1 00:00:04,360 --> 00:00:12,430 Well, hello, everybody, and welcome to last, but by no means least of the Oxford net zero seven. 2 00:00:12,430 --> 00:00:20,890 I'm sitting in for Steve Smith, who is busy recruiting today, so it's all happening with Oxford net zero. 3 00:00:20,890 --> 00:00:28,810 But this is not the last event we're running. So the next major event actually is the formal launch of the programme on May the 7th, 4 00:00:28,810 --> 00:00:34,000 so that the afternoon of May the 7th, where we not only launch the Oxford Net Zero initiative, 5 00:00:34,000 --> 00:00:40,210 but we also launch the university's Oxford University's own sustainability strategy, 6 00:00:40,210 --> 00:00:45,050 and we've got a number of exciting panels and lectures and so forth to mark that event on May the 7th. 7 00:00:45,050 --> 00:00:49,660 So do job by will open. It's going to be virtual, of course, but it's all open to the public. 8 00:00:49,660 --> 00:00:52,960 So do take down in your diary. 9 00:00:52,960 --> 00:01:04,960 But today we have Professor Ross, Abby and Roxana Shafi and Sniffy Gill all talking to us about the role of the oceans in achieving net zero. 10 00:01:04,960 --> 00:01:07,360 This is a really important topic. 11 00:01:07,360 --> 00:01:13,630 The reason I said at the beginning this it's announced in the series only because of diary constraints, not for any other reason. 12 00:01:13,630 --> 00:01:20,800 And so it's clearly going to play an important role in the discussions in COP26 in Glasgow, 13 00:01:20,800 --> 00:01:27,130 as people are starting to weigh up how much of the carbon dioxide generated by our use of fossil fuels. 14 00:01:27,130 --> 00:01:31,840 Can we count on the oceans to mop up? And how can we encourage them to more? 15 00:01:31,840 --> 00:01:38,350 So I think it's going to kick off with just some quick introductions to our speakers. 16 00:01:38,350 --> 00:01:42,970 Ross Rigby is one of the true investigators on the Oxford Zero initiative. 17 00:01:42,970 --> 00:01:54,400 She's a professor of physics of geology in the sciences departments in the university, and she's been working on carbon sequestration, 18 00:01:54,400 --> 00:01:58,300 primarily in the oceans and also the carbon cycle in the oceans on all sorts 19 00:01:58,300 --> 00:02:04,240 of timescales ranging from years to millennia to millions of years for for, 20 00:02:04,240 --> 00:02:08,650 for some quite a while. Actually, I'm not quite sure how long you've been. 21 00:02:08,650 --> 00:02:15,250 I won't say I realise I failed to do my homework on that one. Sorry about that post, but you can tell people how long you been working on this. 22 00:02:15,250 --> 00:02:25,030 And Sophie Gill is a patient in this group, the Ocean Bug Group, and has worked but worked previously for time. 23 00:02:25,030 --> 00:02:27,940 It works and a consulting. 24 00:02:27,940 --> 00:02:37,150 And Roxana Shafi is also a Ph.D. student in the Ocean Bulks Group that is currently seconded to the Scottish Parliament Information Centre. 25 00:02:37,150 --> 00:02:42,220 The ocean is being an important topic for Scotland in the Glasgow cop. 26 00:02:42,220 --> 00:02:53,170 So over to you, Ross. Can I just sorry before we say I'm don't forget, you can ask questions and you can even more importantly, 27 00:02:53,170 --> 00:03:00,280 vote on other people's questions to promote questions that you think are particularly interesting in the course of the talks. 28 00:03:00,280 --> 00:03:05,530 And we'll be picking up on those questions and I'll be sort of feeding them through to the speakers as we go along. 29 00:03:05,530 --> 00:03:13,020 OK. O'Bagy Ross. And I can see your screen now finals. 30 00:03:13,020 --> 00:03:17,970 OK, great. OK, that's fantastic. 31 00:03:17,970 --> 00:03:22,020 Well, thank you, Miles, and thank you, everybody for the opportunity to speak here. 32 00:03:22,020 --> 00:03:29,790 And Miles sort of highlighted, I guess, my my my proclivity, which is that in the end, I'm a geologist by training. 33 00:03:29,790 --> 00:03:39,390 And I guess what I what I want to show you is how we can use the past to perhaps give us hints as to how to make solutions in the future. 34 00:03:39,390 --> 00:03:45,960 And so I'm just showing you here, this is something I guess that inspired the Oxford Net-Zero logo, 35 00:03:45,960 --> 00:03:55,380 and it's a series of different pathways that we may take in terms of emissions to try and hit that net zero at around 2050. 36 00:03:55,380 --> 00:04:04,290 And I guess the key the key point to note, of course, is that all pathways that limit our global warming to 1.5 degrees C predict the use of carbon 37 00:04:04,290 --> 00:04:11,940 dioxide removal on the order of 100 to 1000 billion tons of CO2 over the 21st century. 38 00:04:11,940 --> 00:04:19,470 So that requires some kind of rate of CO2 draw down of one to 10 billion tons of CO2 per year. 39 00:04:19,470 --> 00:04:24,870 Now I'm going to try, and in all of our talks, we we've tried to be consistent with units, 40 00:04:24,870 --> 00:04:28,320 but this is a sort of horrible fit for geochemists is a horrible world. 41 00:04:28,320 --> 00:04:34,140 People talk about gigatons of carbon. Billion tons of carbon masses of CO2. 42 00:04:34,140 --> 00:04:42,120 And I guess the thing to realise is that where you in to convert between tons of carbon and tons of CO2, it's kind of a factor of four. 43 00:04:42,120 --> 00:04:46,770 You're just accounting for the carbon in that CO2 molecule. 44 00:04:46,770 --> 00:04:54,760 But just the numbers to keep in mind are 100 to a thousand gigatons of CO2. 45 00:04:54,760 --> 00:05:04,600 So what's happened already, and I guess the the the key thing about the Asians is that they are already being a major 46 00:05:04,600 --> 00:05:10,120 part of limiting the amount of CO2 that is accumulating in the atmosphere was shown on. 47 00:05:10,120 --> 00:05:14,690 This figure is going from 1750 to around 2010. 48 00:05:14,690 --> 00:05:22,570 A little bit later is the emissions of CO2 from fossil fuel and the cement industry, as well as from land use change. 49 00:05:22,570 --> 00:05:29,980 And you can see those rising up to about 10 a pentagram so gigatons of carbon per year. 50 00:05:29,980 --> 00:05:33,400 When you look beneath that, those kind of horizontal line, 51 00:05:33,400 --> 00:05:40,270 you can see that there is uptake of CO2 in the green zone is what being what's being taken up into 52 00:05:40,270 --> 00:05:46,990 the terrestrial biosphere into some regrowth of the terrestrial biosphere on land in the light blue? 53 00:05:46,990 --> 00:05:53,230 That's the amount of CO2 that is accumulating in the atmosphere. And indeed, is it leading to this global warming? 54 00:05:53,230 --> 00:05:55,930 But in the dark blue, you can see the ocean sink. 55 00:05:55,930 --> 00:06:02,770 So this is how much CO2 is already being taken up into the ocean, and this is occurring because of equilibrium. 56 00:06:02,770 --> 00:06:09,610 The oceans are at equilibrium with the atmosphere, so the more we put into the atmosphere, the more we put into the oceans. 57 00:06:09,610 --> 00:06:16,570 And I guess what we're trying to examine in these next few talks is can we can we manipulate the oceans? 58 00:06:16,570 --> 00:06:26,800 Almost such they take CO2 out of the atmosphere that goes beyond equilibrium, where they are actually actively sequestering that CO2. 59 00:06:26,800 --> 00:06:34,390 Part of the reason that the oceans are so good at sequestering CO2 is because when CO2 dissolves in the ocean, 60 00:06:34,390 --> 00:06:39,400 it reacts and it equilibrate to form the carbonate species in the carbonate species. 61 00:06:39,400 --> 00:06:48,100 And that's shown in this lower panel to the bottom right of the slide here and at a pace of about eight, which is what the oceans are. 62 00:06:48,100 --> 00:06:52,690 The majority of the carbon is existing is by carbonate and carbonate time, 63 00:06:52,690 --> 00:07:00,070 and it's only the sort of small reservoir in the green here of CO2 aqueous that is actually exchanging with the atmosphere. 64 00:07:00,070 --> 00:07:05,920 In terms of quantities, the oceans are already taking up about two gigatons of carbon per year, 65 00:07:05,920 --> 00:07:12,340 and we think that since the start of the industrial revolution, they've taken up about 500 gigatons of CO2 from the atmosphere. 66 00:07:12,340 --> 00:07:20,620 So they're already a good sinkers of CO2. And the question is, can we manipulate that into the future? 67 00:07:20,620 --> 00:07:25,960 And as I've hinted, part of what I want to talk about is the fact that we can take lessons from the past. 68 00:07:25,960 --> 00:07:34,630 And indeed, I started out as a geologist fascinated by glacial interglacial cycles of temperature and atmospheric carbon dioxide and really wanted 69 00:07:34,630 --> 00:07:43,150 to try and get to the bottom of why carbon dioxide seems to breathe in and out of the ocean on these glacial interglacial timescales. 70 00:07:43,150 --> 00:07:49,000 So I'm just showing you in this panel a time scale from 800000 years in the past to the modern day. 71 00:07:49,000 --> 00:07:52,450 And you can see these cycles in temperature in the orange curve here, 72 00:07:52,450 --> 00:07:56,710 where we're changing temperatures by the order of about 10 degrees C and these 73 00:07:56,710 --> 00:08:02,290 are recorded in the ice and in ice cores from Antarctica in the upper curve. 74 00:08:02,290 --> 00:08:06,850 What I'm showing you is is the fluctuations in carbon dioxide in blue here, 75 00:08:06,850 --> 00:08:14,170 and you can see that carbon dioxide this is captured in air bubbles that are being shown in the in the left hand side of this slide. 76 00:08:14,170 --> 00:08:20,500 And they vary on the order of about 100 p.m. between glacial and interglacial time scales. 77 00:08:20,500 --> 00:08:28,090 And you can see that that magnitude of change is almost exactly the same as the amount of CO2 that we put into the atmosphere. 78 00:08:28,090 --> 00:08:35,920 In terms of gigatons of carbon, one ppm is about to gigatons of carbon or eight gigatons of CO2. 79 00:08:35,920 --> 00:08:43,750 And so just from looking at this, we can assume that the glacial ocean is storing about 200 gigatons of carbon from the atmosphere, 80 00:08:43,750 --> 00:08:52,270 purely from the diminishing CO2 in the atmosphere. We point to the ocean as the mechanism behind this because it contains a large 81 00:08:52,270 --> 00:08:56,620 reservoir of carbon that is quite easily interchangeable with the atmosphere. 82 00:08:56,620 --> 00:09:05,170 And so it's able to to therefore breathe out the CO2 and absorb the CO2 on these quite rapid timescales. 83 00:09:05,170 --> 00:09:14,230 And many other reservoirs have have much slower rates of change and are unable to account for these CO2 fluctuations in the same way. 84 00:09:14,230 --> 00:09:18,880 So it's sort of there's been a big community effort. Oh, I should say sorry. 85 00:09:18,880 --> 00:09:23,290 So the glacier world, of course, look very different to the modern day. 86 00:09:23,290 --> 00:09:30,520 And it turns out that we have to account also for the fact that the terrestrial biosphere in a glacier world was very much smaller. 87 00:09:30,520 --> 00:09:37,630 We know at this time about 20000 years ago that ice sheets expanded and covered that large part of northern Europe. 88 00:09:37,630 --> 00:09:42,070 And you can see on this sort of projection looking down on the North Pole of the globe, 89 00:09:42,070 --> 00:09:49,390 you can see England peeking out from the bottom of the ice sheet there in the lower part of that panel. 90 00:09:49,390 --> 00:09:53,860 And of course, this is a time when England couldn't argue whether it was part of Europe or not. 91 00:09:53,860 --> 00:10:02,990 There was. A land connexion between us, so this large ice sheet was covering major parts of the terrestrial biosphere, 92 00:10:02,990 --> 00:10:07,460 and as a result there was there was less carbon being stored there, 93 00:10:07,460 --> 00:10:13,730 and the estimates are that actually this smaller terrestrial biosphere in terms of peat vegetation, 94 00:10:13,730 --> 00:10:22,370 in terms of the soil carbon that was stored was probably around 300 to 700 gigatons of carbon smaller at the glacial times. 95 00:10:22,370 --> 00:10:31,130 So not only did the oceans have to sequester that atmospheric CO2, they also had to store this extra carbon from the terrestrial biosphere. 96 00:10:31,130 --> 00:10:38,630 So that gives us a total glacial ocean storage of about 900 gigatons of carbon, or 30 600 gigatons of CO2. 97 00:10:38,630 --> 00:10:48,830 So this is three to four times more than we need to sequester in the coming century to to hit our 1.5 degrees C target. 98 00:10:48,830 --> 00:10:55,940 Much of what I've worked on, and this is kind of an interesting little message for perhaps for thinking about the 99 00:10:55,940 --> 00:11:02,030 future is that we are all trying to saw what was it explaining this glacial CO2 change, 100 00:11:02,030 --> 00:11:06,110 looking at individual mechanisms and really whether the field has got to now, 101 00:11:06,110 --> 00:11:14,060 is that probably in order to account for that large change in carbon requires a multitude of different mechanisms to do that. 102 00:11:14,060 --> 00:11:19,280 And these rely on the biology, the chemistry and the physics of the glacial ocean. 103 00:11:19,280 --> 00:11:23,870 So just to sort of think about it, how would we draw CO2 down into the ocean? 104 00:11:23,870 --> 00:11:28,220 Well, firstly, I've mentioned that the surface ocean is at equilibrium with the atmosphere, 105 00:11:28,220 --> 00:11:34,550 and so we would need to somehow shift that equilibrium more towards CO2 being dissolved in the surface ocean. 106 00:11:34,550 --> 00:11:40,670 We can do that by raising the edge of the ocean, by lowering the temperature or by lowering the salinity. 107 00:11:40,670 --> 00:11:47,000 And those those effects have the impact of drawing CO2 down via changing the equilibrium, 108 00:11:47,000 --> 00:11:51,450 the additional parts that could be manipulated as the power of the biological pump. 109 00:11:51,450 --> 00:11:55,910 So we have a whole ton of organisms photosynthesising in the surface waters. 110 00:11:55,910 --> 00:12:03,380 They remove carbon dioxide into their organic matter and they drop down into the deep ocean and they take that carbon dioxide with them. 111 00:12:03,380 --> 00:12:11,450 So if they remove more CO2 from the surface ocean, that has also has the impact of sequestering carbon in the deep ocean. 112 00:12:11,450 --> 00:12:14,750 These are all set against the physics that ocean overturning. 113 00:12:14,750 --> 00:12:22,430 So how rapidly perhaps CO2 water's being taken down into the deep ocean via this mixing that occurs in the 114 00:12:22,430 --> 00:12:30,020 ocean versus the rate of upwelling of CO2 in the ocean or sorry of carbon rich waters from from beneath. 115 00:12:30,020 --> 00:12:34,400 So these are the sorts of dials that we could think about changing in the glacial ocean, 116 00:12:34,400 --> 00:12:40,700 and there are proxies, various ways of indirect ways of trying to tease apart these different mechanisms. 117 00:12:40,700 --> 00:12:51,170 And what I'm just showing here is is a is a model which tries to piece together how each of these different mechanisms contributed to changing CO2. 118 00:12:51,170 --> 00:12:56,510 So I'll control run has about two hundred and eight tpmf of CO2. 119 00:12:56,510 --> 00:13:00,830 If we then allow the ocean to cool and increase the solubility of CO2, 120 00:13:00,830 --> 00:13:05,870 as well as having that cooling impact change the circulation pattern of the ocean 121 00:13:05,870 --> 00:13:12,260 that takes down about half of the glacial CO2 if we then allow nutrient addition. 122 00:13:12,260 --> 00:13:18,740 And this is something that Sophie will talk about in some detail. The kind of impacts of the fact that we know the glacial world was dustier. 123 00:13:18,740 --> 00:13:28,640 There was more iron which fertilised that biological pump of carbon that can remove almost the other half of the glacial CO2. 124 00:13:28,640 --> 00:13:35,750 But then if we if we take the land carbon reduction and put that back into the ocean, that makes the CO2 go back up. 125 00:13:35,750 --> 00:13:44,120 So we're now at 2:15 p.m. We then lower the sea level, which raises the salinity of the ocean. 126 00:13:44,120 --> 00:13:47,330 And that again adds to the CO2 in the atmosphere. 127 00:13:47,330 --> 00:13:54,050 And the final part that needs to occur to sort of reach our glacial target almost is the fact that the lowering 128 00:13:54,050 --> 00:14:00,950 of that sea level eliminates all the shelf area with things like calcium carbonate or accumulating in corals, 129 00:14:00,950 --> 00:14:05,900 and that calcium carbonate then builds up in the ocean as sort of alkaline et al. 130 00:14:05,900 --> 00:14:12,410 Colonisation of the ocean. And that allows us to then reach a sort of final glacial CO2 target. 131 00:14:12,410 --> 00:14:21,260 So these are the sorts of dials that have contributed to explaining this total CO2 drawdown. 132 00:14:21,260 --> 00:14:31,100 So and indeed, we've had we've got proxies which can both tell us about the quantity of CO2 that was was taken into the ocean, 133 00:14:31,100 --> 00:14:41,480 as well as the impacts of it. And so what I'm showing here is is a reconstruction that we've made using a new proxy for deep ocean oxygen. 134 00:14:41,480 --> 00:14:47,330 Now the great thing about being able to reconstruct deep ocean oxygen is it allows us to quantify 135 00:14:47,330 --> 00:14:54,200 how much CO2 is has been taken into the ocean via the process at the biological pump and via. 136 00:14:54,200 --> 00:15:02,270 Ratification, both of which remove oxygen from the seawater, so any biological mechanism which lowers CO2. 137 00:15:02,270 --> 00:15:10,400 The fact that we're making more organic matter means that it has to be respected and it demands and takes out oxygen from the water column. 138 00:15:10,400 --> 00:15:16,250 And so we've been able to show that the response and carbon concentrations are much higher in the glacial ocean. 139 00:15:16,250 --> 00:15:22,820 And indeed, that biological pump mechanism accounts for about a third of the glacial CO2 storage, 140 00:15:22,820 --> 00:15:30,390 but also gives us much lower oxygen concentrations across the Atlantic and in the deep Pacific. 141 00:15:30,390 --> 00:15:37,140 So that's the additional impact that we can see of these mechanisms is that we know that 142 00:15:37,140 --> 00:15:42,330 the glass relation had a higher rate again because of that addition of the calcium 143 00:15:42,330 --> 00:15:48,060 carbonate from the loss of the corals and the impact of that on the remaining calcify as 144 00:15:48,060 --> 00:15:53,400 the pelagic calcified of the forum and from the calligraphers is that they calcify more. 145 00:15:53,400 --> 00:16:00,180 We have records where the mass of these their calcite shells increases as you go into glacial periods. 146 00:16:00,180 --> 00:16:08,130 So this gives us some insight into the impact of these different sequestration processes on the biota that's living there. 147 00:16:08,130 --> 00:16:13,590 And just a final slide, a sort of alarming component, perhaps of the lower oxygen, 148 00:16:13,590 --> 00:16:18,150 which would undoubtedly impact the microbes that are living in the ocean in terms 149 00:16:18,150 --> 00:16:23,910 of the larger organisms and the diversity of organisms living in the deep ocean. 150 00:16:23,910 --> 00:16:27,510 We don't have good diversity measures across the global ocean, 151 00:16:27,510 --> 00:16:32,850 but our general understanding is that the diversity of benthic fauna correlates 152 00:16:32,850 --> 00:16:38,040 with bottom water temperatures where a colder ocean leads to lower diversity. 153 00:16:38,040 --> 00:16:45,420 But it also correlates with productivity in the surface ocean and the rain of organic carbon, essentially providing food to the deep ocean. 154 00:16:45,420 --> 00:16:51,360 And so, of course, in the glaciation, these things are working in different directions. Colder temperatures give us lower diversity, 155 00:16:51,360 --> 00:16:56,460 but we certainly have evidence that the biological pump was stronger and that could have fuelled higher diversity. 156 00:16:56,460 --> 00:17:05,250 But it would seem that that generally that the diversity is less controlled by oxygen availability and more so by this rain of organic carbon. 157 00:17:05,250 --> 00:17:09,360 So I guess what I wanted to show you was that the glacial ocean gives us more than 158 00:17:09,360 --> 00:17:14,970 the capacity required to account for to try and sequester CO2 going into the future. 159 00:17:14,970 --> 00:17:21,510 And it gives us these hints at potential impacts of differing mechanisms on the fauna that is already living there. 160 00:17:21,510 --> 00:17:29,000 And I'll leave you there and let Sophie take over. Thank you very much, Ross. 161 00:17:29,000 --> 00:17:32,870 And some some really intriguing hints there about the potential here. 162 00:17:32,870 --> 00:17:38,090 We're going to hear from all three speakers and then go to questions, but do keep the questions coming. 163 00:17:38,090 --> 00:17:44,490 Apologies for my question, but I'm still intrigued by it. So when we're getting on to. 164 00:17:44,490 --> 00:17:51,380 So whenever he's finished speaking. But if you've got if you've got a specific technical question for the speakers, do you highlight it? 165 00:17:51,380 --> 00:17:55,820 And I'll try and answer that as we go along. Just give it up. Okay, so over to you. 166 00:17:55,820 --> 00:18:01,910 Sophie, next. Oh, great. 167 00:18:01,910 --> 00:18:10,510 I can hear you now. Right? And you're just going to share your screen, and it seems to be sharing. 168 00:18:10,510 --> 00:18:14,700 Okay, well then Sophia. Fantastic. Thank you. 169 00:18:14,700 --> 00:18:23,850 So I'm going to introduce the proposed methods to you artificially enhance a magnitude or accelerate the rate of carbon 170 00:18:23,850 --> 00:18:29,850 storage in today's oceans to actually draw down the carbon dioxide that's already in the atmosphere from prior emissions. 171 00:18:29,850 --> 00:18:33,360 And many of these take their inspiration from the kind of oceans physical, 172 00:18:33,360 --> 00:18:38,660 chemical and biological systems that have operated differently in the geological past, as Ross has outlined. 173 00:18:38,660 --> 00:18:42,270 And so here is a kind of family tree, if you like, 174 00:18:42,270 --> 00:18:49,680 as proposed ocean based carbon dioxide removal techniques often referred to as Ocean CD-RW techniques. 175 00:18:49,680 --> 00:18:57,630 And these CD-RW techniques can be broadly split into those which aim to increase the carbon removal capacity of the oceans abiotic pumps. 176 00:18:57,630 --> 00:19:03,210 So the physical and chemical aspects of how the ocean works or the ocean's biological pumps, 177 00:19:03,210 --> 00:19:06,630 so influencing the biology of the oceans store more carbon. 178 00:19:06,630 --> 00:19:12,690 And I think Roxana is going to dive into blue carbon management in more detail, but just to briefly touch on it here. 179 00:19:12,690 --> 00:19:19,980 In many cases, it's not technically considered to be a carbon removal scheme as a blue carbon. 180 00:19:19,980 --> 00:19:24,360 Habitats like mangroves, grasses, etc., a large source of CO2. 181 00:19:24,360 --> 00:19:29,520 But unless these habitats are specifically being expanded, so drawing down more carbon than they currently are. 182 00:19:29,520 --> 00:19:35,160 This doesn't really count as carbon dioxide removal. So let's outline each of the techniques for this family tree now. 183 00:19:35,160 --> 00:19:44,280 What are they and what's their cedar potential? So artificial dwelling means to stimulate enhanced downward transport of cold CO2, 184 00:19:44,280 --> 00:19:52,990 saturated downward transport surface waters down to the deep ocean for storage of up to hundreds, or potentially even thousands of years. 185 00:19:52,990 --> 00:19:58,290 And this technique is really still in its infancy in terms of peer reviewed research. 186 00:19:58,290 --> 00:20:01,710 So there's no real good estimates of its potential yet. 187 00:20:01,710 --> 00:20:08,340 But moving on to community enhancement, and this is a scheme that aims to add alkaline materials to the surface ocean, 188 00:20:08,340 --> 00:20:12,540 either directly or through enhanced weathering or electrochemical production to 189 00:20:12,540 --> 00:20:16,800 increase the CO2 solubility in seawater through the Surface Oceans buffer system, 190 00:20:16,800 --> 00:20:24,930 which rules kind of outlined previously. And this technique has the potential to store up to one gigatons of carbon per year, 191 00:20:24,930 --> 00:20:31,970 or the equivalent of about three point six seven gigatons of carbon dioxide per year. 192 00:20:31,970 --> 00:20:37,130 And moving on to deep storage, this aims to make use of the department store carbon rich material, 193 00:20:37,130 --> 00:20:46,910 either by injecting CO2 directly into the deep water layers of the ocean or by injecting liquid CO2 into marine geological reservoirs. 194 00:20:46,910 --> 00:20:51,650 And this is a difficult one to quantify because it varies a bit depending on location. 195 00:20:51,650 --> 00:20:59,900 But it's been estimated that for basaltic rocks offshore Iceland and we could store a wide range really hit for the estimate, 196 00:20:59,900 --> 00:21:05,280 but between 60 to seven thousand gigatons of carbon dioxide total. 197 00:21:05,280 --> 00:21:10,680 So ocean fertilisation means addition of nutrients to stimulate primary production, 198 00:21:10,680 --> 00:21:17,850 whether that be using the micronutrient iron or the macronutrients, nitrogen and or phosphorus. 199 00:21:17,850 --> 00:21:22,530 And the CDC estimates vary slightly depending on which method of nutrient addition 200 00:21:22,530 --> 00:21:27,750 is used and iron addition is by far the most research pathway of the two. 201 00:21:27,750 --> 00:21:34,650 Iron Edition makes up the vast majority of literature on ocean CDR techniques because there were actually 10 to 15 202 00:21:34,650 --> 00:21:42,060 mesoscale iron enrichment experiments that were carried out in different areas of the global ocean since the early 1990s. 203 00:21:42,060 --> 00:21:49,170 And the consensus, I think nowadays is that this technique doesn't really have the potential to be deployed due to the myriad of disruptive 204 00:21:49,170 --> 00:21:57,250 effects on ecosystems and issues with production of climate relevant gases like nitrous oxide or dimethyl sulphide. 205 00:21:57,250 --> 00:22:01,680 And these effects were established relatively early on in the timeline of these experiments being wrong. 206 00:22:01,680 --> 00:22:10,110 So I would argue we can learn how to more quickly produce relevant data for Ocean CD-RW using iron fertilisation as a kind of case 207 00:22:10,110 --> 00:22:18,150 study and artificial upwelling works in a similar way to ocean fertilisation and supplying nutrients to simulate primary production. 208 00:22:18,150 --> 00:22:26,070 But instead of adding nutrients to the surface ocean directly, we do it by enhancing oakwood transport of nutrient rich waters. 209 00:22:26,070 --> 00:22:32,520 And this has potential to store between nought point two to eight point nine gigatons of carbon per year. 210 00:22:32,520 --> 00:22:38,400 And finally, microbial cultivation makes use of macroalgae to remove carbon dioxide from 211 00:22:38,400 --> 00:22:43,170 surface waters through organic carbon export and through the sinking of biomass. 212 00:22:43,170 --> 00:22:50,700 And and there's a slightly lower carbon at sorry carbon storage estimate for this technique than the others. 213 00:22:50,700 --> 00:22:58,230 But arguably, macro algal cultivation comes with less technological barriers and kind of fewer potential ecosystem impacts. 214 00:22:58,230 --> 00:23:04,650 And I think something we see often with these CD-RW techniques is the higher the risk of unintended or should I probably 215 00:23:04,650 --> 00:23:11,410 say as yet unknown impacts for many of the techniques and potentially the high the reward in terms of carbon removal. 216 00:23:11,410 --> 00:23:15,480 And so there's that kind of risk reward trade-off there. 217 00:23:15,480 --> 00:23:18,480 And for the combined sea, the potential of all of these techniques, 218 00:23:18,480 --> 00:23:24,060 taken together is around six point four gigatons per year based on the available data, 219 00:23:24,060 --> 00:23:30,870 plus the geological storage potential of deep storage and geological reservoirs, which as we saw, was potentially pretty sizeable. 220 00:23:30,870 --> 00:23:35,250 But the estimates vary dependent on location and we're also it's somewhere 221 00:23:35,250 --> 00:23:39,030 between one to 10 gigatons of carbon per year is what we need to be aiming for. 222 00:23:39,030 --> 00:23:45,810 So this looks pretty good in terms of the potential for the ocean. But actually, this includes the figure for iron fertilisation here, which, 223 00:23:45,810 --> 00:23:50,250 as I said, I think he's incredibly unlikely to be ruled out as a seed scheme. 224 00:23:50,250 --> 00:23:54,930 So it's evident that no single one of these techniques will be enough kind of on its own. 225 00:23:54,930 --> 00:24:01,200 We'll probably need a full portfolio of these techniques operating together to meet international carbon removal targets. 226 00:24:01,200 --> 00:24:07,200 And aside from ocean iron fertilisation, we don't have enough data about any of the other schemes, even our C enhancement, 227 00:24:07,200 --> 00:24:13,710 which is by far the next most researched technique to be able to make informed decisions about their deployment. 228 00:24:13,710 --> 00:24:23,310 So we need to get moving on, generating the most relevant data for these schemes quickly and efficiently and to progress research in this area. 229 00:24:23,310 --> 00:24:30,150 We really need to learn from the case of the iron fertilisation so we can identify that for any seed scheme. 230 00:24:30,150 --> 00:24:35,760 There are kind of three priority research questions which everyone researching these schemes should be trying to answer. 231 00:24:35,760 --> 00:24:45,270 So I've listed them here, and I think number three can also be extended beyond science to kind of include governance, economics and social science. 232 00:24:45,270 --> 00:24:50,910 And even after the huge, amazing scientific effort that we saw with iron fertilisation research, 233 00:24:50,910 --> 00:24:54,060 we're still not sure where the iron fertilisation really answers the second point 234 00:24:54,060 --> 00:24:58,890 here whether it resulted in increased carbon export and storage in the deep ocean. 235 00:24:58,890 --> 00:25:04,240 And that's a key barrier to decisions concerning its deployment. 236 00:25:04,240 --> 00:25:11,860 So just touching briefly on my personal research, I'm trying to establish where the calcifying plankton, so those which make their peaceful, 237 00:25:11,860 --> 00:25:20,360 intricate shells out of calcium carbonate pictured here we have a chocolate for under foreign minister. 238 00:25:20,360 --> 00:25:23,990 Outside, as a by-product of increasing their calcium carbonate production, 239 00:25:23,990 --> 00:25:29,660 if we add extra alkalinity to the ocean and also whether there are any potential damaging 240 00:25:29,660 --> 00:25:34,970 impacts on these calcified in their role as a major component in the Ocean's ecosystem. 241 00:25:34,970 --> 00:25:38,870 And so my research is kind of currently a work in progress. 242 00:25:38,870 --> 00:25:42,650 It's unpublished at the moment. I'm still working on it, I still doing my Ph.D., 243 00:25:42,650 --> 00:25:46,850 but I've been able to show that there's a potential increase in calcification as 244 00:25:46,850 --> 00:25:52,520 a result of alkalinity enhancement via a couple of different chemical pathways. 245 00:25:52,520 --> 00:25:57,350 And it but it may be that this increase is no greater than the decrease in calcium carbonate 246 00:25:57,350 --> 00:26:02,120 production we've seen as a result of ocean acidification over the last few years, 247 00:26:02,120 --> 00:26:07,400 as we've we've had the impacts of anthropogenic climate change actually on the ocean. 248 00:26:07,400 --> 00:26:10,700 And this is something I'm currently trying to unpick. 249 00:26:10,700 --> 00:26:18,170 But just to kind of round off what are the things that we need to move forward and achieve an ocean that looks something a little bit like this, 250 00:26:18,170 --> 00:26:26,810 even if not completely fulfilling all of these kind of check points of different carbon removal strategies. 251 00:26:26,810 --> 00:26:32,280 But how do we move towards achieving some enhanced carbon sinks? So I think there's two major things. 252 00:26:32,280 --> 00:26:39,710 First one is that we need a coordinated, prioritised research strategy framework within which to operate. 253 00:26:39,710 --> 00:26:44,960 And secondly, we need coordination between sectors which will enable these decisions about 254 00:26:44,960 --> 00:26:49,160 deployment of these schemes to be assessed in a kind of safe and responsible way. 255 00:26:49,160 --> 00:26:57,200 And also, like I said, generate the data in the most efficient way possible to answer the questions that that we need to know the answer to. 256 00:26:57,200 --> 00:27:05,270 And so, yeah, over the rocks on it to tell us a little bit more about kind of blue carbon stores, I think. 257 00:27:05,270 --> 00:27:12,890 Thank you very much, Sophie. Yes, and if we didn't see any very specific questions for Sophie, so I'll sort of keep logging the questions, 258 00:27:12,890 --> 00:27:22,320 keep them coming, keep voting for other people's questions and overdue Roxana. 259 00:27:22,320 --> 00:27:28,800 All right, well, thank you, Roz and Sophie, for that. I think you've set the stage really well, that's what I'm about to say. 260 00:27:28,800 --> 00:27:32,760 Just to reiterate, as Miles said, My name is Roxana Shafi. 261 00:27:32,760 --> 00:27:40,920 I'm a DPhil researcher at the University of Oxford and currently on the research to comment to the Scottish Parliament Research Centre, 262 00:27:40,920 --> 00:27:45,390 where I'm working on a policy briefing on blue carbon. So I've put my email and Twitter there. 263 00:27:45,390 --> 00:27:50,670 Please feel free to ask me any questions if I don't get around to answering them today for you, 264 00:27:50,670 --> 00:27:55,560 and I'm always keen to chat more about the science, of course. 265 00:27:55,560 --> 00:28:05,460 So the term blue carbon really came into existence in 2009 and following on from this key report compiled by a number of institutions and experts and 266 00:28:05,460 --> 00:28:13,560 the central aim of this piece of work was to draw policymakers attention to the vast quantities of carbon which is stored in the marine environment. 267 00:28:13,560 --> 00:28:19,590 And this is against the backdrop of the policy landscape that was primarily focussed on land based ecosystems. 268 00:28:19,590 --> 00:28:27,150 So in order to do this, the authors coined the metaphor blue carbon to describe carbon stored in marine and coastal ecosystems, 269 00:28:27,150 --> 00:28:32,040 and green currents describe carbon in land based habitats such as forests. 270 00:28:32,040 --> 00:28:37,440 So some of the main definitions will perhaps focus more on coastal habitats and species. 271 00:28:37,440 --> 00:28:44,670 And this is the carbon which is stored in the living biomass and the underlying soils and sediments of coastal habitats like mangroves, 272 00:28:44,670 --> 00:28:53,070 salt marshes, sea grasses and kelp. And the reason that they typically tend to be at the forefront of this blue carbon definition is because 273 00:28:53,070 --> 00:28:59,310 they're the things that can be managed on a policy scan a national scale a bit more easily than perhaps, 274 00:28:59,310 --> 00:29:03,270 for instance, carbon stored in the oceans globally. 275 00:29:03,270 --> 00:29:08,220 But as a as has been mentioned that the carbon which is stored across the oceans 276 00:29:08,220 --> 00:29:14,220 on seafloor sediments has also been incorporated into this definition of carbon. 277 00:29:14,220 --> 00:29:18,960 So when we're talking about blue carbon, how significant are these stores? 278 00:29:18,960 --> 00:29:25,080 So there's an emerging evidence base to show that blue carbon actually exceeds what we call trading carbon. 279 00:29:25,080 --> 00:29:31,590 And this is predominantly because of the vast quantities of carbon which is stored on sea seafloor sediments, 280 00:29:31,590 --> 00:29:35,710 so they store a whopping three thousand one hundred seventeen billion tonnes. 281 00:29:35,710 --> 00:29:39,720 So billion tonnes is equivalent to gigatons and that we've been kind of switching between 282 00:29:39,720 --> 00:29:46,380 the two and coastal habitats contribute quite a lot less around forty five billion tonnes, 283 00:29:46,380 --> 00:29:51,000 but still very important in terms of the ecosystem benefits. 284 00:29:51,000 --> 00:29:57,030 So given that kind of quick whistle stop tour of what sort of quantities are we talking about here? 285 00:29:57,030 --> 00:30:03,420 How can we start thinking about blue carbon in terms of policy frameworks for climate change mitigation? 286 00:30:03,420 --> 00:30:06,330 And there's really two ways that we can do this. The first of all, 287 00:30:06,330 --> 00:30:11,970 we can think about this is the imperative to preserve blue carbon habitats so they don't release more 288 00:30:11,970 --> 00:30:18,150 carbon and make climate change a big issue and so that they can continue sequestering carbon in the future. 289 00:30:18,150 --> 00:30:23,160 And the second way of thinking about blue carbon habitats in this kind of chimes more into what 290 00:30:23,160 --> 00:30:29,670 Sophie was speaking about earlier is in terms of restoring and creating more of these environments. 291 00:30:29,670 --> 00:30:34,710 They actually enhance and increase carbon sequestration and storage. 292 00:30:34,710 --> 00:30:39,500 So in terms of the preservation of these environments? 293 00:30:39,500 --> 00:30:46,430 There is now a significant body of knowledge to show that human activities are causing damage to known carbon stores. 294 00:30:46,430 --> 00:30:47,120 For instance, 295 00:30:47,120 --> 00:30:54,860 now it's predicted that around 1.3 percent of the ocean floor is trawled annually and trawling is a type of bottom towed fishing practise, 296 00:30:54,860 --> 00:31:00,440 which involves tracking a net or a heavy steel frame along the ocean floor in order to catch fish. 297 00:31:00,440 --> 00:31:08,180 And as you can kind of see here, this physically disturbs the sediment and can release the carbon into the overlying water column. 298 00:31:08,180 --> 00:31:15,500 And the second way that this kind of mostly affects coastal areas is coastal land developments, where they're physically clearing these regions. 299 00:31:15,500 --> 00:31:20,950 So it's not predicted that half of the world's mangrove habitats have been lost because of coastal 300 00:31:20,950 --> 00:31:27,870 land developments and the scale of carbon release from these activities is not insignificant. 301 00:31:27,870 --> 00:31:37,640 And trawling and coastal habitat loss actually has recently been discovered to release more carbon dioxide emissions than the aviation industry. 302 00:31:37,640 --> 00:31:45,560 And on the same order of magnitude as deforestation. So the second way that we can think about blue carbon, as I alluded to, 303 00:31:45,560 --> 00:31:51,980 is how can we use these ecosystems in order to increase carbon sequestration and storage? 304 00:31:51,980 --> 00:31:56,750 And it's estimated that if we were to restore wetlands globally, 305 00:31:56,750 --> 00:32:03,410 we could potentially have 40 percent of the needed mitigation mitigation potential to maintain global temperature rise 306 00:32:03,410 --> 00:32:09,860 within two degrees C above pre-industrial levels and blue carbon environments are often thought of as a really attractive, 307 00:32:09,860 --> 00:32:16,380 nature based solution, and nature based solutions was the focus of one of the previous net zero series. 308 00:32:16,380 --> 00:32:18,770 So I would really recommend go back and look at that. 309 00:32:18,770 --> 00:32:25,010 If you're if you're interested in nature based solutions and these are solutions refers to the sustainable management 310 00:32:25,010 --> 00:32:31,070 and use of nature for tackling socio environmental challenges and particularly focussed on climate change. 311 00:32:31,070 --> 00:32:35,690 And the reason that blue carbon is often seen as an attractive solution is because if you were 312 00:32:35,690 --> 00:32:39,860 to take a metre squared of blue carbon environment like seagrass or something like that, 313 00:32:39,860 --> 00:32:46,880 and then compare it with its equivalent green carbon environment, oftentimes the blue carbon environments sequester more, 314 00:32:46,880 --> 00:32:51,890 so they capture more carbon dioxide out of the atmosphere permanent metre squared yet. 315 00:32:51,890 --> 00:32:56,780 So this is some of the data that we've been looking at the Scottish Parliament showing that Scotland's blue 316 00:32:56,780 --> 00:33:04,790 carbon environments are often able to sequester more carbon dioxide than the equivalent land based ecosystems. 317 00:33:04,790 --> 00:33:13,460 And while we can kind of think back to the carbon storage of these ecosystems and perhaps the restoration and enhancement of coastal habitats, 318 00:33:13,460 --> 00:33:18,440 it's not going to be the panacea for being able to sequester all the carbon dioxide that 319 00:33:18,440 --> 00:33:24,160 we need to and some of the figures that have emerged earlier from some of the talks. 320 00:33:24,160 --> 00:33:30,800 And it's one piece of the puzzle, and it can't be understated how important restoring some of these ecosystems are, 321 00:33:30,800 --> 00:33:34,160 and especially from a climate change adaptation perspective, 322 00:33:34,160 --> 00:33:43,730 because coastal ecosystems are hugely important in increasing the resilience to climate change effects which are already being observed. 323 00:33:43,730 --> 00:33:50,090 So a decade on from the first kind of initial coining of the blue carbon term, this metaphor, 324 00:33:50,090 --> 00:33:59,480 where have we gotten from a policy perspective, what's being done about them considering these ecosystems and climate change mitigation? 325 00:33:59,480 --> 00:34:05,750 So 28 countries include blue carbon in their mitigation actions in their nationally determined contributions. 326 00:34:05,750 --> 00:34:11,570 And these are the specific efforts that are being made by countries to reduce national emissions 327 00:34:11,570 --> 00:34:16,430 and adapt to the impacts of climate change in response to the Paris Climate Agreement. 328 00:34:16,430 --> 00:34:20,930 And 59 countries include blue carbon in their adaptation strategies. 329 00:34:20,930 --> 00:34:31,520 And this has largely been mediated by the IPCC frameworks, including wetlands, into policy into greenhouse gas emissions inventories. 330 00:34:31,520 --> 00:34:35,720 But this does only relate to salt marshes, mangroves and seagrasses. 331 00:34:35,720 --> 00:34:41,000 So lots of other habitats which could potentially sequester high amounts of carbon are not being included. 332 00:34:41,000 --> 00:34:47,060 COP26 Climate Convention and biodiversity themed convention opportunities to 333 00:34:47,060 --> 00:34:52,460 raise the profile of blue carbon and increase momentum and keep it going on. 334 00:34:52,460 --> 00:34:57,950 But I've kind of just want to throw out to you at the end of some food for thought, 335 00:34:57,950 --> 00:35:04,040 given the emerging evidence based I presented here is this blue carbon policy world moving quickly enough, 336 00:35:04,040 --> 00:35:08,960 especially in contrast to what we know about terrestrial environments and how it developed 337 00:35:08,960 --> 00:35:14,540 the policies for terrestrial based ecosystems in terms of climate change mitigation. 338 00:35:14,540 --> 00:35:21,530 So I'd be happy to discuss this more. And yeah, thank you very much for listening. 339 00:35:21,530 --> 00:35:31,490 Well, thank you again and thank you all. That was a great series of talks and lots of questions coming in, so hopefully we'll back up on screen. 340 00:35:31,490 --> 00:35:43,100 Good to see you all. And I there was the sort of those one question which is, which is come through is everybody's excited to hear about this. 341 00:35:43,100 --> 00:35:50,120 I mean, this this fundamental question about, you know, if we start using the oceans in this way, 342 00:35:50,120 --> 00:35:52,790 any activity in the oceans which come that comes into Robert, 343 00:35:52,790 --> 00:35:59,990 Chris, by the way, any active in the oceans at climatically significant scale will have undesirable ecosystem consequences. 344 00:35:59,990 --> 00:36:05,120 And do we have know enough about the oceans to be confident about this? 345 00:36:05,120 --> 00:36:07,760 And can we get that knowledge fast enough in order to be able to use it? 346 00:36:07,760 --> 00:36:15,830 So so what what are the implications of sort of as it were using the oceans to mop up fossil carbon? 347 00:36:15,830 --> 00:36:23,240 He wants to take that one to start with. I guess we should have known this for me warming? 348 00:36:23,240 --> 00:36:34,430 Yes. I mean, I think the one thing I'd say this thinking from an ocean alkalinity enhancement perspective is that we 349 00:36:34,430 --> 00:36:41,780 have already detrimentally impacted the ocean and its chemistry by emitting the CO2 that we have so far. 350 00:36:41,780 --> 00:36:50,210 We know that the edge of the ocean has declined and there is alarm about ocean acidification. 351 00:36:50,210 --> 00:36:56,720 And so I think in terms of, in a way, part of the manipulation of ocean chemistry. 352 00:36:56,720 --> 00:37:06,740 If we think just of P.H. and raising alkalinity, part of that could be considered in the sense that we're restoring it to where it was. 353 00:37:06,740 --> 00:37:13,130 And if we can do it in such a way that we're not adding a whole ton of other impurities 354 00:37:13,130 --> 00:37:20,780 that I think that the the ecosystem impacts of that could only be a good thing. 355 00:37:20,780 --> 00:37:27,920 Whether we can do that in a in a in scale, in a way that is acceptable, that's that's another question. 356 00:37:27,920 --> 00:37:33,170 So I guess I guess I feel that part is is OK. 357 00:37:33,170 --> 00:37:39,560 I agree that. But I think there are many possibilities within SoFi's schemes. 358 00:37:39,560 --> 00:37:51,830 Things like putting liquid CO2 down into the bottom of the ocean and I suspect, would probably not have major impacts on the biota. 359 00:37:51,830 --> 00:37:56,840 But maybe, Sophie, do you want to say a bit more about which which of the techniques you thinking? 360 00:37:56,840 --> 00:38:04,910 And I guess what we what we learnt from the glacial ocean again, I suppose that's what I was really trying to figure out is that yes, 361 00:38:04,910 --> 00:38:10,820 there may be impacts on calcify as associated with alkalinity enhancement. 362 00:38:10,820 --> 00:38:17,480 And but in terms of biodiversity of the fauna in the deep ocean, 363 00:38:17,480 --> 00:38:25,610 I'm not sure we could see big impacts of that from this much larger than a three fold greater CO2 sequestration in the glaciation. 364 00:38:25,610 --> 00:38:29,810 I guess that's what I want to say. So if you do have more to add on that, yeah, 365 00:38:29,810 --> 00:38:37,820 I just I think you've kind of said most of the things that I would want to highlight and the main one being that particularly so iron fertilisation, 366 00:38:37,820 --> 00:38:42,230 we do know that there are potentially a myriad of kind of unintended consequences. 367 00:38:42,230 --> 00:38:47,030 But. Like I said, I think that is very unlikely to be rolled out was a feeder scheme for those reasons, 368 00:38:47,030 --> 00:38:53,390 and actually the hope is that we would do the research to make sure that that won't happen. 369 00:38:53,390 --> 00:38:59,330 We will never roll anything out where we think there will be significant disruption of ecosystems. 370 00:38:59,330 --> 00:39:04,610 However, the ecosystems are being disrupted because of ocean acidification at the moment. 371 00:39:04,610 --> 00:39:13,460 So if we don't do anything, then they're not going to, then they're not going to kind of survive the pressure that we're putting on them. 372 00:39:13,460 --> 00:39:19,910 So especially with ocean alkalinity enhancement, which is the scheme that I work on, yeah, 373 00:39:19,910 --> 00:39:27,650 I think there's enormous potential to reverse the damaging effects of ocean acidification as well as drawing down extra carbon dioxide. 374 00:39:27,650 --> 00:39:34,190 And there are natural analogues in the present day as well, not just in the kind of past oceans. 375 00:39:34,190 --> 00:39:39,380 For example, the Black Sea is actually a naturally high alkalinity ocean, 376 00:39:39,380 --> 00:39:46,250 and that ecosystem functions pretty normally compared to other ecosystems in the ocean, just a much higher alkalinity. 377 00:39:46,250 --> 00:39:53,120 And there is a kind of a much higher calcification budget in that ocean. 378 00:39:53,120 --> 00:39:57,380 So there is some evidence that more calcium carbonate production happens there. 379 00:39:57,380 --> 00:40:03,080 However, the ecosystem isn't completely thrown out of whack by just being a naturally hierarchical and sea. 380 00:40:03,080 --> 00:40:06,890 So I think there's a lot of potential for that technique, and to be honest, the other techniques. 381 00:40:06,890 --> 00:40:13,790 I can't massively speak to the unintended impacts yet because there's just not been the research done. 382 00:40:13,790 --> 00:40:19,430 But like I said, hopefully in the coming years, we will we will know a bit more. 383 00:40:19,430 --> 00:40:24,830 Just look solid. Can I just ask you because you're dealing directly with politicians and moment at the moment? 384 00:40:24,830 --> 00:40:33,650 Do you do you find that politicians are sort of there are certain kinds of interventions that are just a no-no for people? 385 00:40:33,650 --> 00:40:40,890 I mean, people open to the idea of being carbon storage or is it just a mystery to people? 386 00:40:40,890 --> 00:40:43,970 And what are you finding? And most definitely. 387 00:40:43,970 --> 00:40:48,890 And I think that's because blue carbon is especially with the restoration of some of these environments, 388 00:40:48,890 --> 00:40:54,710 which have been damaged in the past, is seen as a almost a low risk strategy. 389 00:40:54,710 --> 00:40:59,630 And perhaps the sequestration potential isn't as high as some of these geoengineering techniques. 390 00:40:59,630 --> 00:41:07,910 But given the multitude of benefits in terms of biodiversity, which has implications for water quality tourism, all these different things, 391 00:41:07,910 --> 00:41:14,690 it's a kind of a win win solutions for policymakers, the kind of, I guess, 392 00:41:14,690 --> 00:41:19,700 when it comes to the big quantities of carbon and we are discussing just a bit earlier, 393 00:41:19,700 --> 00:41:25,460 some of that seems to be a kind of a higher risk reward sort of scenario in terms of sequestration, 394 00:41:25,460 --> 00:41:31,220 whereas these big carbon environments perhaps not going to be the the thing that the 395 00:41:31,220 --> 00:41:36,500 solution to these problems that have a lot of other benefits in terms of climate change, 396 00:41:36,500 --> 00:41:45,090 adaptation and resilience. And how does the Scottish Government react to the suggestion we should ban trawling? 397 00:41:45,090 --> 00:41:50,850 I think you have to say with this, perhaps not so much the government, but the fishing industry. 398 00:41:50,850 --> 00:41:55,350 Yeah, it's the balance is a tension of balance. It's a tension between different industries. 399 00:41:55,350 --> 00:42:00,540 You you use the ocean and make their living from it. And also, we want to protect the biodiversity. 400 00:42:00,540 --> 00:42:09,450 And of course, it's in it's in everybody's interest to protect the Biodiversity Fund from an economic perspective, sustainability perspective. 401 00:42:09,450 --> 00:42:18,940 But now it's moving forward. But perhaps at the paces, the terrestrial terrestrial sphere has moved forward in the past. 402 00:42:18,940 --> 00:42:20,230 Right, thanks, yes. 403 00:42:20,230 --> 00:42:25,750 So we've got a question specifically about seagrass, which I'm intrigued by as well, because I've sort of heard about who wants to take that one up. 404 00:42:25,750 --> 00:42:31,420 It's basically how cost effective is seagrass for carbon sequestration for the UK. 405 00:42:31,420 --> 00:42:35,200 And I don't see I'd like to extend it to Charlie Fraser. 406 00:42:35,200 --> 00:42:42,580 Was this and he put cost in brackets. And I'd like to take the cost out there because I'd like seagrass is quite a lot is discussed, 407 00:42:42,580 --> 00:42:49,080 I think, quite a bit around the UK as a carbon sequestration idea. 408 00:42:49,080 --> 00:42:53,660 So what is the potential and could it be cost effective? 409 00:42:53,660 --> 00:42:58,420 Who wants to take that one up? And I'll just say something quickly and I'll open the floor. 410 00:42:58,420 --> 00:43:05,590 But I think from a carbon perspective for Scotland, at least metre squared per year, 411 00:43:05,590 --> 00:43:14,620 seagrass is sequester around 500 grams of carbon dioxide, whereas healthy forestry is around 190 to 700, so it's a big range. 412 00:43:14,620 --> 00:43:20,590 So I actually I would challenge the the the the the notion that they're not as 413 00:43:20,590 --> 00:43:25,520 efficient as forestry because we're talking about efficiency in terms of carbon. 414 00:43:25,520 --> 00:43:32,650 We're not, not kind of just money. And I think potentially you're restoring areas which have been degraded, 415 00:43:32,650 --> 00:43:42,150 so you're not necessarily planting over regions which are being used for the land and uses. 416 00:43:42,150 --> 00:43:45,960 He will say that for the UK, Sophie. 417 00:43:45,960 --> 00:43:52,320 Well, I was I was just going to kind of jump in as well just on the kind of co-benefits side, especially for the economics. 418 00:43:52,320 --> 00:43:58,080 And this is something that affects kind of macro cultivation as an idea as well. 419 00:43:58,080 --> 00:44:05,910 So there's not been a huge number of studies that focus purely on macro with cultivation as a carbon dioxide sequestration technique. 420 00:44:05,910 --> 00:44:12,780 However, there is plenty of evidence that growing microalgae kind of offshore in areas that we currently 421 00:44:12,780 --> 00:44:19,650 don't use for cultivation of crops could be a really efficient way of producing kind of biofuels. 422 00:44:19,650 --> 00:44:24,840 So that would be a great alternative to having to use large swathes of land. 423 00:44:24,840 --> 00:44:35,670 So, yeah, there are potentially some kind of big economic co-benefits to some of these schemes growing biomass just offshore. 424 00:44:35,670 --> 00:44:40,920 And that was. Your muted. 425 00:44:40,920 --> 00:44:47,510 Yeah. You're not anymore. No, no, no. I think Sophia and Roxana have done a good job. 426 00:44:47,510 --> 00:44:50,660 I've got a follow up on seagrass because when you put a forest, 427 00:44:50,660 --> 00:44:58,000 the sort of time scales at which it takes up CO2 is sort of the order of 50 years or so as it's growing. 428 00:44:58,000 --> 00:45:00,170 If you plan a forest on degraded land, 429 00:45:00,170 --> 00:45:08,750 it'll be taking up carbon for a good sort of 50 to 100 years before it reaches full maturity and the rate of carbon uptake slows. 430 00:45:08,750 --> 00:45:11,630 What about seagrass? I mean, what are the timescales here? 431 00:45:11,630 --> 00:45:16,970 If you take an area which used to be sea grass and thought it was seagrass, it might take up a whole lot of carbon. 432 00:45:16,970 --> 00:45:21,980 Right away, but how long does it keep taking carbon up and when does that carbon go? 433 00:45:21,980 --> 00:45:28,670 Yes, that's a good question to seagrass form and these meadows and beds, which have great underlying soils and sediments. 434 00:45:28,670 --> 00:45:34,070 So most of the storage and seagrass is not actually associated with the living green stuff that you see, 435 00:45:34,070 --> 00:45:40,700 but more so in the underlying soils and sediments. And that would be wrong that considered long term carbon sequestration. 436 00:45:40,700 --> 00:45:44,900 So for long timescales, hundreds of years, so they are comparable stores, 437 00:45:44,900 --> 00:45:52,280 whereas something like kelp help only stores carbon in the living kelp seaweed biomass. 438 00:45:52,280 --> 00:45:57,890 So you actually need to get that kelp into long term carbon sediment stores, for instance, on the seafloor sediments. 439 00:45:57,890 --> 00:46:03,470 In order for it to be kind of considered to be locking down that carbon, that's why when it comes to the aquaculture stuff, 440 00:46:03,470 --> 00:46:07,460 you either need to harvest it and then take all out the sea or do something else with it, 441 00:46:07,460 --> 00:46:12,000 rather than just letting it rot and then releasing that carbon back up to the user. 442 00:46:12,000 --> 00:46:18,050 Yes, the issue of Times Square is something important to consider. 443 00:46:18,050 --> 00:46:22,310 We got several questions about timescales that we've already been touching on, 444 00:46:22,310 --> 00:46:27,980 but there's one really interesting question from Felicia Lou on governance mechanisms. 445 00:46:27,980 --> 00:46:35,570 I mean, this is obviously a big priority for Oxford. Net zero is how do we how do we manage all this, all these different policies and technologies? 446 00:46:35,570 --> 00:46:38,600 I mean, I don't know who wants, you know, 447 00:46:38,600 --> 00:46:47,720 obviously Law of the Sea as a big governance criterion or sort of framework in which all of these discussions are taking place. 448 00:46:47,720 --> 00:46:53,210 But does anybody want to talk to the the way in which we're setting about or we could set 449 00:46:53,210 --> 00:47:01,100 about governing large scale implementation of some of these carbon storage solutions? 450 00:47:01,100 --> 00:47:09,830 He wants to take that one up. I'm happy to jump in quickly, but I think Roxana is definitely the expert on blue carbon here, 451 00:47:09,830 --> 00:47:14,240 but just specifically in terms of some of the other techniques. 452 00:47:14,240 --> 00:47:20,570 I think there's a real difference that comes up between whether schemes are considered kind of coastal, 453 00:47:20,570 --> 00:47:24,860 whether they can be considered into the kind of national jurisdiction of a particular country, 454 00:47:24,860 --> 00:47:27,740 for example, or whether they are an international scheme. 455 00:47:27,740 --> 00:47:37,070 So just speaking to iron fertilisation, which is one of probably the major most researched schemes out of the kind of artificial manipulation side, 456 00:47:37,070 --> 00:47:39,830 one of the major things that kept coming up was, well, 457 00:47:39,830 --> 00:47:47,450 there isn't currently any piece of legislation that would properly account for the governance of such a scheme where 458 00:47:47,450 --> 00:47:54,470 it kind of large scale intervention in the ocean and depending on why you do it completely international waters. 459 00:47:54,470 --> 00:48:04,130 So I think for these kind of offshore international schemes, we will probably need to see some specific legislation drawn up. 460 00:48:04,130 --> 00:48:10,700 For example, I think it's the London protocol. It just doesn't cover the right, the right basis. 461 00:48:10,700 --> 00:48:18,830 So yeah, we need we need. We need lawyers working on this. But yes, for kind of more coastal schemes like, for example, 462 00:48:18,830 --> 00:48:25,370 mackerel cultivate Asian blue carbon management, that side of things, it does become a lot easier. 463 00:48:25,370 --> 00:48:32,630 So yeah, depending on whether it's kind of international or national. Roxana, did you want to entertain? 464 00:48:32,630 --> 00:48:35,960 Yes, I kind of a regional like national level, 465 00:48:35,960 --> 00:48:42,530 the and there are opportunities for protecting and using blue carbon ecosystems for climate change mitigation. 466 00:48:42,530 --> 00:48:47,210 And it's, as I mentioned, it's moving at a much slower pace in this restaurant environment. 467 00:48:47,210 --> 00:48:56,510 The impression I get is that this the big geoengineering strategies will require a coordinated strategic framework internationally, 468 00:48:56,510 --> 00:49:04,400 whereas there are ready opportunities for countries to be using blue carbon, blue carbon and policy to make those changes. 469 00:49:04,400 --> 00:49:09,860 Now, whereas the I don't know, Sophie, correct me if I'm wrong, 470 00:49:09,860 --> 00:49:18,590 that the big kind of do engineering techniques are perhaps not there yet in terms of the framework that is needed in order to to move it, 471 00:49:18,590 --> 00:49:23,940 to move forward at pace. And. 472 00:49:23,940 --> 00:49:33,880 To Georgia Tech, yeah. No, but it's just as a final point, I guess not all ocean chemistry manipulation has to occur out at sea. 473 00:49:33,880 --> 00:49:38,020 I guess again, we sort of go back to my comfort zone of ocean alkalinity enhancement, 474 00:49:38,020 --> 00:49:48,120 but there are certainly ideas and projects that are about to be deployed at a field scale that use the process of accelerated weathering, 475 00:49:48,120 --> 00:49:55,390 of spreading rocks onto to crops to accelerate the weathering components of carbon drawdown. 476 00:49:55,390 --> 00:50:01,700 And that would lead, we think, to alkalinity runoff into two streams and rivers and then ultimately into the sea. 477 00:50:01,700 --> 00:50:06,580 So I guess just I mean, it's I think in a way, 478 00:50:06,580 --> 00:50:10,390 we've got three scientists here you can who can speak best to the science of these 479 00:50:10,390 --> 00:50:14,710 these processes more perhaps than the intricacies of the policies and the economies. 480 00:50:14,710 --> 00:50:23,620 But it is an incredibly interconnected problem in the sense that some of these deployment schemes can occur on land, I guess, is my point. 481 00:50:23,620 --> 00:50:34,990 And then the question is how long governs? No, I don't think at the moment the the the the law controls how much alkalinity comes out of rivers. 482 00:50:34,990 --> 00:50:40,360 I don't think that's something that's currently legislated against or before. 483 00:50:40,360 --> 00:50:44,230 Yeah, of course, all these corrections are exactly why we need Oxford zero. 484 00:50:44,230 --> 00:50:54,550 So shameless plug. But so can I just ask a specific question, which we just been asked about some CFC 11 and that sink reversal. 485 00:50:54,550 --> 00:50:58,720 But rather than just focussing on just specifically that? 486 00:50:58,720 --> 00:51:08,410 Can I broaden that a bit to? Well, one of the big concerns we've got with nature based solutions on land is the possibility that as the world warms, 487 00:51:08,410 --> 00:51:13,030 some of the carbon stores that were just as a result of global warming itself, 488 00:51:13,030 --> 00:51:19,540 some of the carbon stores that we're relying on to mop up fossil carbon emissions may become 489 00:51:19,540 --> 00:51:23,980 less reliable or even reverse and start rereleasing that carbon back into the atmosphere. 490 00:51:23,980 --> 00:51:29,750 So I mean, is that something which we worry we should be worrying about in terms of ocean carbon storage as well? 491 00:51:29,750 --> 00:51:41,530 That the success of ocean carbon storage almost depends on our success in actually stopping global warming in the first place? 492 00:51:41,530 --> 00:51:47,020 So I can speak a little bit if if you want, yes, there. 493 00:51:47,020 --> 00:52:00,380 I think that's that's very true, and there is an element by which let's say we were to to accelerate terrestrial based systems for sequester. 494 00:52:00,380 --> 00:52:07,640 Strings, the carbon that it has been storing well, we've been going through this anthropogenic perturbation, but that's it. 495 00:52:07,640 --> 00:52:10,070 That's the sort of mass balance problem, I guess. 496 00:52:10,070 --> 00:52:19,280 I guess what I what I wanted to say is that certainly it would seem if I if I take my geologists household and and look at the glacial termination, 497 00:52:19,280 --> 00:52:24,410 then as that started to be released, it was clear they were positive feedbacks in the system, 498 00:52:24,410 --> 00:52:28,400 which allowed the CO2 to keep on going up in the atmosphere. 499 00:52:28,400 --> 00:52:33,800 And, you know, just just taking that very simply thinking about, say, stratification in the ocean. 500 00:52:33,800 --> 00:52:37,730 For example, as you as you warm the ocean, 501 00:52:37,730 --> 00:52:47,720 you'll get a change of density contrasts across the ocean and potentially help the mixing and the rerelease of CO2, potentially from the deep waters. 502 00:52:47,720 --> 00:52:53,030 We would have exactly the same impacts we certainly thought about and the impacts of 503 00:52:53,030 --> 00:52:58,370 temperature on re mineralisation of organic carbon rates and as you increase temperature. 504 00:52:58,370 --> 00:53:05,120 So make sure that all the organic carbon you make in the in the biological pump will release much faster and therefore shallower, 505 00:53:05,120 --> 00:53:08,600 and therefore have more potential to go back up into the atmosphere. 506 00:53:08,600 --> 00:53:18,230 So I think, yes, there are a very clear temperature impacts on carbon feedbacks within the ocean. 507 00:53:18,230 --> 00:53:23,300 I guess again, you know, safe you. I probably always go back to work Lindsay enhancement. 508 00:53:23,300 --> 00:53:27,890 But that's one that I think is less sensitive to CO2 naturally raising the age. 509 00:53:27,890 --> 00:53:34,320 It's it's kind of that is manipulating the chemistry back to where it should be. 510 00:53:34,320 --> 00:53:39,180 Yeah, I think the same applies for blue carbon environment. I mean, the kind of biological species as well. 511 00:53:39,180 --> 00:53:46,260 There's already evidence that the phytoplankton, which are these main kind of sequesters of carbon dioxide around the coast, 512 00:53:46,260 --> 00:53:54,720 that this species distribution has changed over the last in response to warming and different species sequester carbon at a different rate. 513 00:53:54,720 --> 00:54:01,170 So there will be effects. I don't think this is a problem that's necessarily unique to terrestrial environments, 514 00:54:01,170 --> 00:54:07,760 but definitely one that needs to be considered in the oceans as well. 515 00:54:07,760 --> 00:54:18,650 Thanks. Did you want to specify what? Great, so, so so there's a more general, by the way, I've learnt what's microalgae are seaweed for me. 516 00:54:18,650 --> 00:54:24,170 I can't I learn something every week, but that's the great thing about these seminars. 517 00:54:24,170 --> 00:54:31,040 But there's a more just that sort of wrap up on a much more general question from Martin Gibson. 518 00:54:31,040 --> 00:54:35,900 Pollution control has been moving away from end of pipe solutions. And in a sense, 519 00:54:35,900 --> 00:54:39,470 what we're talking about here is beyond the end of the pipe in the sense that it's 520 00:54:39,470 --> 00:54:43,760 sort of dealing with the carbon dioxide after it's been released into the atmosphere. 521 00:54:43,760 --> 00:54:50,630 And the question is, are we suggesting reversing this and promoting the ocean as the solution to high carbon emissions? 522 00:54:50,630 --> 00:54:56,390 And if I might, so just please pass this over to two or three speakers as well. 523 00:54:56,390 --> 00:55:06,200 But just to stress that the emphasis of Oxford net zero almost inevitably is on thinking beyond the kind of, 524 00:55:06,200 --> 00:55:12,740 you know, the ocean alternate, your initiative is about the sort of final twenty five percent of emissions. 525 00:55:12,740 --> 00:55:20,720 It's about the hard to abate sectors, the economic activities that are so valuable that it's very hard to imagine 526 00:55:20,720 --> 00:55:24,590 any conceivable carbon progress discouraging people from doing them at all. 527 00:55:24,590 --> 00:55:32,210 So in a sense, just by the question, by the exam question we've set ourselves in in the Oxford That Zero initiative, 528 00:55:32,210 --> 00:55:41,300 we are thinking more in terms of what people consider end of pipe solutions. 529 00:55:41,300 --> 00:55:48,710 Of course, that doesn't take away from the importance of reducing emissions in the short term and curtailing the total amount of carbon we 530 00:55:48,710 --> 00:55:55,070 have to deal with in the first place because there's obvious limits as we've heard more speakers on these and the pipe solutions. 531 00:55:55,070 --> 00:55:58,940 But you know, that's that's the easiest question we set ourselves in. 532 00:55:58,940 --> 00:56:08,000 In a sense, we need to know how these things could work just in case we need them, even if we hope that we never will. 533 00:56:08,000 --> 00:56:15,350 Certainly for some of the more sort of extreme scenarios of having to mop up very large volumes of carbon, 534 00:56:15,350 --> 00:56:17,990 but just actually over to Sophie Sophie on this, 535 00:56:17,990 --> 00:56:26,900 because you've been sort of thinking in the in the big picture on this sort of picture of how do you when you're talking to people about this, 536 00:56:26,900 --> 00:56:33,110 how do you balance out these interventions with the challenge of reducing emissions in the first place? 537 00:56:33,110 --> 00:56:39,410 Sort of at what point if if a tech company comes to you and says, Look, we want to get to net zero tomorrow, 538 00:56:39,410 --> 00:56:43,640 but we've heard we're going to do what you can do this with just some blue carbon solutions. 539 00:56:43,640 --> 00:56:49,700 You know, what's the answer? Good question. To be honest, I don't think there is a simple answer to this at all. 540 00:56:49,700 --> 00:56:55,790 And one of the major problems I found with both kind of looking at this on a bigger picture scale 541 00:56:55,790 --> 00:57:01,790 and a more kind of consulting capacity and also working on this specifically as a Ph.D. student, 542 00:57:01,790 --> 00:57:07,640 one of these schemes in particular, I think one of the major challenges is this kind of moral hazard that I think has been 543 00:57:07,640 --> 00:57:12,350 brought up at multiple times in these these talks and they are supporting schools, 544 00:57:12,350 --> 00:57:17,270 being having kind of a you kicking the can down the road, 545 00:57:17,270 --> 00:57:21,620 telling people that they don't have to reduce their emissions because at some point along the line, 546 00:57:21,620 --> 00:57:26,930 there's going to be a technological innovation that's going to save the world and we're not going to have to worry about CO2 emissions. 547 00:57:26,930 --> 00:57:31,820 We just will have something that cleans up a bit like you have your rubbish taken out every day, 548 00:57:31,820 --> 00:57:37,610 which I think is unrealistic to assume that we will be able to offset all of our emissions using schemes like this. 549 00:57:37,610 --> 00:57:44,570 However, my personal kind of opinion on this is that it's very clear that we need to 550 00:57:44,570 --> 00:57:49,010 actively remove carbon from the atmosphere as well as reduce our emissions. 551 00:57:49,010 --> 00:57:49,550 Otherwise, 552 00:57:49,550 --> 00:57:58,910 we are not going to meet the kind of 1.5 degree or two degree target that we really need to hit to avoid some of the worst impacts on ecosystems, 553 00:57:58,910 --> 00:58:02,990 biodiversity and human life as well. 554 00:58:02,990 --> 00:58:07,220 So I think ideally, we wouldn't be in a situation where we need these schemes. 555 00:58:07,220 --> 00:58:18,890 However, we are. So we need we need to do the research now to make sure that we are able to implement these in a safe way if we do require them. 556 00:58:18,890 --> 00:58:21,590 But yeah, in an ideal world, like I said, we would not need these, 557 00:58:21,590 --> 00:58:28,790 but I think it is becoming apparent that we will need things to actively remove carbon as well as reducing emissions. 558 00:58:28,790 --> 00:58:31,400 Well, thank you. Thank you. That's couldn't really. 559 00:58:31,400 --> 00:58:39,320 I couldn't really top that as a way of ending these, this series of seminars from the Oxford Net Zero initiative. 560 00:58:39,320 --> 00:58:46,670 So since we're on the hour, it remains just me to thank all three speakers today very much for some, 561 00:58:46,670 --> 00:58:52,550 some really great presentations and also particularly to thank the Oxford Martin School and 562 00:58:52,550 --> 00:59:00,620 Clara Barria for hosting all of these behind the scenes making this series of events possible. 563 00:59:00,620 --> 00:59:06,320 Don't forget, we have the formal launch of the oxybenzone initiative in a month or so's time, 564 00:59:06,320 --> 00:59:11,020 the 7th of May that afternoon, and you can hear from a number of. 565 00:59:11,020 --> 00:59:15,760 Both academics associated with initiatives and politicians and business people who are working with us, 566 00:59:15,760 --> 00:59:20,620 as well as the Mongkok down in your diary and all of these folks have been recorded, 567 00:59:20,620 --> 00:59:27,340 so you can find them all on the Oxford Martin School website and to get in touch with the Oxford Net Zero initiative. 568 00:59:27,340 --> 00:59:33,040 If you want to stay on our mailing list and keep abreast of what we're doing because the initiatives that are just starting, 569 00:59:33,040 --> 00:59:42,400 we've had a lot to do in the next few years. Thank you all very much for joining these seven of both the participants, the questioners, the speakers. 570 00:59:42,400 --> 00:59:47,650 It's been a great series. We've had a fantastic turnout of people. 571 00:59:47,650 --> 00:59:55,130 We've made the most of being online and will, but we are nevertheless as as the as the world turns, 572 00:59:55,130 --> 01:00:00,160 we are hoping we'll be seeing some of you in person before too long. So thank you all very much. 573 01:00:00,160 --> 01:00:05,083 Thanks to you and Clara for hosting everything thanks to our speakers today and have a good afternoon.