved. Now coral reefs support 25 percent of all marine life in the entire ocean. All marine life. 这些是冷水珊瑚礁。 实际上，在爱尔兰海域 也有冷水珊瑚礁， 就在大陆架上。 它们维护着包括许多 重要渔场的生物多样性 。 预计在本世纪末， 整个海洋中70%已知的冷水珊瑚礁 将生活在会溶解珊瑚结构的海水中。 我要举的最后一个例子是 这些健康的热带珊瑚礁。 它们被放在我们预测 2100年会达到的pH值的海水中。 六个月后这些珊瑚 几乎被完全溶解了。 如今珊瑚礁维持着 整个海洋中25%的海洋生物的生命。 所有的海洋生物。So you can see: ocean acidification is a global threat. I have an eight-month-old baby boy. Unless we start now to slow this down, I dread to think what our oceans will look like when hes a grown man. We will see acidification. We have already put too much carbon dioxide into the atmosphere. But we can slow this down. We can prevent the worst-case scenario. The only way of doing that is by reducing our carbon dioxide emissions. This is important for both you and I, for industry, for governments. 所以你们可以看出：海洋酸化 是一个全球性的威胁。 我有一个八个月大的儿子。 除非我们从现在开始减慢酸化速度， 否则我都不敢想象我的儿子 长大后，海洋将变成什么样。 我们将看到海洋酸化。 我们已经向大气中排放了 太多的二氧化碳。 但是我们可以放慢酸化速度。 我们可以阻止最坏的状况发生。 唯一的方法是 减少碳排放量。 这对你我、工业界和 政府来说，都至关重要。We need to work together, slow down global warming slow down ocean acidification and help to maintain a healthy ocean and a healthy planet for our generation and for generations to come. 我们需要携手努力，放慢全球变暖， 放慢海洋酸化， 维护健康的海洋，和健康的地球， 为了我们这一代， 也为了我们的后代。

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