WEBVTT 00:00:01.627 --> 00:00:05.960 Do you ever think about how important the oceans are in our daily lives? 00:00:07.830 --> 00:00:10.576 The oceans cover two thirds of our planet. 00:00:11.190 --> 00:00:13.591 They provide half the oxygen we breathe. 00:00:14.036 --> 00:00:15.690 They moderate our climate. 00:00:16.055 --> 00:00:19.832 And they provide jobs and medicine and food 00:00:20.181 --> 00:00:25.125 including 20 percent of protein to feed the entire world population. 00:00:26.331 --> 00:00:28.847 People used to think that the oceans were so vast 00:00:28.872 --> 00:00:31.332 that they wouldn't be affected by human activities. NOTE Paragraph 00:00:32.205 --> 00:00:35.491 Well today I'm going to tell you about a serious reality 00:00:35.516 --> 00:00:40.148 that is changing our oceans called ocean acidification, 00:00:40.363 --> 00:00:42.728 or the evil twin of climate change. 00:00:43.900 --> 00:00:49.322 Did you know that the oceans have absorbed 25 percent of all of the carbon dioxide 00:00:49.347 --> 00:00:51.590 that we have emitted to the atmosphere? 00:00:51.970 --> 00:00:55.608 Now this is just another great service provided by the oceans 00:00:55.633 --> 00:00:58.502 since carbon dioxide is one of the greenhouse gases 00:00:58.527 --> 00:01:00.283 that's causing climate change. 00:01:01.310 --> 00:01:05.346 But as we keep pumping more and more and more 00:01:05.372 --> 00:01:07.864 carbon dioxide into the atmosphere 00:01:08.030 --> 00:01:10.483 more is dissolving into the oceans. 00:01:10.803 --> 00:01:13.723 And this is what's changing our ocean chemistry. 00:01:15.350 --> 00:01:17.738 When carbon dioxide dissolves in seawater, 00:01:17.763 --> 00:01:20.001 it undergoes a number of chemical reactions. NOTE Paragraph 00:01:20.420 --> 00:01:21.585 Now lucky for you, 00:01:21.610 --> 00:01:24.895 I don't have time to get into the details of the chemistry for today, 00:01:25.388 --> 00:01:28.712 but I'll tell you as more carbon dioxide enters the ocean, 00:01:28.737 --> 00:01:31.094 the seawater pH goes down. 00:01:31.730 --> 00:01:35.697 And this basically means that there is an increase in ocean acidity. 00:01:36.348 --> 00:01:40.470 And this whole process is called ocean acidification. 00:01:40.904 --> 00:01:43.630 And it's happening alongside climate change. 00:01:44.356 --> 00:01:48.459 Scientists have been monitoring ocean acidification for over two decades. 00:01:48.998 --> 00:01:51.671 This figure is an important time series in Hawaii, 00:01:51.696 --> 00:01:56.591 and the top line shows steadily increasing concentrations of carbon dioxide, 00:01:56.616 --> 00:01:59.131 or CO2 gas, in the atmosphere. 00:01:59.242 --> 00:02:02.488 And this is directly as a result of human activities. 00:02:03.340 --> 00:02:07.371 The line underneath shows the increasing concentrations of carbon dioxide 00:02:07.396 --> 00:02:10.332 that is dissolved in the surface of the ocean 00:02:10.578 --> 00:02:13.537 which you can see is increasing at the same rate 00:02:13.562 --> 00:02:16.736 as carbon dioxide in the atmosphere since measurements began. 00:02:16.927 --> 00:02:19.934 The line on the bottom shows then shows the change in chemistry. 00:02:19.959 --> 00:02:22.785 As more carbon dioxide has entered the ocean, 00:02:22.810 --> 00:02:25.056 the seawater pH has gone down, 00:02:25.551 --> 00:02:29.598 which basically means there has been an increasein ocean acidity. 00:02:31.185 --> 00:02:35.255 Now in Ireland, scientists are also monitoring ocean acidification -- 00:02:35.280 --> 00:02:38.073 scientists at the Marine Institute and NUI Galway. 00:02:38.224 --> 00:02:42.373 And we, too, are seeing acidification at the same rate 00:02:42.398 --> 00:02:45.405 as these main ocean time-series sites around the world. 00:02:45.866 --> 00:02:48.739 So it's happening right at our doorstep. NOTE Paragraph 00:02:49.570 --> 00:02:52.728 Now I'd like to give you an example of just how we collect our data 00:02:52.753 --> 00:02:55.006 to monitor a changing ocean. 00:02:55.189 --> 00:02:58.244 Firstly we collect a lot of our samples in the middle of winter. 00:02:58.269 --> 00:03:00.408 So as you can imagine, in the North Atlantic 00:03:00.433 --> 00:03:03.038 we get hit with some seriously stormy conditions -- 00:03:03.149 --> 00:03:05.782 so not for any of you who get a little motion sickness, 00:03:05.807 --> 00:03:08.235 but we are collecting some very valuable data. 00:03:08.592 --> 00:03:11.471 So we lower this instrument over the side of the ship, 00:03:11.496 --> 00:03:13.932 and there are sensors that are mounted on the bottom 00:03:13.957 --> 00:03:16.630 that can tell us information about the surrounding water, 00:03:16.655 --> 00:03:19.075 such as temperature or dissolved oxygen. 00:03:19.450 --> 00:03:23.265 And then we can collect our seawater samples in these large bottles. 00:03:23.432 --> 00:03:26.684 So we start at the bottom, which can be over four kilometers deep 00:03:26.709 --> 00:03:28.566 just off our continental shelf, 00:03:28.812 --> 00:03:32.478 and we take samples at regular intervals right up to the surface. 00:03:32.875 --> 00:03:35.136 We take the seawater back on the deck, 00:03:35.271 --> 00:03:37.650 and then we can either analyze them on the ship 00:03:37.675 --> 00:03:40.810 or back in the laboratory for the different chemicals parameters. NOTE Paragraph 00:03:41.167 --> 00:03:42.453 But why should we care? 00:03:42.651 --> 00:03:47.095 How is ocean acidification going to affect all of us? 00:03:48.754 --> 00:03:51.666 Well, here are the worrying facts. 00:03:52.777 --> 00:03:58.579 There has already been an increase in ocean acidity of 26 percent 00:03:58.604 --> 00:04:02.611 since pre-industrial times, which is directly due to human activities. 00:04:03.651 --> 00:04:07.738 Unless we can start slowing down our carbon dioxide emissions, 00:04:08.031 --> 00:04:13.968 we're expecting an increase in ocean acidity of 170 percent 00:04:14.388 --> 00:04:16.737 by the end of this century. 00:04:17.713 --> 00:04:20.046 I mean this is within our children's lifetime. 00:04:21.505 --> 00:04:27.123 This rate of acidification is 10 times faster 00:04:27.148 --> 00:04:33.569 than any acidification in our oceans for over 55 million years. 00:04:34.060 --> 00:04:38.431 So our marine life have never, ever experienced 00:04:38.456 --> 00:04:41.225 such a fast rate of change before. 00:04:41.551 --> 00:04:45.450 So we literally could not know how they're going to cope. NOTE Paragraph 00:04:47.035 --> 00:04:51.621 Now there was a natural acidification event millions of years ago, 00:04:51.646 --> 00:04:54.519 which was much slower than what we're seeing today. 00:04:54.780 --> 00:04:59.621 And this coincided with a mass extinction of many marine species. 00:05:00.891 --> 00:05:02.478 So is that what we're headed for? 00:05:03.270 --> 00:05:04.420 Well, maybe. 00:05:05.031 --> 00:05:08.523 Studies are showing some species are actually doing quite well 00:05:08.548 --> 00:05:11.538 but many are showing a negative response. 00:05:13.086 --> 00:05:17.133 One of the big concerns is as ocean acidity increases, 00:05:17.427 --> 00:05:21.681 the concentration of carbonate ions in seawater decrease. 00:05:22.490 --> 00:05:25.401 Now these ions are basically the building blocks 00:05:25.426 --> 00:05:28.227 for many marine species to make their shells, 00:05:28.759 --> 00:05:33.314 for example crabs or mussels, oysters. 00:05:33.774 --> 00:05:35.734 Another example are corals. 00:05:35.932 --> 00:05:39.113 They also need these carbonate ions in seawater 00:05:39.138 --> 00:05:43.043 to make their coral structure in order to build coral reefs. 00:05:44.367 --> 00:05:46.557 As ocean acidity increases 00:05:46.779 --> 00:05:50.009 and the concentration of carbonate ions decrease, 00:05:50.462 --> 00:05:54.922 these species first find it more difficult to make their shells. 00:05:55.231 --> 00:05:59.040 And at even even lower levels, they can actually begin to dissolve . 00:06:00.215 --> 00:06:03.278 This here is a theropod, it's called a sea butterfly. 00:06:03.516 --> 00:06:06.690 And it's an important food source in the ocean for many species, 00:06:06.952 --> 00:06:10.475 from krill to salmon right up to whales. 00:06:11.388 --> 00:06:14.902 The shell of the theropod was placed into seawater 00:06:14.927 --> 00:06:18.347 at a pH that we're expecting by the end of this century. 00:06:19.204 --> 00:06:24.696 After only 45 days at this very realistic pH, 00:06:25.040 --> 00:06:29.182 you can see the shell has almost completely dissolved. 00:06:29.555 --> 00:06:33.689 So ocean acidification could affect right up through the food chain -- 00:06:33.824 --> 00:06:35.935 and right onto our dinner plates. 00:06:36.474 --> 00:06:40.116 I mean who here likes shellfish? Or salmon? 00:06:40.682 --> 00:06:42.310 Or many other fish species 00:06:42.335 --> 00:06:45.178 whose food source in the ocean could be affected? 00:06:46.126 --> 00:06:47.973 These are cold-water corals. 00:06:48.112 --> 00:06:51.645 And did you know we actually have cold-water corals in Irish waters, 00:06:51.670 --> 00:06:53.517 just off our continental shelf? 00:06:54.023 --> 00:06:58.142 And they support rich biodiversity, including some very important fisheries. 00:06:58.856 --> 00:07:01.943 It's projected that by the end of this century, 00:07:02.226 --> 00:07:08.190 70 percent of all known cold-water corals in the entire ocean 00:07:08.577 --> 00:07:13.271 will be surrounded by seawater that is dissolving their coral structure. 00:07:16.850 --> 00:07:20.508 The last example I have are these healthy tropical corals. 00:07:21.072 --> 00:07:25.820 They were placed in seawater at a pH we're expecting by the year 2100. 00:07:27.484 --> 00:07:32.998 After six months, the coral has almost completely dissolved. 00:07:34.170 --> 00:07:36.535 Now coral reefs support 00:07:36.606 --> 00:07:43.133 25 percent of all marine life in the entire ocean. 00:07:43.870 --> 00:07:45.020 All marine life. NOTE Paragraph 00:07:46.068 --> 00:07:50.393 So you can see: ocean acidification is a global threat. 00:07:51.038 --> 00:07:53.160 I have an 8 month old baby boy. 00:07:53.980 --> 00:07:57.837 Unless we start now to slow this down, 00:07:58.003 --> 00:08:02.368 I dread to think what our oceans will look like when he's a grown man. 00:08:03.700 --> 00:08:05.668 We will see acidification. 00:08:05.830 --> 00:08:10.070 We have already put too much carbon dioxide into the atmosphere. 00:08:11.030 --> 00:08:13.712 But we can slow this down. 00:08:14.096 --> 00:08:18.472 We can prevent the worst-case scenario. 00:08:18.750 --> 00:08:20.934 The only way of doing that 00:08:21.013 --> 00:08:24.317 is by reducing our carbon dioxide emissions. 00:08:25.010 --> 00:08:29.416 This is important for both you and I, for industry, for governments. NOTE Paragraph 00:08:29.600 --> 00:08:33.371 We need to work together, slow down global warming 00:08:33.500 --> 00:08:35.881 slow down ocean acidification 00:08:36.080 --> 00:08:40.813 and help to maintain a healthy ocean and a healthy planet 00:08:40.839 --> 00:08:44.130 for our generation and for generations to come. NOTE Paragraph 00:08:45.324 --> 00:08:49.827 (Applause)