0:00:01.040,0:00:06.884 Yogi Berra, a US baseball player[br]and philosopher, said, 0:00:06.884,0:00:10.793 "If we don't know where we're going,[br]we might not get there." 0:00:11.171,0:00:15.797 Accumulating scientific knowledge[br]is giving us greater insights, 0:00:15.797,0:00:21.023 greater clarity into what our future[br]might look like in a changing climate 0:00:21.023,0:00:23.653 and what that could mean for our health. 0:00:23.653,0:00:27.443 I'm here to talk about a related aspect 0:00:27.443,0:00:32.001 on how our emissions of greenhouse gases[br]from burning of fossil fuels 0:00:32.001,0:00:35.941 is reducing the nutritional[br]quality of our food. 0:00:37.226,0:00:39.482 We'll start with the food pyramid. 0:00:39.482,0:00:41.594 You all know the food pyramid. 0:00:41.594,0:00:44.055 We all need to eat a balanced diet. 0:00:44.055,0:00:45.697 We need to get proteins. 0:00:45.697,0:00:48.943 We need to get micronutrients.[br]We need to get vitamins. 0:00:48.943,0:00:51.921 And so this is way for us[br]to think about how to make sure 0:00:51.921,0:00:54.220 we get what we need every day 0:00:54.220,0:00:56.270 so we can grow and thrive. 0:00:56.438,0:00:59.116 So we eat not just because we need to, 0:00:59.116,0:01:00.854 we also eat for enjoyment. 0:01:00.854,0:01:03.682 Bread, pasta, pizza, 0:01:03.682,0:01:05.512 there's a whole range of foods 0:01:05.512,0:01:07.717 that are culturally important. 0:01:07.717,0:01:09.940 We enjoy eating these. 0:01:09.940,0:01:12.503 And so they're important for our diet, 0:01:12.503,0:01:15.470 but they're also important[br]for our cultures. 0:01:15.980,0:01:21.515 Carbon dioxide has been increasing since[br]the start of the Industrial Revolution, 0:01:21.515,0:01:26.934 increasing from about[br]280 parts per million to over 410 today, 0:01:26.934,0:01:28.825 and it continues to increase. 0:01:28.825,0:01:33.284 The carbon that plants need to grow[br]comes from this carbon dioxide. 0:01:33.537,0:01:36.432 They bring it into the plant,[br]they break it apart 0:01:36.432,0:01:38.258 into the carbon itself, 0:01:38.258,0:01:40.638 and they use that to grow. 0:01:40.638,0:01:43.290 They also need nutrients from the soil. 0:01:43.290,0:01:47.323 And so yes, carbon dioxide is plant food. 0:01:48.469,0:01:53.590 And this should be good news,[br]of rising carbon dioxide concentrations, 0:01:53.590,0:01:57.352 for food security around the world, 0:01:57.352,0:02:01.700 making sure that people[br]get enough to eat every day. 0:02:01.911,0:02:07.090 About 820 million people in the world[br]don't get enough to eat every day. 0:02:07.090,0:02:10.811 So there's a fair amount written[br]about how higher CO2 0:02:10.811,0:02:13.784 is going to help with[br]our food security problem. 0:02:13.784,0:02:18.840 We need to accelerate our progress[br]in agricultural productivity, 0:02:18.840,0:02:23.309 to feed the nine to 10 billion people[br]who will be alive in 2050 0:02:23.309,0:02:26.201 and to achieve the Sustainable[br]Development Goals, 0:02:26.201,0:02:28.091 particularly the Goal Number 2, 0:02:28.091,0:02:31.181 that is on reducing food insecurity, 0:02:31.181,0:02:32.709 increasing nutrition, 0:02:32.709,0:02:36.451 increasing access to the foods[br]that we need for everyone. 0:02:36.451,0:02:40.806 We know that climate change[br]is affecting agricultural productivity. 0:02:40.806,0:02:43.683 The Earth has warmed[br]about one degree Centigrade 0:02:43.683,0:02:45.696 since pre-industrial times. 0:02:45.696,0:02:49.766 That is changing local temperature[br]and precipitation patterns, 0:02:49.766,0:02:54.111 and that has consequences[br]for the agricultural productivity 0:02:54.111,0:02:56.506 in many parts of the world. 0:02:56.506,0:02:59.820 And it's not just local changes[br]in temperature and precipitation, 0:02:59.820,0:03:01.070 it's the extremes, 0:03:01.070,0:03:05.482 Extremes in terms of heat waves,[br]floods and droughts 0:03:05.482,0:03:08.738 are significantly affecting productivity. 0:03:09.903,0:03:13.306 And that carbon dioxide, 0:03:13.306,0:03:15.578 besides making plants grow, 0:03:15.578,0:03:18.910 has other consequences as well, 0:03:18.910,0:03:21.909 that plants when they have[br]higher carbon dioxide, 0:03:21.909,0:03:26.245 increase the synthesis of carbohydrates,[br]sugars and starches, 0:03:26.245,0:03:31.020 and they decrease the concentrations[br]of protein and critical nutrients, 0:03:31.020,0:03:37.459 and this is very important for how we[br]think about food security going forward. 0:03:38.659,0:03:42.418 A couple of nights ago[br]in the table talks on climate change, 0:03:42.418,0:03:46.234 someone said that they're[br]a five-seventh optimist, 0:03:46.234,0:03:48.791 that they're an optimist[br]five days of the week, 0:03:48.791,0:03:52.719 and this is a topic for other two days. 0:03:53.065,0:03:55.296 When we think about micronutrients, 0:03:55.296,0:04:00.049 almost all of them are affected[br]by higher CO2 concentrations. 0:04:00.049,0:04:02.539 Two in particular are iron and zinc. 0:04:02.539,0:04:06.652 When you don't have enough iron,[br]you can develop iron deficiency anemia. 0:04:06.652,0:04:09.647 It's associated with fatigue,[br]shortness of breath, 0:04:09.647,0:04:12.927 and some fairly serious[br]consequences as well. 0:04:12.927,0:04:17.279 When you don't have enough zinc, 0:04:17.279,0:04:18.722 you can have a loss of appetite. 0:04:18.722,0:04:19.468 It is a significant[br]problem around the world. 0:04:19.468,0:04:22.584 There's about one billion people[br]who are zinc-deficient. 0:04:22.584,0:04:25.463 It's very important[br]for maternal and child health. 0:04:25.463,0:04:27.450 It affects development. 0:04:27.995,0:04:31.835 The B-vitamins are critical[br]for a whole range of reasons. 0:04:31.835,0:04:34.845 They help convert our food into energy. 0:04:34.845,0:04:36.803 They're important for the functions 0:04:36.803,0:04:40.255 of many of the physiologic[br]activities in our bodies, 0:04:40.255,0:04:42.933 and when you have[br]higher carbon in a plant, 0:04:42.933,0:04:44.614 you have less nitrogen, 0:04:44.614,0:04:46.530 and you have less B-vitamins. 0:04:46.954,0:04:48.494 And it's not just us. 0:04:48.494,0:04:50.256 Cattle are already being affected, 0:04:50.256,0:04:53.655 because the quality[br]of their forage is declining. 0:04:53.952,0:04:57.436 In fact, this affects[br]every consumer of plants. 0:04:57.436,0:05:01.109 And give a thought to, for example,[br]our pet cats and dogs. 0:05:01.109,0:05:04.601 If you look on the label[br]of most of the pet and dog food, 0:05:04.601,0:05:09.016 there's a significant amount[br]of grain in those foods. 0:05:09.453,0:05:11.639 So this affects everyone. 0:05:11.639,0:05:13.968 How do we know that this is a problem? 0:05:13.968,0:05:15.969 We know from field studies, 0:05:15.969,0:05:19.208 and we know from experimental[br]studies in laboratories. 0:05:19.208,0:05:20.696 In the field studies -- 0:05:20.696,0:05:24.548 and I'll focus primarily[br]on wheat and on rice -- 0:05:24.548,0:05:27.777 there's fields, for example, of rice 0:05:27.777,0:05:29.743 that are divided into different plots, 0:05:29.743,0:05:32.777 and the plots are all the same. 0:05:32.777,0:05:34.260 The soil's the same, 0:05:34.260,0:05:38.035 the precipitation is the same,[br]everything's the same 0:05:38.035,0:05:41.867 except carbon dioxide[br]is blown over some of the plots. 0:05:42.563,0:05:44.668 And so you can compare 0:05:44.668,0:05:48.234 what it looks like[br]under today's conditions 0:05:48.234,0:05:52.335 and under carbon dioxide conditions[br]later in the century. 0:05:53.128,0:05:56.318 I was part of one of the few[br]studies that have done this. 0:05:56.318,0:06:00.912 We looked at 18 rice lines[br]in China and in Japan, 0:06:00.912,0:06:03.562 and grew them under conditions[br]that you would expect 0:06:03.562,0:06:05.764 later in the century. 0:06:05.764,0:06:09.434 And when you look at the results, 0:06:09.434,0:06:12.373 the white bar is today's conditions, 0:06:12.373,0:06:16.260 the red bar is conditions[br]later in the century. 0:06:16.956,0:06:20.346 So protein declines about 10 percent, 0:06:20.346,0:06:24.189 iron about eight percent,[br]zinc about five percent. 0:06:25.231,0:06:27.974 These don't sound like really big changes, 0:06:27.974,0:06:31.816 but when you start thinking[br]about the poor in every country 0:06:31.816,0:06:33.964 who primarily eat starch, 0:06:33.964,0:06:37.550 that this will put people[br]who are on the edge 0:06:37.550,0:06:39.792 over the edge into frank deficiencies, 0:06:39.792,0:06:42.145 creating all kinds of health problems. 0:06:42.145,0:06:46.008 The situation is more significant[br]for the B-vitamins. 0:06:46.308,0:06:50.036 When you look at[br]vitamin B1 and vitamin B2, 0:06:50.036,0:06:52.679 there's about a 17 percent decline. 0:06:52.679,0:06:57.720 Pantothenic acid, vitamin B5[br]is about a 13 percent decline, 0:06:57.720,0:07:01.109 and folate is about a 30 percent decline, 0:07:01.109,0:07:04.824 and these are averages over[br]the various experiments that were done. 0:07:05.359,0:07:08.782 Folate is critical for child development. 0:07:08.782,0:07:10.915 Pregnant women who don't get enough folate 0:07:10.915,0:07:14.234 are at much higher risk[br]of having babies with birth defects. 0:07:14.234,0:07:19.595 So these are very serious[br]potential consequences for our health 0:07:19.595,0:07:22.190 as CO2 continues to rise. 0:07:23.509,0:07:24.941 In another example, 0:07:24.941,0:07:28.142 this is modeling work that was done[br]by [?] and his colleagues 0:07:28.142,0:07:33.996 taking a look at this chain[br]from higher CO2 to lower iron and zinc, 0:07:33.996,0:07:36.494 and they only looked at iron and zinc, 0:07:36.494,0:07:38.433 to various health outcomes, 0:07:38.433,0:07:41.578 and they looked at malaria,[br]diarrheal disease, pneumonia, 0:07:41.578,0:07:43.798 iron deficiency anemia, 0:07:43.798,0:07:47.984 and looked at what[br]the consequences could be in 2050, 0:07:47.984,0:07:49.998 and the darker the color in this, 0:07:49.998,0:07:52.114 the larger the consequences. 0:07:52.114,0:07:54.937 So you can see the major impacts 0:07:54.937,0:07:57.212 in Asia and in Africa, 0:07:57.212,0:08:00.527 but also note that in countries[br]such as the United States 0:08:00.527,0:08:02.057 and countries in Europe, 0:08:02.057,0:08:04.472 the populations also could be affected. 0:08:05.203,0:08:09.501 They estimated about[br]125 million people could be affected. 0:08:09.501,0:08:13.786 They also modeled what would be[br]the most effective interventions, 0:08:13.786,0:08:18.086 and their conclusion was[br]reducing our greenhouse gases, 0:08:18.086,0:08:21.854 getting our greenhouse gas emissions[br]down by midcentury 0:08:21.854,0:08:25.070 so we don't have to worry so much[br]about these consequences 0:08:25.070,0:08:26.584 later in the century. 0:08:28.822,0:08:31.351 These experiments, these modeling studies 0:08:31.351,0:08:34.273 did not take climate change[br]itself into account. 0:08:34.273,0:08:37.695 They just focused on[br]the carbon dioxide component. 0:08:37.695,0:08:39.419 So when you put the two together, 0:08:39.419,0:08:43.951 it's expected the impact is much larger[br]than the one I've told you. 0:08:43.951,0:08:46.911 I'd love to be able to tell you right now 0:08:46.911,0:08:52.181 how much the food you had for breakfast,[br]the food you're going to have for lunch, 0:08:52.181,0:08:54.650 has shifted from what[br]your grandparents ate 0:08:54.650,0:08:57.260 in terms of its nutritional quality, 0:08:57.260,0:08:58.837 but I can't. 0:08:59.384,0:09:01.940 We don't have the research on that. 0:09:01.940,0:09:05.428 I'd love to tell you how much[br]current food insecurity 0:09:05.428,0:09:07.465 is affected by these changes, 0:09:07.465,0:09:08.938 but I can't. 0:09:08.938,0:09:11.691 We don't have the research on that either. 0:09:12.198,0:09:15.903 There's a lot that needs[br]to be known in this area, 0:09:15.903,0:09:19.860 including what the possible[br]solutions could be. 0:09:19.860,0:09:23.034 We don't know exactly[br]what those solutions are, 0:09:23.034,0:09:25.768 but we've got a range of options. 0:09:25.768,0:09:28.311 We've got advancements in technologies. 0:09:28.311,0:09:31.632 We've got plant breeding.[br]We've got bio-fortification. 0:09:31.632,0:09:33.466 Soils could make a difference. 0:09:33.466,0:09:38.313 And, of course, it would be very helpful[br]to know how these changes could affect 0:09:38.313,0:09:39.669 our future health 0:09:39.669,0:09:43.587 and the health of our children[br]and the health of our grandchildren. 0:09:43.587,0:09:46.660 And these investments take time. 0:09:46.660,0:09:50.443 It will take time to sort[br]all of these issues out. 0:09:50.443,0:09:55.178 There is no national entity[br]or business group 0:09:55.178,0:09:57.483 that is funding this research. 0:09:57.799,0:10:03.249 We need these investments critically[br]so that we do know where we're going. 0:10:04.250,0:10:06.681 In the meantime, what we can do 0:10:06.681,0:10:12.425 is ensure that all people[br]have access to a complete diet, 0:10:12.425,0:10:17.640 not just those in the wealthy parts[br]of the world but everywhere in the world. 0:10:17.640,0:10:22.569 We also individually and collectively need[br]to reduce our greenhouse gas emissions 0:10:22.569,0:10:25.817 to reduce the challenges[br]that will come later in the century. 0:10:26.987,0:10:32.987 It's been said that if you think[br]education is expensive, try ignorance. 0:10:34.334,0:10:36.208 Let's not. 0:10:36.208,0:10:38.994 Let's invest in ourselves, 0:10:38.994,0:10:41.503 in our children, and in our planet. 0:10:41.503,0:10:42.932 Thank you. 0:10:42.932,0:10:47.191 (Applause)