WEBVTT 00:05.560 --> 00:08.600 WATER GURGLES 00:08.600 --> 00:10.900 For over 12,000 years, 00:10.900 --> 00:14.500 we and millions of other species on the planet have benefited 00:14.500 --> 00:18.000 from an atmosphere which has given us a stable climate 00:18.000 --> 00:20.000 and life-giving air. 00:20.000 --> 00:23.080 But how often do we stop to think about our atmosphere and the air 00:23.080 --> 00:24.920 that we breathe? 00:52.120 --> 00:55.360 APPLAUSE 01:03.000 --> 01:06.640 Hi, I'm Dr Tara Shine and I'm an environmental scientist. 01:06.640 --> 01:10.600 Welcome to the last of this year's Christmas lectures. 01:10.600 --> 01:12.840 We started by looking at the Earth with Chris 01:12.840 --> 01:15.600 and then we explored the oceans with Helen. 01:15.600 --> 01:19.680 And today, we're going to look at our own atmosphere, how it works, 01:19.680 --> 01:23.200 the effect we're having on it, and what we can do to protect it. 01:23.200 --> 01:26.920 This is Andy. Andy is Alice Hickson's safety diver. 01:26.920 --> 01:30.800 And as you can see, Alice is submerged under the water 01:30.800 --> 01:32.840 and she's holding her breath. 01:32.840 --> 01:36.400 Alice has trained to do this for many years as a freediver, 01:36.400 --> 01:38.880 so please do not try this at home. 01:38.880 --> 01:41.320 As you can see, Alice has already been underwater 01:41.320 --> 01:44.120 for more than a minute and a half, holding her breath. 01:44.120 --> 01:46.320 I wish I could do what Alice is doing. 01:46.320 --> 01:49.640 I love the sea, I love swimming, and I get really frustrated 01:49.640 --> 01:53.560 when I'm not able to hold my breath long enough to chase that crab 01:53.560 --> 01:57.360 or that fish, and I'm forced back to the surface by the need to breathe. 01:57.360 --> 01:59.720 That's why I learned to scuba dive. 01:59.720 --> 02:03.080 When I scuba dive, I use a tank like this one. 02:03.080 --> 02:05.920 Now, lots of people think this tank is filled with oxygen. 02:05.920 --> 02:09.960 They might even call it an oxygen tank, but pure oxygen at depth 02:09.960 --> 02:12.200 would be toxic to my body. 02:12.200 --> 02:15.680 Instead, this tank is filled with compressed air. 02:15.680 --> 02:18.680 But what is in the air that we breathe? 02:18.680 --> 02:22.400 Perhaps because we can't see it that's why we take it for granted. 02:22.400 --> 02:24.560 AIR HISSES 02:24.560 --> 02:27.200 But what if I cooled this air down? 02:27.200 --> 02:31.000 And by that I mean, what if I cooled it down A LOT 02:31.000 --> 02:35.040 to minus 200 degrees Celsius? 02:36.320 --> 02:38.120 At that temperature, 02:38.120 --> 02:43.240 the gas becomes liquid and we can see it. 02:43.240 --> 02:46.520 So what I'm going to do is pour this into this container. 02:46.520 --> 02:50.240 As you can see, it's a clear liquid. This is nitrogen, 02:50.240 --> 02:55.720 liquid nitrogen, and nitrogen makes up 78% of our atmosphere. 02:57.240 --> 02:59.120 I'm filling that almost up to the top, 02:59.120 --> 03:00.880 it's bubbling all over the place. 03:02.400 --> 03:05.640 So there's not just nitrogen in the atmosphere. 03:05.640 --> 03:07.240 What might be in this red flask? 03:07.240 --> 03:10.200 Let's pour that out. It's a beautiful blue colour. 03:10.200 --> 03:13.520 This is oxygen, liquid oxygen, that life-giving gas. 03:13.520 --> 03:17.240 21% of our atmosphere is made up of oxygen. 03:18.760 --> 03:22.880 So that leaves 1%, and 1% is made up of trace gases 03:22.880 --> 03:24.800 like argon, methane. 03:24.800 --> 03:28.040 And this here, 0.04% of our atmosphere 03:28.040 --> 03:30.720 is made up of carbon dioxide. 03:30.720 --> 03:34.760 And it is this same gas, carbon dioxide, that's building up 03:34.760 --> 03:38.800 in Alice's body right now and making her want to breathe. 03:38.800 --> 03:40.560 So let's go check on Alice. 03:40.560 --> 03:44.400 Wow, look, Alice has already been underwater 03:44.400 --> 03:47.160 for three minutes, 50 seconds. 03:47.160 --> 03:50.440 As I've told you, she is trained to do this. 03:50.440 --> 03:54.120 Alice is the UK World Champion Women Freediver. 03:54.120 --> 03:58.600 But let's get her up now to talk to her about what she's doing 03:58.600 --> 04:01.360 and how she does it. Andy, can you give her a tap for me? 04:01.360 --> 04:04.280 So she's at four minutes and ten seconds. 04:04.280 --> 04:06.080 Amazing. 04:06.080 --> 04:09.480 Alice! Four minutes and ten seconds. I don't know how you do it. 04:09.480 --> 04:11.600 I wish I could do it! 04:11.600 --> 04:13.800 That's incredible. How do you feel? 04:13.800 --> 04:16.800 I'm all right. You're all right. You're just, no bother. 04:16.800 --> 04:18.320 Tell me, how do you do it? 04:18.320 --> 04:21.520 How do you, how do you resist the urge to breathe? Stubbornness? 04:21.520 --> 04:26.080 Stubbornness. And lots of practice, and training your body to get used 04:26.080 --> 04:29.160 to the tolerance of the build-up of carbon, carbon dioxide 04:29.160 --> 04:31.800 and lactic acid and, yeah, just lots of practice. 04:31.800 --> 04:34.000 Do you also need to be very relaxed? 04:34.000 --> 04:38.000 Yeah, it's as much a psychological thing as it is a physical thing. 04:38.000 --> 04:39.880 What kind of records do you hold? 04:39.880 --> 04:43.120 All the British pool records and then the depth records. 04:43.120 --> 04:48.440 So, for no fins, which is swimming as deep as you can without fins, 04:48.440 --> 04:52.640 a bit like breaststroke, so I can swim 60 metres deep under the water 04:52.640 --> 04:56.720 and back without fins, and then I can hold my breath 04:56.720 --> 04:59.440 for 6.58 is the official record. Wow. Yeah. 04:59.440 --> 05:01.680 And you didn't do a whole lot of like, kind of... 05:01.680 --> 05:04.080 SHE GASPS ..stuff before you went down. 05:04.080 --> 05:06.680 Hyperventilating makes it dangerous. That's not a good thing. 05:06.680 --> 05:09.680 It's more about being relaxed. Thank you, Alice. That was just amazing. 05:09.680 --> 05:11.840 I can't believe you stayed under for four minutes. 05:11.840 --> 05:13.600 Thank you. Thank you. 05:13.600 --> 05:17.840 Carbon dioxide is a waste product from the production of energy 05:17.840 --> 05:20.040 in our bodies and from respiration. 05:20.040 --> 05:23.520 So, we breathe in oxygen and we use that along with glucose 05:23.520 --> 05:26.280 from our food to produce energy. 05:26.280 --> 05:28.760 And the waste products from that process 05:28.760 --> 05:31.200 are water and carbon dioxide. 05:31.200 --> 05:33.480 APPLAUSE 05:41.880 --> 05:44.360 Hello and welcome to our virtual audience. 05:44.360 --> 05:46.680 Lovely to see you. 05:46.680 --> 05:50.720 So, if I use a camera like this special camera here, I can actually 05:50.720 --> 05:53.760 see the CO2 being breathed out by Malcolm. 05:53.760 --> 05:55.800 So, if you have a look here on the monitor, 05:55.800 --> 05:58.760 you can see the CO2 being breathed out. 05:58.760 --> 06:01.800 And, luckily, what is a waste gas to us 06:01.800 --> 06:04.800 is fuel for plants in photosynthesis, 06:04.800 --> 06:08.760 where they use this carbon dioxide to create oxygen. 06:10.080 --> 06:11.880 So, thank you, Malcolm. 06:11.880 --> 06:15.240 But how could something as natural as carbon dioxide, something 06:15.240 --> 06:18.760 we breathe out, be bad for us and cause pollution? 06:20.000 --> 06:24.320 Well, when we burn ancient carbon stored as fossil fuels, 06:24.320 --> 06:26.680 we emit carbon dioxide. 06:26.680 --> 06:30.000 Now, fossil fuels were formed millions of years ago. 06:30.000 --> 06:34.600 They were formed when plants and other organisms were laid down 06:34.600 --> 06:37.920 in decomposing layers under sediment and rock. 06:37.920 --> 06:43.200 And when we burn that fossil carbon, it emits much greater amounts 06:43.200 --> 06:46.600 of carbon dioxide than Malcolm did when he was just breathing. 06:46.600 --> 06:50.640 So, what we're going to do here is a little experiment, very exciting. 06:50.640 --> 06:54.920 So, I am going to... We are going to, together, Fran and I, 06:54.920 --> 06:58.920 we're going to set some coal dust, some fossil fuel alight, 06:58.920 --> 07:02.320 and we're going to see what kind of energy we can get from that 07:02.320 --> 07:05.240 and how much CO2 can we produce from that. 07:06.440 --> 07:08.760 So, audience, we're going to need a countdown for this. 07:08.760 --> 07:10.760 With me, five... 07:10.760 --> 07:13.480 ALL: ..four, three, two, one. 07:14.720 --> 07:17.440 Whoo! Look at that. 07:17.440 --> 07:21.400 Imagine, if we can get all of that energy and that huge amount 07:21.400 --> 07:25.560 of carbon dioxide from just a few little grams of coal dust, 07:25.560 --> 07:30.240 imagine that on the scale of a power station or on the scale of thousands 07:30.240 --> 07:31.960 of power stations. 07:31.960 --> 07:36.080 That is the energy we have been using to develop our countries 07:36.080 --> 07:40.200 to industrialise for over 200 years since the Industrial Revolution. 07:40.200 --> 07:43.560 And the result of that is that we have put an awful lot 07:43.560 --> 07:47.120 of carbon dioxide up into our atmosphere, enough carbon dioxide 07:47.120 --> 07:48.920 to profoundly change it. 07:48.920 --> 07:52.960 So, if we look up here at our globe, we can see these concentrations 07:52.960 --> 07:55.880 of carbon dioxide swirling around our planet. 07:55.880 --> 07:59.440 All that yellow and red is showing us these higher concentrations 07:59.440 --> 08:01.760 of carbon dioxide in our atmosphere. 08:01.760 --> 08:06.320 So, back in 1850, there was 286 parts per million 08:06.320 --> 08:09.120 of carbon dioxide in our atmosphere. 08:09.120 --> 08:15.200 And now, today, we have increased that to 415 parts per million. 08:15.200 --> 08:18.200 So, carbon dioxide, one of the greenhouse gases, 08:18.200 --> 08:21.280 along with other greenhouse gases like methane, 08:21.280 --> 08:24.040 is causing our planet to warm. 08:24.040 --> 08:26.680 And we have already warmed our planet by between 08:26.680 --> 08:31.200 1.1 and 1.2 degrees of warming. 08:31.200 --> 08:34.920 So, our planet is now a degree warmer than it was when we started 08:34.920 --> 08:36.880 the Industrial Revolution. 08:36.880 --> 08:40.480 So, one degree of warming might not sound like a lot. 08:40.480 --> 08:42.600 Is it really a big deal? 08:42.600 --> 08:45.840 Well, let's think about it in terms of our own bodies, OK? 08:45.840 --> 08:48.320 So, you're all getting your temperature taken all the time 08:48.320 --> 08:49.880 at the moment, yeah? 08:49.880 --> 08:52.720 To get into the dentist, sometimes into a shop or a restaurant, 08:52.720 --> 08:54.880 you might have to have your temperature taken. 08:54.880 --> 08:57.680 So, our average temperature as human beings, 08:57.680 --> 09:03.520 what it should be is between 36 and 36.8 degrees. 09:03.520 --> 09:06.760 So this is what our normal temperature should be. 09:06.760 --> 09:10.960 And if that increases by one degree, because we've been talking about one 09:10.960 --> 09:14.640 degree, to 37 to 37.8 degrees, 09:14.640 --> 09:16.920 well, we're still OK. 09:16.920 --> 09:20.640 We might feel a little bit hot, a bit flushed, but we're not unwell. 09:20.640 --> 09:24.320 But if we look at the upper end of this temperature here 09:24.320 --> 09:27.920 and we increase our temperature by just 0.2 degrees Celsius more, 09:27.920 --> 09:30.520 up to 38 degrees, 09:30.520 --> 09:34.880 we're now suddenly in the threshold of being unwell. 09:34.880 --> 09:36.960 We'll have a temperature. 09:36.960 --> 09:39.320 We might even have a fever. 09:39.320 --> 09:44.120 And so, every degree and every part of a degree of warming matters 09:44.120 --> 09:49.120 to our health, but it also matters to the health of our planet. 09:49.120 --> 09:52.720 What's also important when we think about how the Earth is warming 09:52.720 --> 09:57.760 and how unwell it may be getting is that, that heat rise, 09:57.760 --> 10:01.200 that increase in temperature, is not evenly spread across the globe. 10:01.200 --> 10:05.040 So how you feel this warming depends on where you live. 10:05.040 --> 10:09.400 So if we look up here at our chart, we'll see that the warming is most 10:09.400 --> 10:11.200 intense in the Arctic. 10:11.200 --> 10:14.080 We can see areas of warming over our oceans 10:14.080 --> 10:16.600 as the oceans absorb the extra heat, 10:16.600 --> 10:19.200 and we can see warming over the continents, 10:19.200 --> 10:21.200 over the big land masses. 10:22.200 --> 10:24.400 And if we go over here to our globe, 10:24.400 --> 10:28.200 another continent that's warming a lot is Africa. 10:28.200 --> 10:31.520 And here over the Sahel and the Sahara Desert, 10:31.520 --> 10:35.920 places that are already really hot, it's getting even hotter. 10:35.920 --> 10:40.400 And in a country here called Chad, temperatures are rising faster 10:40.400 --> 10:44.120 than the global average, and rainfall is decreasing. 10:44.120 --> 10:46.240 But don't take my word for it. 10:46.240 --> 10:48.800 Please come over with me now and we're going to talk to 10:48.800 --> 10:52.560 Hindou Oumarou Ibrahim, who is an indigenous woman from Chad. 10:52.560 --> 10:55.440 Hello, Hindou. Good to see you. 10:55.440 --> 10:58.520 Hi, Tara, good to see you, too. How are you keeping? 10:58.520 --> 11:01.440 Oh... I don't want to ask you that. Hot. Hot! 11:01.440 --> 11:06.920 So, Hindou, can you tell me how the climate is already changing in Chad? 11:06.920 --> 11:10.640 We already have plus 1.5 degree. 11:10.640 --> 11:15.280 And that mean for us, the Lake Chad, who is the bigger lake, 11:15.280 --> 11:20.360 who used to be in 1960, 25,000km squares, 11:20.360 --> 11:23.440 shrink to 90%. 11:23.440 --> 11:26.720 And imagine, communities are fighting to get access 11:26.720 --> 11:28.640 to the shrinking resources. 11:28.640 --> 11:32.440 They are leaving this place to become refugees. 11:32.440 --> 11:35.840 So climate change is impacting the food security. 11:35.840 --> 11:40.400 It's impacting the lives and livelihoods of the communities, 11:40.400 --> 11:43.720 and it's creating the conflict among all the rest 11:43.720 --> 11:45.200 of the population. 11:45.200 --> 11:49.160 And, Hindou, tell me how you're using the 3D mapping to create 11:49.160 --> 11:52.800 this picture of how climate change is affecting your community. 11:52.800 --> 11:57.800 Tara, this is the fantastic exercise of how we can use the science 11:57.800 --> 12:00.840 knowledge and traditional knowledge together. 12:00.840 --> 12:05.120 So 3D participatory mapping, it's gathering all the communities, 12:05.120 --> 12:08.240 those who didn't have the chance to go to school 12:08.240 --> 12:11.800 but who know better the environment, they come, 12:11.800 --> 12:15.080 they put all the traditional knowledge in a scientific 12:15.080 --> 12:19.960 geographical map, and that can help to better see the areas 12:19.960 --> 12:22.400 who are the most vulnerable. 12:22.400 --> 12:26.240 The 3D mapping, it's a great exercise that can help 12:26.240 --> 12:30.080 the government to look at the communities and consider 12:30.080 --> 12:33.040 what they need to change the policies. 12:33.040 --> 12:36.600 And when we talk about climate change at the international level, 12:36.600 --> 12:41.360 so they need a local knowledge and those local knowledge can be easily 12:41.360 --> 12:45.040 understood through the 3D participatory mapping. 12:45.040 --> 12:48.400 Thank you, Hindou, that's fascinating about how we can 12:48.400 --> 12:51.520 blend traditional scientific monitoring and modelling 12:51.520 --> 12:53.840 with the indigenous knowledge that you're collecting 12:53.840 --> 12:55.440 in your community. 12:55.440 --> 12:58.920 So, Hindou, before you go, can you just tell me, 12:58.920 --> 13:01.640 does Chad produce a lot of greenhouse gas emissions? 13:01.640 --> 13:05.760 Tara, no. In my community, there are no car. 13:05.760 --> 13:07.280 We do not have big buildings. 13:07.280 --> 13:10.400 We don't have aeroplanes for ourselves. 13:10.400 --> 13:13.320 Even peoples do not have access to the electricity. 13:13.320 --> 13:16.640 So, one person in Chad produce 13:16.640 --> 13:21.160 0.06 of a metric of tonne. 13:21.160 --> 13:24.880 So we are not responsible at all of climate change, 13:24.880 --> 13:27.040 but we are the most impacted. 13:27.040 --> 13:29.000 Thank you very much, Hindou. 13:29.000 --> 13:31.760 APPLAUSE 13:35.240 --> 13:38.120 So as we can see, a person in Chad 13:38.120 --> 13:42.240 produces less than 0.1 of a tonne 13:42.240 --> 13:44.920 of carbon dioxide a year. 13:44.920 --> 13:49.200 So, each one of these black balls represents 0.1 of a tonne 13:49.200 --> 13:52.360 of carbon dioxide, what comes from one person in Chad. 13:52.360 --> 13:55.600 So let's compare this to some other countries in the world. 13:55.600 --> 13:58.120 OK, first of all, we're going to go to India. 13:58.120 --> 14:02.720 So, India is a developing country, it's industrialising fast, 14:02.720 --> 14:07.040 it has a very large population and each person in India produces 14:07.040 --> 14:11.840 1.9 tonnes of carbon dioxide a year. 14:11.840 --> 14:15.080 So more than Chad, 19 times more than Chad, 14:15.080 --> 14:17.360 but still very modest. 14:18.760 --> 14:21.680 What about if we look at ourselves at home in the United Kingdom? 14:21.680 --> 14:24.840 Each person in the United Kingdom 14:24.840 --> 14:30.760 produces 5.5 tonnes of carbon dioxide a year. 14:30.760 --> 14:34.640 So that's 55 times more than someone in Chad. 14:34.640 --> 14:38.280 So if we go over to the United States of America, 14:38.280 --> 14:41.880 each person there is responsible for producing 14:41.880 --> 14:47.080 15.5 tonnes of CO2 every year, 14:47.080 --> 14:50.360 released right up into our atmosphere. 14:50.360 --> 14:53.640 So, as you can see, that is so much more than one person 14:53.640 --> 14:55.920 in Hindou's community in Chad. 14:55.920 --> 14:57.920 And that's the thing about climate change, 14:57.920 --> 15:00.120 climate change is very unfair. 15:00.120 --> 15:03.760 It's unfair in terms of who's responsible for causing the problem 15:03.760 --> 15:05.880 but, as we learned from Hindou, 15:05.880 --> 15:08.720 it's also unfair in terms of the impacts. 15:08.720 --> 15:11.880 So the people who are suffering the most from climate change 15:11.880 --> 15:13.880 are the people who are least responsible. 15:13.880 --> 15:17.440 This is called climate injustice. 15:17.440 --> 15:19.960 And if we look around the world, we can see that people 15:19.960 --> 15:22.200 are being impacted right around the planet 15:22.200 --> 15:25.000 in many different ways by climate change. 15:25.000 --> 15:26.800 On the globe at the moment, 15:26.800 --> 15:30.680 you can see wildfires spread right across the world. 15:30.680 --> 15:34.280 And while wildfires are a natural phenomenon, they're becoming 15:34.280 --> 15:37.560 more frequent and more intense now due to climate change. 15:37.560 --> 15:41.720 And look, if we look at Australia, Australia last summer experienced 15:41.720 --> 15:44.640 one of their most ferocious wildfire seasons. 15:44.640 --> 15:47.920 And in fact, research has shown that the weather that led 15:47.920 --> 15:50.600 to those wildfires was 30% more likely 15:50.600 --> 15:53.280 because of human-induced climate change. 15:53.280 --> 15:56.440 And in Europe, we're experiencing this changing weather in terms of 15:56.440 --> 15:58.680 gradual changes to our seasons. 15:58.680 --> 16:02.360 Our winters are getting warmer and wetter, but also in terms of 16:02.360 --> 16:06.000 more extremes like storms, floods and heatwaves. 16:06.000 --> 16:10.000 So, as we've seen from Hindou, climate change is already having 16:10.000 --> 16:13.560 a very real impact on the life of people around the world. 16:13.560 --> 16:17.600 So, let's play a game to see if we can better understand 16:17.600 --> 16:20.720 the impacts that global warming is going to have on our ability 16:20.720 --> 16:23.960 to feed an ever-growing global population. 16:23.960 --> 16:27.840 I want you to play with me - Wheel of Weather! 16:27.840 --> 16:30.400 GAME SHOW JAUNTY MUSIC Whoo! 16:30.400 --> 16:33.640 So, let's transform me into a game show host 16:33.640 --> 16:36.560 and let's play this amazing game. 16:36.560 --> 16:40.280 OK, you guys in the audience, you all have cards. 16:40.280 --> 16:44.000 And on one side of the card, it's got blue for Wetter. 16:44.000 --> 16:46.520 So if you think in any given year the weather is going to be 16:46.520 --> 16:49.440 wetter than average, you hold that up. 16:49.440 --> 16:51.720 Yep. And on the other side of your card, 16:51.720 --> 16:53.840 you've got Drier with a yellow sign. Yep? 16:53.840 --> 16:55.960 You're going to hold that up if you think 16:55.960 --> 16:58.920 in any particular year it's going to be drier than average. 16:58.920 --> 17:01.240 And what you can see on my wheel here is 17:01.240 --> 17:03.120 that I've got the same signs. 17:03.120 --> 17:04.720 So if it stops here, the wheel, 17:04.720 --> 17:06.880 this means it's a wetter than average year. 17:06.880 --> 17:09.360 If you held that card up, you get to keep it. 17:09.360 --> 17:12.280 But if you got it wrong, you must put it down. 17:12.280 --> 17:15.280 If you held up your yellow sign and it lands here, that means 17:15.280 --> 17:16.760 you can keep your card. 17:16.760 --> 17:20.640 Green means good growing conditions and we all keep our cards 17:20.640 --> 17:24.400 and the red is the danger zone, the current one degree of warming. 17:24.400 --> 17:27.000 The red means we get one of these extreme events, 17:27.000 --> 17:29.680 something like a flood or a drought, and we all lose a card. 17:29.680 --> 17:33.880 In the game, we're going to play three spins per round 17:33.880 --> 17:36.760 and if you lose two cards in that round, 17:36.760 --> 17:39.440 then you must hold up your red Out sign. 17:39.440 --> 17:42.800 So this represents one degree. 17:42.800 --> 17:45.360 GAME SHOW JINGLE 17:45.360 --> 17:47.320 OK, audience, are you ready? 17:47.320 --> 17:49.080 You've got your cards ready? 17:49.080 --> 17:50.720 Choose now. 17:50.720 --> 17:53.640 OK, Ruben's gone for Drier, Thomas for Wetter, 17:53.640 --> 17:56.880 Milly's Wetter, Ben is Drier. 17:56.880 --> 18:00.400 Jay is Wetter. OK, we've got a good mix going on. 18:00.400 --> 18:04.040 OK, let's spin the wheel and see who's going to get lucky or unlucky. 18:04.040 --> 18:08.280 OK. So there's a really good chance of landing on green but will we...? 18:08.280 --> 18:11.720 Yes! OK, it's been a good year. Everybody keeps their card. 18:11.720 --> 18:13.480 OK, this is a great start. 18:13.480 --> 18:15.120 Are we ready to go again? 18:15.120 --> 18:17.280 Choose now! 18:17.280 --> 18:20.360 GAME SHOW JINGLE OK, cards up. 18:20.360 --> 18:23.720 Maxi's gone for Drier. Could we be lucky twice in a row? 18:23.720 --> 18:26.480 We have been lucky twice in a row. Amazing. 18:26.480 --> 18:28.080 Everybody keeps their card. 18:28.080 --> 18:31.200 OK, so this is the final spin in this round. 18:31.200 --> 18:34.360 You ready? Choose now. 18:34.360 --> 18:36.000 GAME SHOW JINGLE 18:36.000 --> 18:38.360 OK. What to go for? Wetter? Drier? 18:38.360 --> 18:41.160 Sunny days up there for Walter. Very good. 18:41.160 --> 18:43.000 Who else has got his sunshine? 18:43.000 --> 18:46.080 Amelia has got a lovely sunshine. Great. 18:46.080 --> 18:48.280 OK, Fran, we can spin the wheel. 18:48.280 --> 18:50.760 Any sense of where it might land? 18:50.760 --> 18:54.600 Ooh, so it's landed on wetter than average year, 18:54.600 --> 18:57.240 so everybody who guessed correctly that it was going to be 18:57.240 --> 18:59.080 a wetter than average year, well done. 18:59.080 --> 19:03.000 I can see Milly's smiling, Maxi, Thomas, well done. 19:03.000 --> 19:07.320 OK, but let's see how we fared overall for this round, one degree. 19:07.320 --> 19:10.240 Is anybody out? Are you all still in the game? 19:10.240 --> 19:13.360 Everybody's still in. Excellent. Really good news. 19:13.360 --> 19:16.760 OK, so this means, although the weather is unpredictable at 19:16.760 --> 19:20.280 one degree of warming, most of us, in fact in this case, 19:20.280 --> 19:23.880 all of you made it through the year OK and produced the food 19:23.880 --> 19:26.080 that you needed to be able to sell. 19:26.080 --> 19:29.160 So we're going to play the game again, 19:29.160 --> 19:31.920 but this time we're going to play at three degrees. 19:31.920 --> 19:34.480 GAME SHOW JINGLE 19:34.480 --> 19:36.880 Choose now. GAME SHOW JINGLE 19:36.880 --> 19:39.280 OK, get those cards up. Time to decide. 19:39.280 --> 19:41.640 Ooh, lots of Driers over here. 19:41.640 --> 19:44.960 So this time, because we're at three degrees, we've upped the uncertainty 19:44.960 --> 19:47.040 and the unpredictability of the weather. 19:47.040 --> 19:49.920 So the chances of getting a wetter or drier than average year 19:49.920 --> 19:53.920 have increased. Ooh, and it is a wetter than average year. 19:53.920 --> 19:56.920 OK, so Florence, you chose correctly. 19:56.920 --> 20:00.040 So did Jacob, Jay and Max. 20:00.040 --> 20:01.640 Well done. 20:01.640 --> 20:04.440 But that was only the first spin, so we can play again. 20:04.440 --> 20:06.920 OK, are you ready? Choose now. 20:06.920 --> 20:09.880 GAME SHOW JINGLE OK, get those cards up. 20:09.880 --> 20:11.400 Get those cards up. 20:11.400 --> 20:13.600 OK, a good mix of Driers and Wetters again this time. 20:13.600 --> 20:16.080 Oh, wetter than average again. 20:16.080 --> 20:18.720 So, Fern, you are lucky, you keep your card. 20:18.720 --> 20:20.520 Well done, you chose correctly. 20:20.520 --> 20:22.840 And we have a good few people that are out. 20:22.840 --> 20:25.400 They've lost both cards already. Oooh! 20:25.400 --> 20:28.880 But we've still got some of you available for one more spin. 20:28.880 --> 20:30.760 Are you ready? Choose now. 20:30.760 --> 20:32.920 GAME SHOW JINGLE 20:32.920 --> 20:35.720 OK, have you made your decisions? Let me look around the screens. 20:35.720 --> 20:37.360 Yes, everybody has made a decision. 20:37.360 --> 20:38.960 OK, Fran, give it a spin. 20:38.960 --> 20:41.600 Oooooh. 20:41.600 --> 20:43.640 What's it going to be this time? 20:43.640 --> 20:45.720 Oh, drier than average. 20:45.720 --> 20:49.440 So, Ruben, good guess. Fern, good guess. 20:49.440 --> 20:52.360 Oh, we've got more Outs springing up all over the place. 20:52.360 --> 20:54.920 Oh, no, Walter, you're out. 20:54.920 --> 20:59.120 Wow. So if I look around now at our audience, at all of your screens, 20:59.120 --> 21:01.400 I see that at three degrees, 21:01.400 --> 21:05.840 many of you were not able to make it through, you lost your harvest 21:05.840 --> 21:09.120 and maybe your livelihood, too. That's so sad 21:09.120 --> 21:10.640 and this is the reality. 21:10.640 --> 21:13.640 If we allow warming to this amount, to three degrees, 21:13.640 --> 21:17.560 it gets really hard to make the right choices as a farmer. 21:17.560 --> 21:20.440 Thank you for playing the game. 21:20.440 --> 21:23.920 And whilst that was a really fun way to learn about the impacts 21:23.920 --> 21:27.760 of climate change, the underlying message is a really important one. 21:27.760 --> 21:31.840 At two degrees and more of warming, hundreds of millions of people 21:31.840 --> 21:34.640 are exposed to food insecurity, 21:34.640 --> 21:37.920 and farmers in the UK will struggle to make a living. 21:37.920 --> 21:41.320 The International Panel on Climate Change, the IPCC, 21:41.320 --> 21:44.080 which is made up of some of the leading climate scientists 21:44.080 --> 21:47.480 right around the world, tells us that in order to keep safe, 21:47.480 --> 21:52.720 we need to keep warming to below 1.5 degrees above pre-industrial levels. 21:53.880 --> 21:58.040 The difference between 1.5 and 2 degrees may not seem like a lot, 21:58.040 --> 22:01.280 just half a degree, but it's pretty significant. 22:01.280 --> 22:06.920 At 1.5 degrees, it's predicted that we will lose 70 to 90% 22:06.920 --> 22:10.760 of our coral reefs, but that rises to over 99% 22:10.760 --> 22:12.920 at 2 degrees of warming. 22:12.920 --> 22:18.120 And likewise, an extra half a degree of warming between 1.5 and 2 22:18.120 --> 22:22.280 exposes hundreds of millions of people to hunger, 22:22.280 --> 22:25.720 to poverty and to water insecurity. 22:25.720 --> 22:29.160 So what can we do to reduce greenhouse gas emissions 22:29.160 --> 22:31.600 and to stop our planet from warming any more? 22:31.600 --> 22:35.400 Well, let's go have a look and see what's happening in our atmosphere. 22:35.400 --> 22:38.560 So, this net represents our atmosphere. 22:38.560 --> 22:42.440 And as you can see, there's black balls of carbon dioxide 22:42.440 --> 22:46.520 falling into it. We've got this relentless stream of carbon dioxide 22:46.520 --> 22:48.800 coming into our atmosphere. 22:48.800 --> 22:52.200 And what we also have is a natural absorption 22:52.200 --> 22:56.920 and removal of carbon dioxide by the oceans and the land down here. 22:56.920 --> 22:59.360 These are the balls that I'm taking out. 22:59.360 --> 23:01.960 This is the natural storage by our planet. 23:01.960 --> 23:05.240 But as you can see, there's way more going in than are coming out. 23:05.240 --> 23:08.920 And what we need to do, to hold global warming to safe levels 23:08.920 --> 23:12.400 is, we have to balance the amount of carbon dioxide that's going in 23:12.400 --> 23:15.720 with the amount of carbon dioxide that we're taking out. 23:15.720 --> 23:18.080 And the first thing we need to do to do that 23:18.080 --> 23:20.280 is to reduce our emissions. 23:20.280 --> 23:23.240 So what we're going to do is look at how to do that 23:23.240 --> 23:25.760 and we're going to start in the electricity sector. 23:25.760 --> 23:28.720 So, at the moment, because we still produce a lot of our electricity 23:28.720 --> 23:32.600 from fossil fuels, it's responsible for 25% 23:32.600 --> 23:35.480 of global greenhouse gas emissions. 23:35.480 --> 23:38.800 And if we look at what's going on in the UK at the moment, 23:38.800 --> 23:42.000 we can see where our electricity is coming from. 23:42.000 --> 23:46.600 So, this is from yesterday, and yesterday, 24% of our electricity 23:46.600 --> 23:51.240 was coming from renewable resources, from wind and from solar. 23:51.240 --> 23:53.920 But yesterday was not a very windy day, 23:53.920 --> 23:57.760 so the difference had to be made up with fossil fuels, a lot of gas, 23:57.760 --> 24:01.320 even some coal producing the energy that we need. 24:01.320 --> 24:06.200 But on average this year, the good news is that 37% 24:06.200 --> 24:09.480 of our electricity was coming from renewable resources. 24:09.480 --> 24:11.880 So we have the capacity to do a lot more. 24:11.880 --> 24:15.880 We really know a lot already about renewable energy and how to do it. 24:15.880 --> 24:17.800 And what we want to get closer to 24:17.800 --> 24:20.640 is what we had on one day this year where we had 60% 24:20.640 --> 24:23.480 of our energy coming from renewable resources. 24:23.480 --> 24:26.040 So, this is an area that's really exciting 24:26.040 --> 24:29.160 because we have the technology, we know what to do. 24:29.160 --> 24:31.800 We just need to produce a lot more renewable energy. 24:31.800 --> 24:34.440 And, of course, the thing about renewable energy is 24:34.440 --> 24:37.880 we have to figure out how to store it so we can use it 24:37.880 --> 24:40.960 on these days, like yesterday, when the wind isn't blowing 24:40.960 --> 24:43.440 and the sun wasn't very sunny. 24:43.440 --> 24:46.520 And what we want to do then is to either store that energy 24:46.520 --> 24:48.880 in a battery. So you all know about batteries, 24:48.880 --> 24:52.160 they can hold energy, but they lose their charge over time. 24:52.160 --> 24:57.920 So another way of storing energy is to convert excess renewable energy, 24:57.920 --> 25:00.920 say, for example, from this lovely wind turbine here, 25:00.920 --> 25:06.040 to convert that excess energy into a gas that we can store safely 25:06.040 --> 25:08.960 and store even from this year to next year. 25:08.960 --> 25:12.680 So what we're going to do here is we're going to do an experiment 25:12.680 --> 25:16.560 and we are going to turn electricity from our wind turbine 25:16.560 --> 25:19.320 into a gas that we can store. 25:19.320 --> 25:21.560 So we're going to do this through 25:21.560 --> 25:23.040 a process called electrolysis. 25:23.040 --> 25:25.640 So we're going to use the electricity coming from 25:25.640 --> 25:28.280 the wind turbine to perform this process 25:28.280 --> 25:31.640 where we're going to split water, H2O, 25:31.640 --> 25:35.160 into two gases - hydrogen and oxygen. 25:35.160 --> 25:38.400 OK, they're going to flow out of this tube here where 25:38.400 --> 25:40.760 they're all making, already making little bubbles 25:40.760 --> 25:44.120 in the soapy water. OK? 25:44.120 --> 25:46.360 So I'm going to just see if I can scoop some 25:46.360 --> 25:48.960 of these up, so we can get a closer look at the gases. 25:48.960 --> 25:51.760 So I'm going to put on my ear defenders, because we're going to do 25:51.760 --> 25:55.680 a little experiment with these and I'm going to wet my hands. 25:55.680 --> 25:58.920 All right, I'm going to try and scoop up a big handful 25:58.920 --> 26:00.800 of these bubbles. 26:00.800 --> 26:04.120 Oh, I've got a good big handful. I'm very pleased with this. 26:04.120 --> 26:06.600 And let's see what happens. 26:06.600 --> 26:08.840 OK, let's do a little countdown from five, everybody. 26:08.840 --> 26:10.680 Five... 26:10.680 --> 26:15.360 ALL: ..four, three, two, 26:15.360 --> 26:16.800 one. 26:16.800 --> 26:20.200 LOUD POP Whoa! Did you see that? 26:20.200 --> 26:24.040 Wow. All of that energy. 26:24.040 --> 26:26.160 Hydrogen is combining back with oxygen 26:26.160 --> 26:28.880 and giving us what we want, lots of energy, 26:28.880 --> 26:32.120 and the only by-product is water. 26:32.120 --> 26:35.840 And because we made this oxygen from a renewable energy, 26:35.840 --> 26:39.560 it's completely pollution-free, but it is explosive. 26:39.560 --> 26:43.160 So to find out if there are safe ways for storing this fuel, 26:43.160 --> 26:46.720 please welcome Dr Enass Abo-Hamed. 26:46.720 --> 26:48.960 APPLAUSE 26:51.000 --> 26:54.400 Enass, you're very welcome. Hello, Tara. 26:54.400 --> 26:56.880 So, tell me, why are you such a fan of hydrogen? 26:56.880 --> 26:59.840 Oh, I'm a big fan of the hydrogen molecule. 26:59.840 --> 27:02.160 It's a really interesting molecule. 27:02.160 --> 27:05.800 First, it's the smallest molecule in the universe 27:05.800 --> 27:10.160 and yet, it has got the potential to solve the biggest problem 27:10.160 --> 27:13.360 that we have in the world, which is climate change. 27:13.360 --> 27:15.040 And why is that? 27:15.040 --> 27:20.120 Because hydrogen has got a lot of energy density in it, 27:20.120 --> 27:23.320 it's a leading candidate for that. 27:23.320 --> 27:28.520 So we can generate and store a lot of energy and hydrogen, 27:28.520 --> 27:34.360 and we would not need to produce emissions 27:34.360 --> 27:38.760 when we burn it or when we convert it electrochemically 27:38.760 --> 27:41.480 into electricity, because of the simple reason 27:41.480 --> 27:44.160 that it doesn't have any carbon to start with. 27:44.160 --> 27:46.760 So that's a very elegant solution. It's fantastic. 27:46.760 --> 27:49.600 So it's a pollution-free energy source. 27:49.600 --> 27:51.840 So tell me, this is your machine. 27:51.840 --> 27:55.720 How is it storing hydrogen safely and what are you doing with it? 27:55.720 --> 27:59.760 So what we do here in terms of storing the hydrogen safely 27:59.760 --> 28:02.640 is that we simply don't store it as gas. 28:02.640 --> 28:05.080 What we do is we avoid that process, 28:05.080 --> 28:09.040 convert the hydrogen chemically into solid state. 28:09.040 --> 28:13.440 And I have here a bag, I have the material that we actually use 28:13.440 --> 28:15.160 in this reactor. 28:15.160 --> 28:18.680 It's a small amount of chemical powders 28:18.680 --> 28:22.560 that when we expose it to hydrogen, it absorbs a huge amount of it. 28:22.560 --> 28:26.640 Wow. For example, in this reactor, 28:26.640 --> 28:31.240 we can store 2,000 litres of hydrogen at a pressure 28:31.240 --> 28:33.640 that is equivalent to the coffee machine 28:33.640 --> 28:35.240 that we have in our kitchens. 28:35.240 --> 28:37.560 So totally safe to have it here. 28:37.560 --> 28:40.360 And then, this hydrogen is here, so whenever we want to, 28:40.360 --> 28:42.280 we can turn it back into electricity. Exactly. 28:42.280 --> 28:44.000 Can we do that right now? Yes. 28:44.000 --> 28:47.120 So we have the hydrogen here stored in solid state. Mm-hm. 28:47.120 --> 28:51.600 When we want electricity out of it, we will release it back to its free 28:51.600 --> 28:55.800 form, which is the molecule gas, convert that electrochemically 28:55.800 --> 28:58.440 using a fuel cell, which we have here... Wow. 28:58.440 --> 29:01.800 ..and that will basically give us power. 29:01.800 --> 29:04.960 Excellent. So can we turn it on? Yeah, let's turn it on. Go for it. 29:04.960 --> 29:07.000 MACHINE BEEPS 29:08.840 --> 29:13.000 Oh! Just like that! It's so amazing! It doesn't make any noise yet, 29:13.000 --> 29:16.160 it is producing the energy already to turn on our hydrogen sign. 29:16.160 --> 29:20.000 So it is safe, clean and it doesn't have any noise. 29:20.000 --> 29:21.840 It's amazing. I love it. 29:21.840 --> 29:25.120 So what else can we get this amazing device to power up? 29:25.120 --> 29:27.920 We have some things here, Enass, that will be typical 29:27.920 --> 29:29.600 in any teenager's bedroom, 29:29.600 --> 29:34.880 so we can turn them all on with this amazing gas whenever we want to. 29:34.880 --> 29:38.880 But, Enass, is it just electricity? What more can we do with hydrogen? 29:38.880 --> 29:41.040 So this is just one example of... 29:41.040 --> 29:43.760 All the electricity that we have in this small unit, 29:43.760 --> 29:46.720 we could basically use it to power our homes 29:46.720 --> 29:48.640 or what's in our homes. 29:48.640 --> 29:51.960 Today, we can't do it, but it's coming in the future 29:51.960 --> 29:55.560 because we're really interested to decarbonise our energy. 29:55.560 --> 29:58.640 But this isn't the only place where we can actually 29:58.640 --> 30:02.280 reduce our emissions without affecting our productivity. 30:02.280 --> 30:07.040 On the road, for example, the long distance that we could achieve 30:07.040 --> 30:10.920 with hydrogen if we compare it, for example, to electric batteries, 30:10.920 --> 30:15.680 they cannot hold enough energy for as long, 30:15.680 --> 30:19.560 and hydrogen is a much better candidate at doing that 30:19.560 --> 30:24.000 if we wanted to have, like, a very long trip and not having to stop 30:24.000 --> 30:26.520 multiple times on the road to charge. 30:26.520 --> 30:30.120 So the opportunities are so many with hydrogen, and I can see 30:30.120 --> 30:33.400 how certainly it's going to be part of a zero-carbon future for us. 30:33.400 --> 30:35.520 Enass, thank you so much for joining us. 30:35.520 --> 30:37.680 Thank you very much, Tara, for having me. 30:37.680 --> 30:40.040 APPLAUSE 30:44.720 --> 30:48.120 Although hydrogen is expensive to produce at the moment, 30:48.120 --> 30:52.160 it can help us to store energy and we can turn it into electricity 30:52.160 --> 30:54.520 to fuel trains, trucks and buses. 30:54.520 --> 30:57.720 We can even use it to power planes. 30:57.720 --> 31:02.400 In fact, this year, the first-ever passenger hydrogen electric plane 31:02.400 --> 31:04.680 flew right here in the United Kingdom. 31:04.680 --> 31:07.840 And I'm so excited for all of you to think that when you grow up, 31:07.840 --> 31:10.880 you'll be able to fly to see your family and friends 31:10.880 --> 31:12.840 without any pollution. 31:12.840 --> 31:16.720 So, what else can we do to reduce the amount of carbon dioxide 31:16.720 --> 31:18.800 that we're putting into the atmosphere? 31:18.800 --> 31:23.680 Well, another really important sector is agriculture. 31:23.680 --> 31:28.240 So that involves food production and also land use change. 31:28.240 --> 31:31.200 And it's a little bit harder to reduce our emissions 31:31.200 --> 31:33.080 from agriculture and food production 31:33.080 --> 31:35.920 because we're not just talking about fossil fuels. 31:35.920 --> 31:40.240 We'll also have to look at other emissions that come from 31:40.240 --> 31:45.000 clearing land, from the livestock that we breed, from food waste 31:45.000 --> 31:48.040 and even from the fertiliser that we put on the ground. 31:48.040 --> 31:51.640 So let's have a think and a look into the carbon footprint 31:51.640 --> 31:53.680 of our food. 31:53.680 --> 31:58.200 And to do that, please welcome, from the Great British Bake Off 31:58.200 --> 32:00.080 Lottie Bedlow. 32:00.080 --> 32:02.360 APPLAUSE 32:02.360 --> 32:05.400 Lottie, you're so welcome. Hello. Thank you. 32:05.400 --> 32:07.800 And you've brought me some bread. I have. 32:07.800 --> 32:09.560 Did you bake this this morning? 32:09.560 --> 32:12.480 I baked this very lovingly myself for you this morning. 32:12.480 --> 32:14.520 Look, it looks fantastic. I love bread. 32:14.520 --> 32:17.960 So, Lottie, have you ever thought about the carbon footprint of bread? 32:17.960 --> 32:21.000 I can't say I have. No, I don't think many people do. No. 32:21.000 --> 32:24.680 So, the carbon footprint of the average loaf of white bread, 32:24.680 --> 32:28.320 just like this, is 1,200 grams of CO2 equivalent. 32:28.320 --> 32:31.880 It's CO2 equivalent because there's methane and nitrous oxide 32:31.880 --> 32:34.840 and other things in there, too, but we convert it all into CO2 32:34.840 --> 32:37.080 to make it a little bit easier. OK. 32:37.080 --> 32:40.040 But you may notice I have a lot of black balls here. 32:40.040 --> 32:44.280 I have noticed. We've basically said the carbon footprint of that bread 32:44.280 --> 32:47.440 is the equivalent of these 100 black balls. OK. 32:47.440 --> 32:49.480 And what I would love you to help me to do, 32:49.480 --> 32:54.080 because you're good at baking, is to help me reverse bake this bread. 32:54.080 --> 32:56.720 So we're going to go backwards through the life 32:56.720 --> 33:00.040 of this loaf of bread. OK. Yeah? It sounds confusing. 33:00.040 --> 33:03.240 So you've worked hard to bake it and now... You're going to undo it. 33:03.240 --> 33:06.680 OK. So what was the last thing you did with the bread? 33:06.680 --> 33:09.040 The last thing I did was to take it out of the oven. 33:09.040 --> 33:12.800 So would you like to try out this lovely oven behind you? I shall. OK. 33:12.800 --> 33:15.920 So, while Lottie's putting it in the oven, 33:15.920 --> 33:18.520 obviously you have to turn an oven on to make bread. 33:18.520 --> 33:20.440 What temperature did you bake it at? 33:20.440 --> 33:22.800 Well, the first 15 minutes at 200 degrees 33:22.800 --> 33:25.680 and then the next 30 minutes at 170. 33:25.680 --> 33:28.160 OK. And how long was it in the oven? That's maths. 33:28.160 --> 33:31.120 So that's 45 minutes. 45 minutes. 33:31.120 --> 33:35.040 OK, so that's 45 minutes of an oven using electricity... Yeah. 33:35.040 --> 33:37.960 ..and electricity creates emissions. Yeah. 33:37.960 --> 33:42.200 And so baking the bread, that's using energy while it's in the oven 33:42.200 --> 33:46.680 for 45 minutes, so that accounts for 16% of the carbon footprint 33:46.680 --> 33:50.360 of the bread. So that's our first 16 balls in there. 33:50.360 --> 33:53.120 OK. Lottie, do you like toast? I love toast. 33:53.120 --> 33:55.480 What do you put on yours? I let it go cold, 33:55.480 --> 33:57.920 then I put a thick layer of butter, then Marmite 33:57.920 --> 34:00.040 and you should see your teeth marks in it. 34:00.040 --> 34:02.360 I just think that's all wrong. 34:02.360 --> 34:04.640 I like my toast hot, butter, marmalade. 34:04.640 --> 34:07.880 But anyway, it turns out that having toast is quite extravagant 34:07.880 --> 34:09.720 because freezing and toasting of bread, 34:09.720 --> 34:13.560 that accounts for another 25%. Oh. OK. Yeah? 34:13.560 --> 34:15.560 So obviously toasters uses a lot of energy. 34:15.560 --> 34:19.360 So there's another 25% gone in, it's filling up already. 34:19.360 --> 34:21.040 It's not even baked. 34:21.040 --> 34:24.480 OK, so let's work backwards from it was in the oven, 34:24.480 --> 34:27.440 before you put it in the oven... Oh, the ingredients. 34:27.440 --> 34:29.400 What ingredients did you make it with? 34:29.400 --> 34:31.520 So, I used flour, 34:31.520 --> 34:34.240 water and yeast. 34:35.760 --> 34:38.280 OK, so how much do you think about flour? 34:38.280 --> 34:40.760 I think about flour quite a lot. 34:40.760 --> 34:43.120 Yeah? Do you have favourite kinds of flour? 34:43.120 --> 34:46.480 Erm, so bread flour is what I'd use for bread. Plain flour, self-raising, 34:46.480 --> 34:49.080 all different types. And where do you buy it? 34:49.080 --> 34:50.920 I buy it in my supermarket. Yeah. Perfect. 34:50.920 --> 34:53.240 Most people buy flour in the supermarket. 34:53.240 --> 34:55.560 So, flour has to be milled. Mm-hm. 34:55.560 --> 34:59.440 So we have created you a very magic reverse milling machine. 34:59.440 --> 35:01.200 Fantastic. Thank you. 35:01.200 --> 35:04.120 So how this works, because it's a bit tricky and fantastically messy, 35:04.120 --> 35:07.600 is you turn it upside down because it's reverse milling. Yeah. 35:07.600 --> 35:10.840 OK. Then you pour some of your flour from your ramekin in the top. 35:10.840 --> 35:13.640 Just some of it? Just some of it, a good old dollop of it. 35:13.640 --> 35:17.280 And then you turn the handle and you see what magic happens. 35:17.280 --> 35:20.520 Oh, it's exciting. So turn the handle and... 35:20.520 --> 35:22.360 Woohoo! 35:22.360 --> 35:26.080 ..it turns back into grains of wheat. Wheat. Yeah. So fantastic. 35:26.080 --> 35:29.320 So that is the grains of wheat that flour comes from. 35:29.320 --> 35:33.080 OK. So that process of milling... You're making a great mess. 35:33.080 --> 35:35.960 Yeah, just flip it over quick, it's OK. Leave that there. 35:35.960 --> 35:37.600 That process of milling, that takes... 35:37.600 --> 35:39.760 That uses energy, it happens in a big factory. 35:39.760 --> 35:42.120 That's another three balls gone in. OK. 35:42.120 --> 35:46.040 OK, tremendous. So we're back at, we're back at wheat grains. Yeah. 35:46.040 --> 35:48.600 So wheat grains come from wheat, 35:48.600 --> 35:51.240 so a farmer had to grow the wheat in his field 35:51.240 --> 35:53.440 and then we have to transport it to the factory 35:53.440 --> 35:56.360 to be milled, and then we'll also have to transport it, I guess, 35:56.360 --> 35:59.160 from there to get to your supermarket where you bought it. 35:59.160 --> 36:03.040 So that transport accounts for another four balls. Yeah. 36:03.040 --> 36:06.080 OK. So we're definitely filling it up now. 36:06.080 --> 36:09.200 We are. OK, but there's still, we're still not even halfway really 36:09.200 --> 36:13.200 when you think about it. So the wheat has to be grown. Mm-hm. 36:13.200 --> 36:15.760 Have you ever...? You haven't grown wheat in your garden? 36:15.760 --> 36:17.880 Not recently, no. Not a big wheat grower. 36:17.880 --> 36:20.800 You're not a big wheat grower. No. OK, so, but there are plenty 36:20.800 --> 36:22.800 of farmers in the UK that grow wheat. 36:22.800 --> 36:26.000 80% of the flour in the UK is grown with UK wheat. 36:26.000 --> 36:28.400 So that's good. So we need some soil, I guess. 36:28.400 --> 36:29.960 Would you give that a stir? 36:29.960 --> 36:34.320 So I guess the farmer would need soil, sunshine, rain, 36:34.320 --> 36:37.440 and then, I think more than likely, they will also use some of this, 36:37.440 --> 36:39.960 which is a fertiliser. Fertiliser, yeah. 36:39.960 --> 36:42.120 So would you mix a bit of that in with the soil? Sure. 36:42.120 --> 36:45.320 So fertiliser takes a lot of energy to make, 36:45.320 --> 36:47.440 so that's producing emissions. 36:47.440 --> 36:50.920 And then, when we use the fertiliser, it also releases a greenhouse gas 36:50.920 --> 36:52.760 called nitrous oxide. 36:52.760 --> 36:56.240 And nitrous oxide is a really strong greenhouse gas. 36:56.240 --> 36:59.000 It's 300 times stronger than carbon dioxide. 36:59.000 --> 37:03.000 And what all of that means is that growing the raw materials 37:03.000 --> 37:07.080 for bread comes up to a whopping 41% of... Yeah, that's a lot. 37:07.080 --> 37:08.400 That's a lot, isn't it? 37:08.400 --> 37:11.080 So I have to get this whole bucket and I have to not spill any. 37:11.080 --> 37:15.240 OK. So that's all those 41 balls in. 37:15.240 --> 37:17.640 All right. I think we must be nearly there. 37:17.640 --> 37:19.720 How are you feeling about your loaf of bread? 37:19.720 --> 37:22.280 Yeah, I need to think more about baking my loaves of bread, 37:22.280 --> 37:24.480 but I feel, I feel like this is good. 37:24.480 --> 37:27.040 It's good to know where it comes from and it's good to know 37:27.040 --> 37:28.640 the process it goes through. Yeah. 37:28.640 --> 37:31.520 And the thing is, making anything has a carbon footprint, 37:31.520 --> 37:33.360 but it's just understanding. 37:33.360 --> 37:36.280 It's really interesting to understand the different parts of it 37:36.280 --> 37:37.560 and where it comes from. 37:37.560 --> 37:39.560 Now, if you in the audience are any good at maths, 37:39.560 --> 37:41.920 you may have noticed that this does not add up to 100, 37:41.920 --> 37:44.800 if anybody has been doing the arithmetic in your head. 37:44.800 --> 37:47.400 So there's six remaining balls 37:47.400 --> 37:49.440 in my caddy down here. 37:50.760 --> 37:53.680 Now, would you waste even a crumb of a loaf of bread 37:53.680 --> 37:55.800 that Lottie made you? No. 37:55.800 --> 37:59.240 No. I'm certainly not, I'm going to eat every scrap of it, 37:59.240 --> 38:02.080 but we do waste a lot of bread, yeah? 38:02.080 --> 38:05.360 We do. And that bread produces greenhouse gas emissions 38:05.360 --> 38:09.000 when it goes into a landfill, it releases methane. 38:09.000 --> 38:11.440 And actually, we waste one third of the food in the world. Wow. 38:11.440 --> 38:13.440 It's absolutely desperate, 38:13.440 --> 38:15.880 and it produces 8% of global greenhouse gas emissions 38:15.880 --> 38:17.800 come from food waste. 38:17.800 --> 38:22.080 So the final six balls... Yeah. ..come from food waste. 38:22.080 --> 38:26.000 So anything we can do, all of us, to reduce that waste, would be good. 38:26.000 --> 38:29.080 That's it, Lottie, I think we've come to the end of it. 38:29.080 --> 38:32.560 I am not going to put Marmite on the bread that you brought me. 38:32.560 --> 38:35.960 Well, you're missing out. I know. But thank you for joining us. 38:35.960 --> 38:38.480 Thank you for helping me to reverse bake bread. 38:38.480 --> 38:40.480 Thank you. You're welcome. 38:40.480 --> 38:43.080 Can we have a round of applause for Lottie, everybody? 38:43.080 --> 38:45.920 APPLAUSE 38:48.800 --> 38:52.520 We've just seen the significant amount of greenhouse gas emissions 38:52.520 --> 38:56.080 that go up into our atmosphere from food waste. 38:56.080 --> 38:58.120 So what can we do about it? 38:58.120 --> 39:00.960 Well, first thing is, I guess we should waste less food 39:00.960 --> 39:04.160 and then, for that unavoidable food waste, like the peelings 39:04.160 --> 39:07.640 and the scraps, we need to try and get those into a food waste bin 39:07.640 --> 39:10.480 where we can, so they don't end up in landfill. 39:10.480 --> 39:13.520 Now, have you ever stopped to think about what happens to that 39:13.520 --> 39:16.320 food waste when it goes away in the bin? What happens to it? 39:16.320 --> 39:18.360 Where does it go? 39:18.360 --> 39:22.080 So it might go for industrial composting, where it's broken down 39:22.080 --> 39:26.560 in the presence of oxygen to produce a lovely fertile compost. 39:26.560 --> 39:30.640 Or it can go for a process called anaerobic digestion, 39:30.640 --> 39:33.720 where it's broken down in the absence of oxygen. 39:33.720 --> 39:37.920 And we sent our cameras to see how this process works. 39:40.240 --> 39:43.440 So, at the moment, we're standing in our reception hall. 39:43.440 --> 39:45.920 So the waste is collected from wherever it's created, 39:45.920 --> 39:49.520 that might be your home, it might be a supermarket, retail, 39:49.520 --> 39:52.400 hospitality, a pub, a restaurant, 39:52.400 --> 39:55.200 and it will be brought here and it's then put into that big hopper 39:55.200 --> 39:59.560 in the corner, and there we've got what we call a hammermill. 39:59.560 --> 40:02.640 So it's something with big hammers that will basically smash the food 40:02.640 --> 40:05.600 waste and separate the packaging from the food waste itself. 40:08.600 --> 40:11.600 So once the material has had the packaging removed, 40:11.600 --> 40:15.160 it goes through a series of shredders or macerators 40:15.160 --> 40:17.560 in order to make the particles very small. 40:17.560 --> 40:20.680 From that point onwards, the food waste is always 40:20.680 --> 40:23.160 in a pipe, or in a pump or in a tank. 40:24.880 --> 40:27.680 The first tank that it goes into is a little bit like your 40:27.680 --> 40:30.400 food cupboard at home, where you would store your food 40:30.400 --> 40:32.600 before it's being fed to the digester. 40:32.600 --> 40:35.160 And this is where the magic really happens. 40:35.160 --> 40:38.200 These are what we call digesters, and in these tanks 40:38.200 --> 40:40.800 are hundreds of different types of bacteria 40:40.800 --> 40:44.720 who all work together to break down the food waste into biogas. 40:44.720 --> 40:48.520 So the gas leaves the gas holder and goes through a series 40:48.520 --> 40:51.480 of these pipes, which then feeds into our engine. 40:51.480 --> 40:55.840 And in the engine, the methane part of the biogas is converted 40:55.840 --> 40:58.720 into heat, in the form of hot water and electricity. 40:58.720 --> 41:01.360 So, of the electricity that we produce, 41:01.360 --> 41:04.640 about 10% of it is used to run this site 41:04.640 --> 41:08.480 and the remaining 90% is fed into the National Grid. 41:09.680 --> 41:13.280 The digestate, which is the other end product, is really valuable, 41:13.280 --> 41:15.520 what we call a bio fertiliser. 41:15.520 --> 41:17.800 The fertiliser is picked up by local farmers 41:17.800 --> 41:19.680 who apply it to their land. 41:19.680 --> 41:23.200 And in doing that, they don't have to use bought-in fertiliser. 41:25.080 --> 41:30.240 Please welcome Becky Greaves to tell us more about anaerobic digestion. 41:30.240 --> 41:32.280 Becky, lovely to see you. 41:32.280 --> 41:34.280 APPLAUSE 41:35.520 --> 41:40.040 So, Becky, we've learned quite a lot about methane as a greenhouse gas 41:40.040 --> 41:43.440 in the Christmas lectures this year, and how potent it is 41:43.440 --> 41:45.720 when it gets up into our atmosphere. 41:45.720 --> 41:48.440 Can you tell us how you prevent methane from getting up 41:48.440 --> 41:50.400 into the atmosphere? 41:50.400 --> 41:54.360 So, we really carefully control the feed to our digesters 41:54.360 --> 41:57.800 to make sure that we produce the methane at the same rate that we can 41:57.800 --> 41:59.640 use it through our engines. 41:59.640 --> 42:03.600 And the tanks and the pipes that you saw in that video are all sealed 42:03.600 --> 42:07.320 so there's no way that that methane can get up into the atmosphere. 42:07.320 --> 42:11.320 What do you do with it then? You produce energy, electricity with it? 42:11.320 --> 42:13.600 How much electricity can you produce? 42:13.600 --> 42:15.560 So, on the video, you saw a large lorry 42:15.560 --> 42:17.720 reversing into our reception hall. 42:17.720 --> 42:21.080 Typically, a lorry of that size would hold about 25 tonnes 42:21.080 --> 42:24.120 of food waste. And once that's digested through our process, 42:24.120 --> 42:27.960 it will produce enough electricity to fuel an average household 42:27.960 --> 42:29.960 for over two years. 42:29.960 --> 42:31.880 Wow, that's really impressive. 42:31.880 --> 42:34.320 And, Becky, we saw at the end of the clip 42:34.320 --> 42:36.480 the bio fertiliser that you're making. 42:36.480 --> 42:39.320 How can that help us to reduce the greenhouse gas emissions 42:39.320 --> 42:41.200 from agriculture? 42:41.200 --> 42:44.400 So, the farmer would have to apply some sort of fertiliser 42:44.400 --> 42:46.560 to the wheat in order to grow it. 42:46.560 --> 42:50.320 If we go back to your example of the growing the wheat for bread 42:50.320 --> 42:54.080 that you used earlier, and so by applying bio fertiliser, 42:54.080 --> 42:58.120 we're giving that wheat those exact same nutrients, but actually, 42:58.120 --> 43:01.680 we're not using those mineral or those synthetic fertilisers, 43:01.680 --> 43:04.320 which, as you say, produce greenhouse gases 43:04.320 --> 43:05.800 for their production. 43:05.800 --> 43:09.200 And to put it into context, that lorry that you saw, the digester 43:09.200 --> 43:13.640 or the digestate that was produced from that food waste would be enough 43:13.640 --> 43:17.720 to fertilise the wheat to produce 5,000 loaves of bread. 43:17.720 --> 43:21.320 What's really good about this process is that it's a closed loop. 43:21.320 --> 43:25.240 So, actually, if you throw away a mouldy loaf of bread, we can turn it 43:25.240 --> 43:29.600 into bio fertiliser and grow wheat to produce more bread. 43:29.600 --> 43:32.480 But more importantly, we also produce the electricity 43:32.480 --> 43:35.680 to bake that bread and for you to use it at home 43:35.680 --> 43:38.440 and turn it into toast. Becky, that is amazing. 43:38.440 --> 43:41.600 It's just a whole lot of win-wins in this solution 43:41.600 --> 43:44.280 that you've told us about. Thank you so much for joining us. 43:44.280 --> 43:45.960 Thank you for having me. 43:45.960 --> 43:48.240 APPLAUSE 43:49.760 --> 43:52.520 So, we know what to do to reduce the emissions 43:52.520 --> 43:54.280 going into our atmosphere. 43:54.280 --> 43:57.800 We just need to stop burning fossil fuels and keep them in the ground, 43:57.800 --> 44:00.600 and we need to reduce the emissions from agriculture 44:00.600 --> 44:02.000 and food production. 44:02.000 --> 44:04.400 We just need to do more of it. 44:04.400 --> 44:08.360 But reducing emissions on their own isn't going to be enough. 44:08.360 --> 44:11.560 I'm going to take a look again at our atmosphere. 44:11.560 --> 44:15.000 So, what we've managed to do now by reducing emissions 44:15.000 --> 44:18.880 is to slow the flow of carbon dioxide into our atmosphere. 44:18.880 --> 44:21.280 But as you can see, it's still building up. 44:21.280 --> 44:23.360 We're still making the problem worse. 44:23.360 --> 44:28.080 So what we also need to do is remove carbon dioxide from the atmosphere. 44:28.080 --> 44:31.760 And our best ally in doing that is nature. 44:33.080 --> 44:36.200 As you remember with Chris and Helen, 44:36.200 --> 44:40.280 we learned about the natural ability of our oceans and the land 44:40.280 --> 44:42.200 to store carbon. 44:42.200 --> 44:45.960 And so, if we protect nature, 44:45.960 --> 44:48.880 we protect ecosystems and restore them, 44:48.880 --> 44:52.680 we can remove CO2 from the atmosphere 44:52.680 --> 44:56.200 and that is what we need to do to be able to achieve 44:56.200 --> 44:59.560 1.5 degrees of warming. 44:59.560 --> 45:03.400 So nature is our best ally in this process. 45:03.400 --> 45:07.640 You probably know that trees have a great potential 45:07.640 --> 45:10.680 to store carbon and keep us safe. 45:10.680 --> 45:13.520 But have you ever thought about our soil? 45:13.520 --> 45:15.600 So, soil holds 45:15.600 --> 45:20.280 1,500 billion tonnes 45:20.280 --> 45:22.320 of carbon dioxide. 45:22.320 --> 45:28.080 So much. And within that, peatlands, which cover only 3% of the planet, 45:28.080 --> 45:31.960 they hold one third of all that soil carbon. 45:31.960 --> 45:34.280 They're so amazing. 45:34.280 --> 45:36.400 But don't take my word for it. 45:36.400 --> 45:40.560 To learn more about peat and its wonderful ability to store carbon, 45:40.560 --> 45:43.440 please welcome Professor Andy Baird. 45:43.440 --> 45:45.600 APPLAUSE 45:48.960 --> 45:52.080 Andy, thanks so much for joining us. 45:52.080 --> 45:55.640 Erm, can you tell me what makes peatlands so amazing 45:55.640 --> 45:58.400 and why are they such amazing carbon stores? 45:58.400 --> 46:00.920 Hi, Tara. Yes, they are amazing. 46:00.920 --> 46:04.840 I mean, peatlands have been forming since the end of the last ice age 46:04.840 --> 46:06.760 and over the thousands and thousands 46:06.760 --> 46:08.600 of years that have elapsed since then, 46:08.600 --> 46:12.440 they've been slowly accumulating carbon, so that now we get 46:12.440 --> 46:16.200 to the present day and they are huge global carbon stores. 46:16.200 --> 46:20.040 And, Andy, can we use this cross section of peat that you were kind 46:20.040 --> 46:24.000 enough to send me, to explain this storage process? 46:24.000 --> 46:26.520 Maybe starting from the bottom of the sample. 46:26.520 --> 46:29.520 Yeah, of course. This sample was taken from a peat bog 46:29.520 --> 46:31.560 that is six and a half metres deep. 46:31.560 --> 46:34.400 Now, we've only got a shallow bit of peat here, 46:34.400 --> 46:38.400 but even at a depth of 40 centimetres, this peat is old. 46:38.400 --> 46:42.240 So, at that depth, at the bottom of the core, the plants that form 46:42.240 --> 46:45.160 that peat, they were growing at a time that Shakespeare 46:45.160 --> 46:49.560 was writing his last play, so it's 400 years old. 46:49.560 --> 46:51.840 If we move up in the profile to about mid profile, 46:51.840 --> 46:55.080 so about 20 centimetres below the surface, 46:55.080 --> 46:57.560 we're still below the water table there. 46:57.560 --> 47:00.960 And being below the water table means that decay of the peat 47:00.960 --> 47:04.800 is a lot slower. So this is part of the long-term carbon store 47:04.800 --> 47:06.600 that peatlands have. 47:06.600 --> 47:09.200 And then if we move up to the surface, 47:09.200 --> 47:11.280 we can see where all the dynamics happen, 47:11.280 --> 47:13.160 we can see sphagnum mosses. 47:13.160 --> 47:17.080 Now, sphagnum mosses, each year, they sort of grow up vertically 47:17.080 --> 47:19.480 and the lower part of the sphagnum, 47:19.480 --> 47:21.840 it dies and it gets added to the peat, 47:21.840 --> 47:23.720 it becomes part of the peatland. 47:23.720 --> 47:27.160 And if the amount of dead sphagnum moss being added to the peat 47:27.160 --> 47:30.120 is more than all the decay in the profile below, 47:30.120 --> 47:32.520 the peat in there will get bigger and bigger. 47:32.520 --> 47:35.280 It will accumulate carbon. Wow. 47:35.280 --> 47:38.440 So it's this whole process of keeping the peat wet 47:38.440 --> 47:42.400 that is helping us to ensure that it stores carbon. 47:42.400 --> 47:45.160 Absolutely, yes. You need to keep peatlands wet. 47:45.160 --> 47:48.440 And that reminds me of two really interesting statistics. 47:48.440 --> 47:52.720 A 50 centimetre layer of peatlands, a little bit more than that core, 47:52.720 --> 47:57.200 a 50 centimetre layer per hectare, holds more carbon 47:57.200 --> 48:00.200 than a hectare of tropical rainforest. 48:00.200 --> 48:02.560 And if we think about all the world's forests, 48:02.560 --> 48:04.600 they contain a lot of carbon, 48:04.600 --> 48:07.000 but peatlands contain twice as much carbon 48:07.000 --> 48:09.240 as all the world's forests put together. 48:09.240 --> 48:10.920 They really are so amazing. 48:10.920 --> 48:14.200 But then, Andy, what happens if a peatland dries out? 48:14.200 --> 48:17.240 If you drain a peatland, what you do is you lower the water table, 48:17.240 --> 48:20.800 and as the water table lowers, you allow air to get into the peat 48:20.800 --> 48:24.440 and that means oxygen, and that speeds up the rate of decay 48:24.440 --> 48:27.840 perhaps by ten times, even more than 100 times. 48:27.840 --> 48:32.040 And decay produces carbon dioxide and that goes into the atmosphere. 48:32.040 --> 48:33.800 So peatlands that are drained, 48:33.800 --> 48:35.800 they're big leakers of carbon dioxide 48:35.800 --> 48:37.920 into the atmosphere, if you like. 48:37.920 --> 48:40.880 And, Andy, why would we be draining peatlands? 48:40.880 --> 48:42.320 Why are we drying them out? 48:42.320 --> 48:43.760 That's a good question. 48:43.760 --> 48:46.200 Well, drainage happens for a variety of reasons, 48:46.200 --> 48:48.320 sometimes to grow trees for afforestation, 48:48.320 --> 48:51.520 so commercial forestry, sometimes for agriculture, 48:51.520 --> 48:55.520 and also to make peat extraction more straightforward, easier. 48:55.520 --> 48:58.360 And people extract peat for a range of reasons, 48:58.360 --> 49:01.000 but one of the biggest reasons is to produce compost 49:01.000 --> 49:02.880 for your gardens. Oh, my goodness. 49:02.880 --> 49:06.600 It's so bonkers that we're digging up this amazing carbon store 49:06.600 --> 49:09.160 to use it in our gardens. I agree. 49:09.160 --> 49:11.160 I think it's absolutely bonkers myself. 49:11.160 --> 49:15.360 And I think of it as being a little bit like dredging up all the coral 49:15.360 --> 49:18.400 in the Great Barrier Reef, crushing it and then sprinkling it 49:18.400 --> 49:20.760 on your garden to make it look more pretty. 49:20.760 --> 49:24.200 It's just madness, it's destroying a really important ecosystem. 49:24.200 --> 49:27.120 And I think peatlands are as important as our coral reefs. 49:27.120 --> 49:29.000 So if they're that important, Andy, 49:29.000 --> 49:30.960 what should we be doing to protect them? 49:30.960 --> 49:33.440 I think there's two things - the peatlands that are already 49:33.440 --> 49:36.160 in a natural condition, already wet, we need to keep them that way. 49:36.160 --> 49:38.400 We mustn't drain them, we mustn't damage them. 49:38.400 --> 49:41.200 And then the peatlands that are drained and currently leaking 49:41.200 --> 49:43.520 loads of carbon dioxide into the atmosphere, 49:43.520 --> 49:45.640 we've got to reverse that process. 49:45.640 --> 49:48.680 We need to block the drains, get them wetter, and they'll leak 49:48.680 --> 49:51.240 a lot less carbon dioxide into the atmosphere. 49:51.240 --> 49:55.640 Andy, thank you so much for sharing all this information about peatlands 49:55.640 --> 49:57.920 with us. Everybody, Andy Baird. 49:57.920 --> 50:00.200 APPLAUSE 50:00.200 --> 50:04.120 So Andy told us that the most important things we can do 50:04.120 --> 50:07.440 for our peatlands is, first of all, to protect the ones that we have, 50:07.440 --> 50:11.800 but secondly, we need to rewet those degraded peatlands 50:11.800 --> 50:15.200 so that they don't lose any more carbon dioxide. 50:15.200 --> 50:18.920 OK, it's only by rewetting them that they can continue to hold on 50:18.920 --> 50:20.960 to that carbon dioxide. 50:20.960 --> 50:24.080 But a bonus of this is that if we start to restore 50:24.080 --> 50:27.560 and rehabilitate our wetlands, then the vegetation will start 50:27.560 --> 50:31.080 to grow again over time, they'll be recolonised by things 50:31.080 --> 50:33.360 like sphagnum moss. 50:33.360 --> 50:37.120 And what that means is that our peatlands will, over time, 50:37.120 --> 50:41.080 over decades, between now, between now and you becoming my age, 50:41.080 --> 50:44.880 they'll start to become stores of carbon dioxide again. 50:44.880 --> 50:49.000 They'll be removing it from the atmosphere and storing it safely 50:49.000 --> 50:50.600 in the peat. 50:50.600 --> 50:55.400 So peatlands are one of the most amazing ways that we can remove 50:55.400 --> 50:59.240 carbon from the atmosphere and store it safely. 50:59.240 --> 51:02.520 So let's go back and have a look at our atmosphere. 51:02.520 --> 51:08.440 So, at the moment, we have slowed the flow of carbon dioxide 51:08.440 --> 51:10.360 into the atmosphere. 51:10.360 --> 51:13.240 We store more carbon by restoring peatlands 51:13.240 --> 51:16.320 and our natural ecosystems. 51:16.320 --> 51:20.080 There is still some carbon dioxide left in our atmosphere, 51:20.080 --> 51:22.680 and that means that the warming is going to continue 51:22.680 --> 51:26.000 and we're going to have to learn how to adapt to climate change, 51:26.000 --> 51:29.080 how to cope with the impacts that it's going to bring. 51:29.080 --> 51:31.200 So we need to understand climate impacts, 51:31.200 --> 51:33.160 we need to plan for them, 51:33.160 --> 51:37.480 we need to prepare by building things like flood defences. 51:37.480 --> 51:39.640 But we also need to invest in people 51:39.640 --> 51:43.200 and make people better able to cope with climate change. 51:43.200 --> 51:46.160 Welcome to Taraville. 51:46.160 --> 51:50.000 Taraville is a small town on the coast of the UK 51:50.000 --> 51:51.840 that's vulnerable to flooding. 51:51.840 --> 51:55.320 And let me introduce you to two Taras that live there. 51:55.320 --> 51:57.840 Tara 1, which is this bucket. 51:57.840 --> 52:01.520 Tara 1 is our happy-go-lucky student. 52:01.520 --> 52:03.600 She comes from a well-to-do family. 52:03.600 --> 52:06.400 She's living in the halls of residence and having a great time 52:06.400 --> 52:09.600 at university and she's in really good health. 52:09.600 --> 52:13.640 Tara 2, meanwhile, is our struggling student. 52:13.640 --> 52:18.000 She's living at home with her parents and her elderly grandad. 52:18.000 --> 52:21.400 She's holding down a part-time job to make ends meet, 52:21.400 --> 52:24.360 and she suffers from asthma, which is accentuated 52:24.360 --> 52:27.560 by the poor air quality where she lives. 52:27.560 --> 52:32.120 So, one dark December night, 52:32.120 --> 52:35.040 Taraville is hit by a flood. 52:36.840 --> 52:38.760 Now, the flood has hit. 52:38.760 --> 52:42.840 Immediately, both Taras are down in the red zone down here. 52:42.840 --> 52:45.920 They're both at risk from the flood. 52:45.920 --> 52:48.080 But let's rewind a little. 52:48.080 --> 52:50.720 So Tara 1 got a warning. 52:50.720 --> 52:55.000 Her mum, who is friends with the mayor and really well connected, 52:55.000 --> 52:58.880 gave her a call and said, "Tara, I think it's going to flood." 52:58.880 --> 53:01.920 Nobody gave Tara 2 a warning. 53:01.920 --> 53:05.200 Tara 1 was able to prepare for the flood. 53:05.200 --> 53:09.160 She took all her belongings upstairs to her friend's room 53:09.160 --> 53:12.240 on the second floor and kept them safe. 53:12.240 --> 53:15.040 Tara 2 made no preparations. 53:15.040 --> 53:17.680 At the same time, she was tidying up after dinner, 53:17.680 --> 53:20.640 checking on her grandad and going to bed oblivious. 53:20.640 --> 53:23.720 Tara 1 when the flood hit, 53:23.720 --> 53:27.280 she was upstairs having a slumber party with her friend. 53:27.280 --> 53:32.520 She was starting to be really out of danger and in the green zone. 53:32.520 --> 53:35.600 Tara 2, meanwhile, when the flood hit, 53:35.600 --> 53:38.880 dirty floodwater came through her house. 53:38.880 --> 53:41.920 Everybody rushed downstairs to try and get grandad 53:41.920 --> 53:43.760 up the stairs to safety. 53:43.760 --> 53:46.960 All that rushing and the stress accentuated Tara's asthma 53:46.960 --> 53:49.960 and it was just terrible. 53:49.960 --> 53:53.040 By one in the morning, Tara 1 is snoring, 53:53.040 --> 53:56.360 she's completely safe in her halls of residence. 53:56.360 --> 54:00.200 Meanwhile, Tara 2 and her family are being rescued in a boat 54:00.200 --> 54:03.280 and taken to an emergency shelter. 54:03.280 --> 54:07.440 The next morning, Tara 1 checks her room downstairs, 54:07.440 --> 54:10.840 sees there's some minor damage, but, you know, she's got savings 54:10.840 --> 54:13.960 so she can replace things and she had contents insurance 54:13.960 --> 54:16.320 on her belongings so she's fine. 54:16.320 --> 54:18.480 Tara bounces back quickly. 54:18.480 --> 54:22.080 She's up in the green zone, she's no longer at risk. 54:23.280 --> 54:26.400 But Tara 2, she can't even go home the next day. 54:26.400 --> 54:28.480 Her house is ruined. 54:28.480 --> 54:32.120 Her family don't have any savings in the bank, and they weren't able 54:32.120 --> 54:35.520 to get insurance on their house because they live in the flood zone. 54:35.520 --> 54:39.160 Tara 2 has to drop out of college to get another job. 54:39.160 --> 54:43.280 Grandad is in hospital with pneumonia, and it's several years 54:43.280 --> 54:46.320 before her family get back to normal. 54:46.320 --> 54:48.440 She continues to live at risk. 54:49.960 --> 54:53.600 So what can we do to make this sad story better? 54:53.600 --> 54:57.720 How can we make Tara 2 less vulnerable to these floods, 54:57.720 --> 55:00.120 to these impacts of climate change? 55:00.120 --> 55:02.640 Well, let's think about some things we could do. 55:02.640 --> 55:06.960 Number one, what if the town council in Taraville got their act together 55:06.960 --> 55:09.680 and built some flood defences? 55:09.680 --> 55:13.080 And what if they rehabilitated the wetlands 55:13.080 --> 55:16.080 so that they were able to protect natural, 55:16.080 --> 55:19.160 to create natural protection from flooding? 55:19.160 --> 55:23.120 What if they put in place an early warning system 55:23.120 --> 55:26.440 and Tara was able to get a text message on a phone 55:26.440 --> 55:29.040 telling her there was a flood coming? 55:29.040 --> 55:31.920 That would make Tara less vulnerable. 55:31.920 --> 55:33.960 And if Tara got that message in time, 55:33.960 --> 55:36.160 she would be able to prepare. 55:36.160 --> 55:39.000 She'd be able to get all of their belongings upstairs 55:39.000 --> 55:43.600 in their house, and she'd be able to arrange for grandad to go 55:43.600 --> 55:47.560 and stay in a care home for the night, so he'd be out of danger. 55:47.560 --> 55:51.600 And she would use her social connections to call a friend 55:51.600 --> 55:55.120 to come and pick her up and take her and her parents to safety 55:55.120 --> 55:57.400 for the night. 55:57.400 --> 56:01.840 And this way, when Tara would return to her house the next day, 56:01.840 --> 56:04.920 she would find that the damage had been limited, 56:04.920 --> 56:08.600 not too bad at all, and what was damaged would have been covered 56:08.600 --> 56:13.280 by the insurance that she was able to buy because she was eligible 56:13.280 --> 56:17.240 for insurance now that the flood defences had been built. 56:17.240 --> 56:22.360 As we take these steps to make Tara more resilient, she's less at risk, 56:22.360 --> 56:25.920 she comes up to being almost in the same category 56:25.920 --> 56:28.000 that Tara 1 was. 56:28.000 --> 56:31.840 And the point of this demonstration is that if we give everybody 56:31.840 --> 56:34.840 opportunity, it makes them more resilient 56:34.840 --> 56:37.200 to the impacts of climate change. 56:38.320 --> 56:42.800 And so, as we've seen today, it's not just enough 56:42.800 --> 56:47.160 to reduce our emissions of greenhouse gases and carbon dioxide, 56:47.160 --> 56:50.920 we also have to take and remove carbon dioxide 56:50.920 --> 56:53.960 from the atmosphere and store it away safely, 56:53.960 --> 56:56.320 using nature as our ally. 56:56.320 --> 57:01.240 And we need to adapt to the impacts of climate change 57:01.240 --> 57:02.960 that we have already caused. 57:02.960 --> 57:07.360 But what I want you to know, as young people listening here today, 57:07.360 --> 57:09.520 is that we know what to do. 57:09.520 --> 57:11.640 We just need to do a lot more of it 57:11.640 --> 57:14.400 and we need to do it with greater urgency. 57:14.400 --> 57:17.360 We have the solutions, we have the knowledge, 57:17.360 --> 57:20.120 we have nature and science on our side. 57:21.920 --> 57:24.360 But I am just one scientist 57:24.360 --> 57:29.640 and we are all looking at the same thing, yet we see it differently. 57:29.640 --> 57:34.760 I see that the energy we can access and the atoms we have are limited, 57:34.760 --> 57:37.720 but human creativity is infinite. 57:37.720 --> 57:40.640 And I see that we're not separate to the planet, 57:40.640 --> 57:43.600 we're part of it, we're not just users of it. 57:43.600 --> 57:48.120 And I see that we have a choice about how we live on it. 57:48.120 --> 57:51.520 Sometimes in the face of huge problems like climate change, 57:51.520 --> 57:53.600 it can feel like our personal actions are too small 57:53.600 --> 57:55.560 to make a difference. 57:55.560 --> 57:58.680 But we can protect what we understand. 57:58.680 --> 58:01.000 And we will protect what we care about. 58:04.680 --> 58:09.280 It's up to us to take action and to use our voices 58:09.280 --> 58:14.120 and every time we do, we create a ripple that keeps on growing. 58:14.120 --> 58:16.280 It starts here. 58:16.280 --> 58:18.960 APPLAUSE