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Climate, C02, Plants and Public Health:Ignorance is not bliss

March 05, 2020

Lewis H. Ziska, PhD, EHS, Mailman School of Public Health, Columbia University.

Sponsored by the Yale Center on Climate Change and Health

ID
4912

Transcript

  • 00:00(students chatting)
  • 00:05- [Kai] Yeah, I think we can start now.
  • 00:08And so welcome everyone to today's seminar,
  • 00:11hosted by the Yale Center on Climate Change and Health.
  • 00:14So, I'm Dr. Kai Chan,
  • 00:18Assistant Professor of the EHS Department.
  • 00:20I'm also the Director of Research for the center.
  • 00:23So today, we are very honored and prepared
  • 00:25to have Dr. Lewis Ziska come to give us today's lecture.
  • 00:31So Dr. Ziska is a professor at the Mailman School
  • 00:35of Public Health at Columbia University.
  • 00:37So before joining Columbia, he was a senior scientist
  • 00:41at the US Department of Agriculture for nearly 25 years.
  • 00:45So he's one of the most leading experts
  • 00:49on the effects of climate change on plants and agriculture.
  • 00:53So, without further ado, let's welcome Dr. Ziska.
  • 00:56(students applauding)
  • 00:59- [Lewis] Thank you, Professor Chan,
  • 01:00I appreciate the opportunity to be here.
  • 01:04The good news is you've got free food.
  • 01:06(students laughing)
  • 01:07The bad news is you've got to listen to me lecture so...
  • 01:13I wanted to look at the nexus between climate change,
  • 01:17rise in carbon dioxide and public health
  • 01:19and just sort of give you a sense of the range
  • 01:23of different consequences associated with it.
  • 01:26So we have the good, we have the bad, and we have the OMG.
  • 01:32So, I want to go through and talk about some of the work
  • 01:35that we've been doing on all of these different aspects.
  • 01:38Before I do that, however, I wanna make sure
  • 01:40that we're all on the same page when it comes
  • 01:43to defining what we mean by climate change.
  • 01:47So, we know that carbon dioxide is going up.
  • 01:52This is a recent Keeling Curve, where you can see
  • 01:56that we're getting close to about 410 parts per million.
  • 02:01In my lifetime, the amount of carbon dioxide is increased
  • 02:04by about 30% and the reason why is not difficult.
  • 02:08It turns out that if you take a carbon source,
  • 02:11fossil fuel source, and you oxidize it, you burn it,
  • 02:15carbon-oxygen, yeah carbon dioxide, who knew?
  • 02:19So, if you look at, this is a little bit out of date,
  • 02:21but if you look at where the carbon dioxide comes from,
  • 02:24again, oxidation of fossil fuels and cement production
  • 02:28in calcium carbonate, one of the offshoots
  • 02:31of calcium carbonate is carbon dioxide.
  • 02:34Land use change, where does it go?
  • 02:36About 50% of it stays in the atmosphere, about 25% of it
  • 02:39goes back in the land through photosynthesis,
  • 02:42and about 25% of it is dissolved into the oceans
  • 02:45where carbon dioxide and water
  • 02:46is formed (mumbling) acid.
  • 02:49Okay, so...
  • 02:52here are as we know,
  • 02:55this particular change is recent.
  • 02:58This is the highest carbon dioxide that we've experienced,
  • 03:01at least in the last million years.
  • 03:03We know where it comes from, where is it gonna go?
  • 03:06Well, depends on which model you happen to believe in.
  • 03:09And I won't go through all the different models.
  • 03:11We'll look at the green one down here.
  • 03:13We'll call this everyone drive a Prius and Hans model,
  • 03:16and that so far is not working out.
  • 03:19We have the business as usual model here,
  • 03:21and that may not be working out because that's depending on
  • 03:25a certain amount of coal usage, and that's been going down,
  • 03:29but there's still a bit of uncertainty about the fact,
  • 03:33particularly in regards to methane,
  • 03:35but there's no question that it's going up.
  • 03:36If we just do the rule of thumb, it's going up
  • 03:38two to three parts per million per year.
  • 03:40We have about 80 years left, so it can range anywhere
  • 03:43from 160 to 240 parts per million higher than it is today.
  • 03:49Okay, so why should you give a flying fig
  • 03:52whether carbon dioxide is 300 or 400 or 500,
  • 03:56what difference does it make, right?
  • 03:58Well, it makes two differences.
  • 03:59The first one has to do with the physical aspects
  • 04:03of increasing these particular gases.
  • 04:06We know that the atmosphere consists of certain gases.
  • 04:10Most of those we are familiar with, but there are two
  • 04:13that we consider to be global warming gases.
  • 04:18What does that mean exactly?
  • 04:19What makes it a global warming gas?
  • 04:22Well, to answer that question,
  • 04:24I will, of course, turn to music.
  • 04:27How many of you have ever played a string instrument?
  • 04:30Excellent, so I'm gonna turn this over to you.
  • 04:34Suppose for the sake of argument
  • 04:36that I tune two strings to the same frequency, okay?
  • 04:41Let's say A 440 Hertz, all right?
  • 04:43So you have two strings
  • 04:44that are tuned to the same frequency,
  • 04:46and I pluck one string, what will the string next to it do?
  • 04:52- [Female Voice] Suddenly vibrate?
  • 04:53- [Lewis] It'll vibrate, it'll resonate, it'll absorb
  • 04:55some of the energy from the first string.
  • 04:57What if I'm a Methodist, will that still work?
  • 05:01- [Student] Yes.
  • 05:03- [Lewis] What if I'm a republican?
  • 05:04(student laughing)
  • 05:06- [Student] Yes.
  • 05:06- [Lewis] Are you telling me that the laws of physics
  • 05:08are independent of religious denomination
  • 05:10and political affiliation?
  • 05:11Oh my god, you have no idea.
  • 05:13(students laughing)
  • 05:14Oh wait, no, that isn't how it works, is it?
  • 05:16Sorry, I've been in DC for too long.
  • 05:19Yeah, no it's absolutely true.
  • 05:20So, what does this have to do
  • 05:22with being a global warming gas?
  • 05:23Well, it turns out that in addition to music,
  • 05:28molecules also resonate.
  • 05:31They don't resonate in the key of A,
  • 05:34but they resonate in the key of infrared, or heat.
  • 05:37So whenever heat is experienced by one of these molecules,
  • 05:41it resonates, it absorbs some of that energy
  • 05:43that would otherwise be lost, does that make sense?
  • 05:48Good, this has taken an entire semester
  • 05:50of physics and atmospheric chemistry
  • 05:51into five minutes so please forgive me.
  • 05:55- [Lewis] So the two major greenhouse gases
  • 05:57are carbon dioxide and water vapor, humidity, if you will.
  • 06:00All right?
  • 06:02So as this change in carbon dioxide occurs,
  • 06:05that's not a bad thing because
  • 06:08there's a natural greenhouse effect.
  • 06:10If there were no carbon dioxide, the average temperature
  • 06:14on the earth would be about minus 80 degrees Celsius.
  • 06:18So, by having carbon dioxide, by having water vapor,
  • 06:22you have a livable environment.
  • 06:25But I think you can see that
  • 06:26this sort of a Goldilocks principle that occurs here, right?
  • 06:29Too little, too much.
  • 06:33So, we're seeing the earth warm up,
  • 06:37but it's not warming up the same everywhere, is it?
  • 06:40Some areas are warming up faster than others.
  • 06:43Why?
  • 06:44Well, if it was the sun, then the equator
  • 06:46would be warming up very fast.
  • 06:49It's not, what's warming up the fastest?
  • 06:53What area of the world is warming up quickly?
  • 06:55- [Male Student] The poles. - [Lewis] The poles.
  • 06:58They get the least amount of sun,
  • 06:59how come they're warming up so quickly?
  • 07:03Wait a minute, I said there were two, there were two
  • 07:06greenhouse gases, weren't there?
  • 07:09And, water vapor's one of the greenhouse gases,
  • 07:12so where on the globe is water vapor dominant,
  • 07:16the dominant greenhouse gas?
  • 07:22Where's the air warming unit?
  • 07:23I'm not trying to trick you.
  • 07:26- [Female Student] Equator? - [Lewis] At the equator.
  • 07:28So at the equatorial regions, where it's warm and wet,
  • 07:33you already have water vapor,
  • 07:34it's the dominant greenhouse gas.
  • 07:36Adding more CO2, yeah, it's gonna get warmer and wetter.
  • 07:39Is it gonna rise very quickly?
  • 07:41No, it takes a lot more energy to move something
  • 07:43that has a lot of water in it, right?
  • 07:45Because water absorbs heat.
  • 07:49Okay, so we got a big change in the tropics.
  • 07:53Where is the air dry
  • 07:56and therefore adding more carbon dioxide would be
  • 07:59the primary driver, in terms of surface temperatures?
  • 08:03You already mentioned one.
  • 08:09The Poles.
  • 08:13When the air is cold, is does not pull a lot of water vapor
  • 08:16and therefore adding more carbon dioxide is going to have
  • 08:19a major effect in terms of surface temperatures.
  • 08:22Where else is the air dry?
  • 08:29- [Student] The surface. - [Lewis] I'm really not
  • 08:29trying to trick you, this is just basic high school biology.
  • 08:33- [Student] The desert.
  • 08:34- [Lewis] Pardon?
  • 08:35- [Student] Someone said desert.
  • 08:36- [Lewis] Deserts, excellent.
  • 08:38Deserts.
  • 08:40So what do we expect to see with more carbon dioxide?
  • 08:41Increased desertification, right?
  • 08:43Deserts are gonna get bigger.
  • 08:46Makes sense so far?
  • 08:48Okay, gonna add a little bit more to this.
  • 08:50If you go up in elevation and altitude,
  • 08:53as you move up in altitude the air becomes dryer,
  • 08:55therefore there is gonna be a major shift
  • 08:57in terms of temperature.
  • 08:59Seasonally, which season, summer or winter,
  • 09:01has the highest humidity?
  • 09:05- [Student] Summer.
  • 09:06- [Lewis] Connecticut, is it hotter and wetter
  • 09:08in July or in December?
  • 09:13- [Student One] December. - [Student Two] July.
  • 09:15- [Lewis] Again, I'm not trying to trick you, okay?
  • 09:16All right, it's July.
  • 09:18The summer is warmer and wetter, so the fact is
  • 09:20that temperature is gonna happen more in the winter
  • 09:23than it is in the summer, and that's what we're seeing okay?
  • 09:27So, here's the technical message.
  • 09:30If water vapor is high, it's the dominant warming gas,
  • 09:34and there's less effect of CO2.
  • 09:37If the water vapor is low, adding more CO2
  • 09:40will have a differential higher effect
  • 09:43with respect to surface temperatures.
  • 09:46Again, I've taken an entire semester and given five minutes,
  • 09:49but you can hopefully adjust to this, there's more to it.
  • 09:53So, let's look at it from the plant biology point of view.
  • 09:56Okay, warmer temperatures, well,
  • 09:59we know that greater temperature increase
  • 10:01with latitude or altitude, based on what I've talked about,
  • 10:04increased desertification, increased drought,
  • 10:07rise in sea levels from increased polar and glacial melt.
  • 10:10Okay?
  • 10:11So, what's warm is gonna get warmer,
  • 10:13what's wet is gonna get wetter,
  • 10:15and we see these changes going on, right?
  • 10:18That's the indirect effect of rise in carbon dioxide.
  • 10:22Now, let me tell you the other direct effect,
  • 10:25or the only direct effect,
  • 10:26and that is plants are essential to life.
  • 10:28What do plants need in order to grow?
  • 10:33- [Student One] Sunlight.
  • 10:34- [Lewis] Sunlight, excellent, thank you so much
  • 10:36for sitting in the front row.
  • 10:38Water, light, nutrients, right?
  • 10:41They need all kinds of nutrients;
  • 10:43your nitrogen, your phosphorous, your potassium.
  • 10:46What's the fourth thing they need?
  • 10:48- [Students] CO2.
  • 10:50- Carbon dioxide, right?
  • 10:54Okay, let's do this as a thought experiment.
  • 10:58Suppose for the sake of argument that phosphorous, okay,
  • 11:02that the amount of phosphorous had gone up
  • 11:04in every soil around the world by 30%.
  • 11:07By 30% in your lifetime.
  • 11:11Would that have an effect on plant biology?
  • 11:15Yeah, of course.
  • 11:17There are over 400, 000 different species of plants.
  • 11:20Would all plants respond the same way to that effect?
  • 11:23- [Student] No.
  • 11:25- [Lewis] And as plants are the foundation or the basis
  • 11:28for life on the planet, for they're
  • 11:30the bottom of the food chain,
  • 11:32are there gonna be ramifications of that?
  • 11:34Oh, hell yes!
  • 11:39Here's one of them, I got this from the ExxonMobil website.
  • 11:44Now that provides strength
  • 11:46but this is lovely fine.
  • 11:48And you can see lovely fine you can (mumbles).
  • 11:52Well look at that, that is so cool.
  • 11:55I've only find Rosemary
  • 11:57when you give it more carbon dioxide.
  • 12:01If you're a forester you understand that the faster
  • 12:03the tree grows the weaker the wood.
  • 12:05But you told me that aside from that wasn't on the website.
  • 12:10Oh, hey,
  • 12:12this is Kazoo.
  • 12:14Anybody from the southern US?
  • 12:16Anybody experienced Kazoo firsthand?
  • 12:18Yeah, I know.
  • 12:19We did not in the front doorstep or in the morning.
  • 12:23This is an invasive vine
  • 12:25and it also responds to carbon dioxide.
  • 12:27Wow, this is one of the worst weeds in the United,
  • 12:30am sorry, I keep saying weeds,
  • 12:32the current administration term is alternative crop.
  • 12:36So I don't wanna confuse anybody, okay?
  • 12:38All right, so this also responds to carbon dioxide.
  • 12:44Well what are the consequences
  • 12:45of this direct effect of rising CO2?
  • 12:48Well, it's a fundamental resource for plant growth
  • 12:50and all plants are gonna be beneficial to human society.
  • 12:53Not all plants respond the same way
  • 12:55and rising CO2 alters
  • 12:56the qualitative components of plants.
  • 13:01Nobody talks about this because CO2
  • 13:03is plant food and everything is wonderful and good,
  • 13:06and everything's gonna be great.
  • 13:08Doesn't work that way.
  • 13:10So let's look at the good.
  • 13:12Let's take the good part first, all right?
  • 13:14All of you are familiar with malaria.
  • 13:17About 400, 000 deaths primarily in
  • 13:20Sub-Saharan, Saharan regions.
  • 13:24It's a tremendous and awful storage disease.
  • 13:30So, one of the ways in which it is dealt with
  • 13:36is through this particular plant.
  • 13:42This is Artemisia annua or sweet Annie, okay?
  • 13:46It has been used in Chinese medicine for hundreds of years
  • 13:50as a means to combat malaria.
  • 13:54It produces this compound artemisinin
  • 13:57which has this wonderful peroxide bridge
  • 14:00which is important in terms of killing Plasmodium,
  • 14:04the carrier for malaria.
  • 14:08So, it is part of what are considered
  • 14:10to be artemisinin combination therapies
  • 14:12which is still the primary means
  • 14:14to respond to malaria globally.
  • 14:16And what they do in this is
  • 14:18they take artemisinin compounds,
  • 14:20they add different one or two longer acting drugs,
  • 14:22usually from the quinine family, they add it
  • 14:25to the artemisinin and that's a means to prevent or
  • 14:28to help you get over the malaria.
  • 14:30And just from a sort of anatomical point of view,
  • 14:35the glandular secretion, the trichomes in artemisia
  • 14:38when you have a little closer look, that's where
  • 14:40your artemisinin is being produced.
  • 14:42Okay.
  • 14:43So obviously, the question I gotta ask is,
  • 14:46if CO2 stimulates plant growth,
  • 14:50what does it do for artemisinin production?
  • 14:53And we worked with a group at Nanjing University
  • 14:57at the National Academy, the Chinese Academy of Sciences.
  • 15:01And they have a FACE of free CO2 enrichment system.
  • 15:05We were looking at the artemisinin content
  • 15:07as a function of carbon dioxide
  • 15:10and function of the carbon:nitrogen ratio.
  • 15:12So you could use this elemental analysis
  • 15:14of carbon and nitrogen as a means
  • 15:15to predict how much our artemisinin
  • 15:18was being produced by give a plant.
  • 15:21And then Chan Jiu who was my colleague there,
  • 15:26went to different herbarium around China
  • 15:29to look at artemisinin, to collect it
  • 15:32and to do this C:M ratio.
  • 15:34So we have collections that vary from
  • 15:371900 to 2005, 2006.
  • 15:42And during this time period, carbon dioxide has risen,
  • 15:47in sort of a logarithmic fashion,
  • 15:48slow at first and then increasing.
  • 15:51Is there a connection between this rise
  • 15:53in carbon dioxide and the change in
  • 15:56the estimated artemisinin concentration produced?
  • 15:59And we think there is.
  • 16:01Here's the carbon dioxide levels here in the curve,
  • 16:04and here is the estimated artemisinin concentration
  • 16:07that we're seeing for this as a function of decade,
  • 16:10as a function of carbon dioxide.
  • 16:13In fact, what they're doing now is that
  • 16:15the are forwarding greenhouses where our AC is growing,
  • 16:20adding more carbon dioxide as a means
  • 16:22to increase artemisinin production now.
  • 16:25So this is a good thing.
  • 16:27It's a way of increasing a chemical compound produced
  • 16:29by leaves that we know has a positive effect with respect
  • 16:33to malarial
  • 16:37concentrations,
  • 16:38trying to cure your malarial symptoms.
  • 16:42So from the good point of view, Artemisia annua by the way,
  • 16:46is a common weed in North America, is a central
  • 16:49pharmacological resource to treat malaria in Africa
  • 16:52Recent increases in atmospheric CO2 are associated with
  • 16:54the increase of a known anti-malarial drug
  • 16:56derived from this plant.
  • 16:58What other plant-based drugs are responding?
  • 17:03Don't know?
  • 17:05You need find out.
  • 17:09Let me give you the bad, okay?
  • 17:12This is something I've been working on for
  • 17:13a number of years and has to do with pollen.
  • 17:15How many of you suffer from seasonal pollen allergies?
  • 17:19Raise your hand, excellent.
  • 17:20Okay, so basically the plants that are
  • 17:23associated with seasonal pollen allergies sort of fall
  • 17:25into three major taxa; you have trees in the spring,
  • 17:28weeds and grasses in the summertime
  • 17:30and Ragweed in the fall (mumbles).
  • 17:34So we went through and looked at how again,
  • 17:37how is carbon dioxide affecting pollen production
  • 17:40from ragweed during sampling of catkins.
  • 17:43Here are some of the early work that we did,
  • 17:45this is great chamber work where we were lowering
  • 17:47the carbon dioxide values to pre-industrial levels
  • 17:51and all the time back in the 90s
  • 17:53and then projecting to 600
  • 17:54which will almost certainly occur in the century.
  • 17:58And this is the overall plant biomass for ragweed
  • 18:01of the branch per plant basis.
  • 18:04Here's the pollen production going for
  • 18:06280 to 370 double pollen production,
  • 18:09going from 370 to 600 double as you can.
  • 18:11And hey, not only was an increase in growth
  • 18:14but only increasing in terms of pollen production,
  • 18:16but also in terms of the antigen Amb a1
  • 18:19based on the ELISA test where going as an increase
  • 18:22as carbon dioxide went up as well.
  • 18:25We haven't been able to replicate this, by the way.
  • 18:27So that's another challenge for you young researchers
  • 18:30that are out there.
  • 18:31But, there's pretty good indication
  • 18:34that ragweed has this kind of respond.
  • 18:38Yeah, yeah, all the interesting doctors
  • 18:40has good interesting stuff,
  • 18:41but it's a chamber study.
  • 18:44It's a chamber study,
  • 18:45doesn't add any relevance in the real world.
  • 18:48What's wrong with you?
  • 18:50Okay, how do we get from the lab to the real world?
  • 18:53Okay, well, there's, I showed you
  • 18:57was talking about FACE, FACE free air CO2 enrichment.
  • 19:01This is the Duke University FACE which was funded
  • 19:03by the Department of Energy as we refer to it
  • 19:05in federal circles, the department that everything,
  • 19:08they had lots and lots of money.
  • 19:12So this is the rain.
  • 19:14This is pushing in carbon dioxide
  • 19:17to the low valley pine forest showed you the effect
  • 19:21of CO2 on low valley earlier.
  • 19:24This is an afterward, it turns out that
  • 19:27plants do respond differently, you know the plant that
  • 19:29responded the most with this change?
  • 19:31Within the forest understudy?
  • 19:34Of course you don't.
  • 19:36I'm sorry (mumbles)
  • 19:41There's a problem here.
  • 19:41The problem for me was this cost $5 million a year.
  • 19:45My entire discretionary budget at the time was $2, 000.
  • 19:50I could hire it for maybe five minutes,
  • 19:52but that's not really gonna work.
  • 19:55So, I kind of like,
  • 19:58how do I take it from the lab,
  • 20:01to the real world, how do I do that?
  • 20:04How do I do that?
  • 20:08Hang on a second.
  • 20:10Let's go back to the Keeling curve.
  • 20:13Why did they measure this in Hawaii?
  • 20:17I mean, I like Hawaii.
  • 20:20It's got great factories.
  • 20:22Why would you measure carbon dioxide background in Hawaii?
  • 20:27- [student] High elevation
  • 20:28and well background carbon dioxide?
  • 20:29- [Lewis] Exactly.
  • 20:31Exactly.
  • 20:32So you're measuring the background carbon dioxide,
  • 20:34you're not measuring the carbon dioxide in the room here,
  • 20:37which I chose over the camp 11.
  • 20:39Or if I go out in the street and measure carbon dioxide.
  • 20:42So that gave me an idea.
  • 20:46Yeah, so most geological, geographically isolated spot
  • 20:49on Americans have high emissions,
  • 20:50but
  • 20:53maybe we could use an urban-rural transect as a means
  • 20:58to simulate what future environment would be like.
  • 21:02If I move the temperature and a carbon dioxide transect
  • 21:06along this line from an organic farm in Western Maryland
  • 21:10to downtown Baltimore, we dug the plots and moved the soil,
  • 21:14we made the soil uniform at the same seabed
  • 21:16and so the seed was the same.
  • 21:18We monitor all this fairly carefully.
  • 21:22And I'm sorry, as an academic,
  • 21:23I gotta show you at least one slide
  • 21:25that nobody in the back row can read.
  • 21:26So this is my contribution to that.
  • 21:29And so try to go through it.
  • 21:31This is daytime CO2, early 2000s.
  • 21:35It does go up with going from rural to sub-urban.
  • 21:38Night-time temperatures go up,
  • 21:40season light goes up the number of forestry days.
  • 21:43Now there are some day time temperature,
  • 21:45now there's some concerns here.
  • 21:47One of them is ozone.
  • 21:49Well, it turns out that when you had an ozone,
  • 21:51day in downtown Baltimore, within four hours,
  • 21:54you got the same ozone occurring at the rural site.
  • 21:57So we didn't think that was too much of an issue.
  • 22:00Yeah, we did get more hydrogen deposited and rainfall
  • 22:03for the urban side relative to the rural side.
  • 22:06But the soil that we took out to each location
  • 22:09already had a great deal of nitrogen in it,
  • 22:11it was firm, so from the same source.
  • 22:14So we don't think that was too much of a problem.
  • 22:16So maybe we could use this.
  • 22:19Since there we are, two meters by two meters,
  • 22:23digging down into the soil, if you look closely,
  • 22:25you'll see Jenny Hopper (mumbles).
  • 22:28Okay, so we did that.
  • 22:30And we packed the soil, the seed bank down,
  • 22:34we took out our railroad samplers here
  • 22:37to monitor falling around each of the sites.
  • 22:40And hey, cool.
  • 22:43We got in the farm site, the rural site years
  • 22:47here's when the ragweed first showed up, the pollen first
  • 22:50showed up around day of year to sometime in September,
  • 22:54peaked and then went down.
  • 22:56Okay, now, these two lines here, these two arrows,
  • 23:01are the start of the maximum pollen based on the farm side,
  • 23:05sort of out of control.
  • 23:07And you can see it if I go to the
  • 23:08to the semi rural, the sub-urban areas starting earlier
  • 23:12and maximizing the warmer when we get to the cities.
  • 23:16Holy cow!
  • 23:18The individual ragweed plant in the city
  • 23:20with more CO2 with more temperature
  • 23:23and a longer growing seasons producing on average
  • 23:2510 times more pollen than the one out in the country.
  • 23:31Wow, okay.
  • 23:33That was a cheap way of getting a featured climate
  • 23:35to see what ragweed might do.
  • 23:38Yeah, okay, that's interesting,
  • 23:40but it's a global problem here.
  • 23:43Yeah, it's a global climate change.
  • 23:45How do we scale up from this?
  • 23:48Well, I use a very sophisticated instrument
  • 23:52on my desk called telephone.
  • 23:55And I called up different allergists and medical doctors
  • 23:58and said, "Hi, you don't know me,
  • 23:59"but I'm a plant physiologist
  • 24:00"from USK Oh, no, don't hang up, don't hang up.
  • 24:03"Hi, am a plant physio you don't know me,
  • 24:04"but would you be interested?
  • 24:05"Oh, you would, okay, great, hang on."
  • 24:09So what we did is we got allergists
  • 24:13and other pollen counters across the central part of
  • 24:15the United States to look and see whether there had been
  • 24:20a change in temperature that could be associated
  • 24:23with the change of pollen season for ragweed.
  • 24:26Now, we didn't look at ragweed numbers per se
  • 24:28in terms of the amount of pollen just whether or not
  • 24:30the season have been affected.
  • 24:33And so what we found was beginning in the 1990s.
  • 24:37And if you start down here remember
  • 24:39remember that humidity CO2 paradigm?
  • 24:43Right here, it's warm and wet.
  • 24:45We're not expecting a big change
  • 24:47in recent decades in terms of temperature,
  • 24:49but it shouldn't expand as you move northward.
  • 24:52And that's kind of what we saw.
  • 24:55That now going up into the northern part of the US
  • 24:58that from 95 to 2013 there's hardly has been a significant
  • 25:03increase in the ragweed pollen season.
  • 25:07Okay, well, we've gone from the lab, we've gone to the city,
  • 25:10we've gone to the country, lets do the world.
  • 25:14Now when I called up they said,
  • 25:15"Oh, I have a paper and PNAS, please listen to me."
  • 25:19And they would listen.
  • 25:20"So yeah soil paper that's really interesting.
  • 25:22"We wanna help you.
  • 25:23"Great."
  • 25:25Okay, so started getting data this is from Turku, Finland.
  • 25:29One of the longest pollen seasons that we had.
  • 25:31This is total seasonal pollen,
  • 25:33in terms of grains per cubic meter over time.
  • 25:38Reykjavik, Iceland, grains per cubic meter over time.
  • 25:45Kansas City, Missouri, we've since found out
  • 25:47this probably not correct because it's a long story,
  • 25:50but they got a new pollen counter,
  • 25:52it was much better in counting pollen (mumbles).
  • 25:56Geneva Switzerland.
  • 25:57Okay, you're seeing, if you're seeing,
  • 25:59I think it's fair to say a trend here, a global trend.
  • 26:03Right?
  • 26:04So basically, we went out on a lab
  • 26:07and looked at the change in pollen load,
  • 26:09the amount of pollen over the end of the season
  • 26:11as a function of different temperatures.
  • 26:13And where there was some good significant correlations here
  • 26:16in terms of, based on locations around the world.
  • 26:20But all of these locations are in the northern hemisphere.
  • 26:23So our next goal is to go to the southern hemisphere.
  • 26:27And we're working on that now, so stay tuned.
  • 26:31Alright,
  • 26:33so that rising CO2 temperatures
  • 26:36can influence pollen season falling amounts.
  • 26:39Pollen allergenicity, we're still not sure,
  • 26:42we have one laboratory data.
  • 26:44Maybe, maybe not, we need to do more work on that, right?
  • 26:48Okay.
  • 26:51Let's go to the OMG part.
  • 26:53Right, this is...
  • 26:56What's the role of carbon dioxide
  • 26:57if the trees are growing bigger and there's more water
  • 27:00available, does that affect fire frequencies?
  • 27:03I don't know.
  • 27:05Is it possible it's affecting
  • 27:06the qualitative component of the woods such as burning
  • 27:09the higher climate change or more CO2?
  • 27:13Is it affecting the air pollution pollen?
  • 27:15I don't know, nobody's said a word.
  • 27:21We talked about Kazoo earlier, well Kazoo when you give it
  • 27:23more carbon dioxide, generates
  • 27:25more volatile organic compounds.
  • 27:27Has that shifted in the last 20 years of more CO2?
  • 27:31I don't know.
  • 27:33Well, what about contact dermatitis
  • 27:35from something like poison ivy?
  • 27:36We actually know this one, I mentioned that this was
  • 27:39the one that was growing more
  • 27:40in the FACE system in the deep forest.
  • 27:43It actually produces a more virulent form of urishiol.
  • 27:46You get contact dermatitis faster
  • 27:48when you come in contact with it.
  • 27:51What about narcotics?
  • 27:53We spend billions of dollars a year
  • 27:54trying to eradicate narcotics.
  • 27:57How is CO2, how is climate affecting
  • 28:00where these narcotics are growing?
  • 28:02I don't know.
  • 28:04What about food allergies?
  • 28:07If I'm changing the quality of the composition of the food
  • 28:09is it affecting the number of food allergies?
  • 28:12I don't know.
  • 28:14Food safety, hey,
  • 28:16everybody gets sick from eating food occasionally.
  • 28:19Turns out warmer temperatures
  • 28:20can promote pathogen infestation.
  • 28:22Oh no, who knew?
  • 28:24Is climate change or rise in carbon dioxide
  • 28:26affecting food safety?
  • 28:29I don't know.
  • 28:32Funding for all of these things from the federal government
  • 28:34is, yeah.
  • 28:38Nobody's doing anything worse.
  • 28:42Here's some work we did do.
  • 28:43This is kind of thistle highly invasive species.
  • 28:46This is being sprayed with glyphosate,
  • 28:49the recommended rates under ambient CO2 that's being sprayed
  • 28:52with glyphosate under 650 parts per million CO2.
  • 28:56And added absolutely no control.
  • 28:59The reason why, is that
  • 29:01when you give them more carbon dioxide,
  • 29:02there was a difference between how much would accumulate
  • 29:05on the top and how much accumulated in the roots.
  • 29:07It did not, one of the things that glyphosate does is
  • 29:10it travels, it's systemic, it goes everywhere in the plant.
  • 29:13But if I have more roots, it was diluted out
  • 29:18and roots can generate new shoots, et cetera.
  • 29:21So what's the effect of carbon dioxide
  • 29:22and climate change on pesticide usage?
  • 29:25Pesticide ethicacy?
  • 29:28We know about this much.
  • 29:32If there is a green revolution, if there is a green new deal
  • 29:37these are the things that we need to focus on.
  • 29:42Let's work on one of these issues.
  • 29:45There's not enough time to go into all of them.
  • 29:47Let's look at nutrition.
  • 29:49And let's look at rice.
  • 29:52Rice is consumed on a daily basis by
  • 29:55about two billion people.
  • 29:58About 600 million people get more than 50%
  • 30:01of their daily food intake from rice.
  • 30:06Rice, wheat, corn, they're what we call the big three
  • 30:09that account half of the calories that you consume
  • 30:11and I would be willing to bet all my life savings
  • 30:13that you're consuming at least one of them for this lunch.
  • 30:18There's pretty good evidence that projected
  • 30:19increases in CO2 reduce proteins.
  • 30:23Some of the first work that I did back
  • 30:24at the International Rice Research Institute,
  • 30:28doing open top chamber work with different temperatures.
  • 30:31For the 94 wet season, our percent protein was about
  • 30:3510% of ambient CO2, we had a CO2 it dropped
  • 30:389.3%, the dry season similar response
  • 30:42in terms of temperature per se, reduced protein levels,
  • 30:47but it did not interact with carbon dioxide to,
  • 30:51in any kind of synergistic to reduce levels even more so
  • 30:54it was a separate effect.
  • 30:56The change in protein is ongoing.
  • 30:59We looked at future changes.
  • 31:00This is recent changes from 300 to 400 parts per million
  • 31:05for about eight different rice lines.
  • 31:07And here I think eight of the nine
  • 31:09showed a decline or significant decline
  • 31:12in protein concentration for the rice.
  • 31:15And we had to stop this because our funding got hold
  • 31:19when new administration came in.
  • 31:22It's ubiquitous, here's some work by Taub.
  • 31:25Here was in Texas and this is looking at
  • 31:28annual crop staples; barley, rice, wheat, soybean, potato.
  • 31:32This is the number of studies,
  • 31:34average and standard deviation.
  • 31:36This is the percent change in protein concentration
  • 31:39under elevated CO2 which range from about 600 to 700.
  • 31:44All of them declined with the exception of soybean.
  • 31:47Soybean is a legume, that's to say
  • 31:49it fixes its own nitrogen.
  • 31:51So when you add more CO2, it's not affected.
  • 31:54So soybean, peanut, other leguminous plants do not show
  • 31:57that change in terms of proteins with more carbon dioxide.
  • 32:04This is some work by a colleague Irakli Loladze,
  • 32:07he went through and looked at the Sweden country
  • 32:09of all the different elements in the context of rising CO2,
  • 32:13the average of about 690.
  • 32:15And what we see is that this very rapid rise
  • 32:19in carbon dioxide is causing plants to be carbon rich,
  • 32:24but nutrient poor across the board.
  • 32:28And we think there are ramifications of that.
  • 32:32So it's not just crops.
  • 32:35We're looking at at personal work that is done by me,
  • 32:38or that is done by Augustine and all,
  • 32:41came out recently looking at pasture grass
  • 32:42that have been grown under elevated CO2.
  • 32:46And what effect this had in terms of
  • 32:48weight being put on by the cattle.
  • 32:51And this is a seven year average,
  • 32:53we're looking at ambient CO2, ambient temperature;
  • 32:57ambient CO2, elevated temperature
  • 32:59and then the two bars on the right
  • 33:01are elevated carbon dioxide to different temperatures.
  • 33:0420% nitrogen which is a proxy for percent protein
  • 33:08declined significantly with more carbon dioxide.
  • 33:12The animals put on weight, took them longer to put on
  • 33:15the same amount of weight, they were slower growing.
  • 33:18So there's pretty good evidence across the board
  • 33:21that plants are responding by reducing protein levels.
  • 33:24That's going to have ramifications
  • 33:25in terms of human nutrition, direct consumption,
  • 33:28but also in terms of livestock.
  • 33:31Hey, but it's just people food, right?
  • 33:33Well, no, not necessarily.
  • 33:37We decided to look at bees.
  • 33:39And turns out that, you know,
  • 33:41bees also have nutritional requirements
  • 33:42that are important in the context of agriculture.
  • 33:46So they get their carbs from nectar.
  • 33:49Understandable, so then they do this,
  • 33:51they're really good at it.
  • 33:53They do the little waggle dance.
  • 33:54You know, the little waggle dance
  • 33:56the bee says to the other bee,
  • 33:57"Hey, you know if you go right behind this building,
  • 33:59"there's a sunflower there, 20 feet to the left
  • 34:02"of the dumpster and you'll find all the carbs you want."
  • 34:04They're really good at that.
  • 34:06They're not so good in terms of pollen yet pollen
  • 34:09is their main source of protein,
  • 34:10they get 10 essential amino acids
  • 34:12from the pollen that they consume.
  • 34:14So again, we wanted to see okay well carbon dioxide
  • 34:17is affecting protein,
  • 34:18is this in fact affecting bee nutrition?
  • 34:23And let's do it from a point of view
  • 34:24of the recent changes that occur.
  • 34:27That's a tough one to get to.
  • 34:29How did we, we chose Goldenrod because Goldenrod
  • 34:33is one of the last sources of pollen that bees see
  • 34:35in the fall before they overwinter.
  • 34:38I won't go through all the machinations we did
  • 34:40to come up with that, but it is.
  • 34:43And so it's important for bees before they overwinter
  • 34:46to have a good source of protein, and one of those good
  • 34:49source is Goldenrod so we considered it
  • 34:51to be a key for the species.
  • 34:53So what I'm trying to do is sort of two
  • 34:54lines of evidence here and I wanna give you
  • 34:56the historical evidence first.
  • 34:58And they got this through,
  • 34:59this Smithsonian Natural History Museum.
  • 35:02Now, I don't know if you've ever been to DC but it's a great
  • 35:04place to go to, you got your dinosaurs,
  • 35:06you got your elephants, you got your little diamonds,
  • 35:09it's a great place to go, right?
  • 35:11Okay, but here's the thing, way in the back in the basement,
  • 35:17right next to the Ark of the Covenant,
  • 35:19you'll find all these, okay (mumbles)
  • 35:23You'll find all these plants samples, right?
  • 35:26They go back to pre industrial times in the 1850s, 1860s.
  • 35:31And those samples included Goldenrod.
  • 35:34So we're able to actually take the pollen,
  • 35:39the stigmas, the reproductive parts,
  • 35:42and to look at the carbon, hydrogen, nitrogen ratios.
  • 35:47Nitrogen as a proxy again for protein.
  • 35:50Now, I wanna give you a second line here.
  • 35:52This is the experimental evidence.
  • 35:53This is some work that was done by my colleague,
  • 35:56a scientist down in the Temple, Texas.
  • 35:58He's since retired but this is a really cool study,
  • 36:02waiting kind of for guy.
  • 36:05Kind of circle wagons that you see here.
  • 36:08What Wayne did is, he added carbon dioxide
  • 36:11at one end of the wagon.
  • 36:12And because of photo-sensors and because it's Texas
  • 36:15where the sun's shining all the time,
  • 36:17by the time you got to the bottom wagon,
  • 36:19all that carbon dioxide have been taken out.
  • 36:21So they were looking at carbon dioxide levels
  • 36:24pre-industrial, right 283 hundred.
  • 36:28And we were very fortunate to have just enough goldenrod
  • 36:31growing along that trans sector
  • 36:32that we could actually look at the numbers.
  • 36:35So here are the data.
  • 36:37This is historical data from the Smithsonian.
  • 36:40This is the estimated protein based on
  • 36:43using nitrogen as a proxy.
  • 36:45And going from the pre-industrial time to the current time,
  • 36:49which is the beginning of the 21st century.
  • 36:52We see about a 30% drop in the nitrogen protein content
  • 36:58and an increase, corresponding increase in carbon
  • 37:00and the nitrogen of that pollen.
  • 37:02And for the experimental evidence,
  • 37:05numbers are slightly different.
  • 37:07There's a lot of the sampling so the larger the bigger,
  • 37:10but basically the same sort of response;
  • 37:13that as you increase the carbon dioxide,
  • 37:15you're decreasing the amount of protein in the pollen.
  • 37:19That has effects in terms of the health.
  • 37:24And these are already under environmental,
  • 37:26number of environmental stressors.
  • 37:28How's it affecting that?
  • 37:30We don't know.
  • 37:31We're not able to get funding to continue this work.
  • 37:34But we think it's a toe in the water stage
  • 37:36where we think it's really interesting
  • 37:37we want to do more if we can.
  • 37:40Let's go back to people food for a moment.
  • 37:43And let's look a little more deeper into rice.
  • 37:45This is work that was done two different FACE of free air
  • 37:49C02 reference systems,
  • 37:51one in Scuba Japan, which is shown here,
  • 37:53another one in near Nanjing, China.
  • 37:56And again, you're going your rice, you're
  • 37:58ejecting carbon dioxide into a field situation.
  • 38:02They did this, we did this under different cultivars,
  • 38:05rice cultivars, eight different cultivars in Japan,
  • 38:08most of the Japonica lines, some of the (mumbles) lines
  • 38:12and then also in China which had a wider range
  • 38:14in terms of indica, hybrids and so forth.
  • 38:18So the 18 different lines altogether
  • 38:20was the percent protein.
  • 38:22Again, this is, the differences now,
  • 38:24were about 550 parts per million, which is the elevated 400,
  • 38:27which is the ambient for all the lines.
  • 38:32Percent change relative to ambient CO2, again trying
  • 38:35to decline in protein for the rice.
  • 38:39You look at iron and zinc,
  • 38:41a little more scattered, but again many of the lines,
  • 38:44showing a significant
  • 38:46and rice overall showing a significant decrease.
  • 38:49Now, we wanted to delve a little bit deeper and look at it
  • 38:52in terms of the vitamin content.
  • 38:56And we didn't have this for all the different samples but
  • 38:58for the Chinese ones.
  • 39:00So B1 vitamin, B1, B2, B5 and B9.
  • 39:04And I haven't had time to go through all
  • 39:06the stats on, there's a whole,
  • 39:08there were significant effects
  • 39:10in terms of all these declining
  • 39:13as you increase the carbon dioxide, okay?
  • 39:16And then we got this out of the blue, the response,
  • 39:20it went up for alpha tocopherol, okay?
  • 39:23Vitamin E went up with more CO2.
  • 39:29So I was scratching my various body parts
  • 39:31trying to figure out what the hell is this about?
  • 39:34What's going on, okay?
  • 39:37Well, we have a working hypothesis
  • 39:40for a possibility is definitely needed, all right?
  • 39:43And here it is.
  • 39:45If you look at all the different compounds,
  • 39:48and if the compound has a lot of nitrogen in it,
  • 39:53it seems to be selected against, whereas tocopherol
  • 39:57which has no nitrogen actually showed a slight increase
  • 40:01as carbon dioxide went up.
  • 40:03The more nitrogen the compound had,
  • 40:05and this is just a ratio of the molecular weight,
  • 40:08So vitamin B9 has, 20% of the provided
  • 40:11vitamin B9 is nitrogen.
  • 40:13So it follows along pretty good curve.
  • 40:17So perking back to artemisinin.
  • 40:21Artemisinin have no nitrogen in it,
  • 40:23it went up with more carbon dioxide.
  • 40:27So now we have eight points or nine points.
  • 40:30We're still trying to figure out.
  • 40:31Is this real or not?
  • 40:33We have some recent information
  • 40:35for coffee, more coffee produces caffeine.
  • 40:37Caffeine is a bicyclic alkaloid
  • 40:39with a lot of nitrogen, right?
  • 40:41So we have some initial information suggesting
  • 40:45that caffeine is going down.
  • 40:47I know that's disappointing, right?
  • 40:49Trust me when I tell you I was very disappointed,
  • 40:51I couldn't have gone through grad school without it.
  • 40:53But it's something to keep in mind.
  • 40:56And but having said that, there was also variation
  • 40:58among the different arabica lines that we looked at.
  • 41:03All right, we tried to take all this information and say,
  • 41:08how does it affect different countries?
  • 41:10And we looked at it from the point of view of,
  • 41:14depending on the economics of the country,
  • 41:16if I'm a very poor country, I tend to consume a lot of rice.
  • 41:20For example, as China has become, as the economic status
  • 41:24of the Chinese has increased,
  • 41:26then the less rice is being consumed
  • 41:28and a more diverse diet is happening.
  • 41:30So there are usually out of the Chinese I think,
  • 41:32are the green lines here.
  • 41:33But we looked at a number of different countries.
  • 41:36And basically, the poorer the country,
  • 41:41the greater the deficit for the different
  • 41:44actually trying not to confuse myself anymore.
  • 41:48But basically, the poorer the country,
  • 41:50the greater the effect in terms of CO2 impacting nutritional
  • 41:55value of the rice that's being consumed.
  • 41:58And then we're trying to look at
  • 41:59the 10 poorest countries in the world.
  • 42:02They're mostly agrarian.
  • 42:03This was the food production in metric tons,
  • 42:06million metric tons.
  • 42:08This is the population here.
  • 42:11And then you can see food production relative
  • 42:13to population is declining.
  • 42:17This is the kilograms per person per year.
  • 42:21And we're trying to also look at
  • 42:23the elevated CO2 effect on protein.
  • 42:25This is some work I'm doing with the broccoli,
  • 42:28where he spent a sort of a an estimate
  • 42:31on the effect in terms of protein for these other staples,
  • 42:34some of the staples are, that are dominant in these
  • 42:38countries to solve the maize, potatoes, rice, sorghum
  • 42:40or sweet potatoes, but again...
  • 42:43First, sorghum used to try much but there's a lot of
  • 42:47decline in terms of protein concentration
  • 42:49for these products.
  • 42:53What else could be changing what's happening to the item,
  • 42:55of course countries we don't really know for sure.
  • 42:58Alright, so I didn't really get a chance to go into
  • 43:00all of the things in part because there's just not,
  • 43:03a lot of information out there to go into.
  • 43:06But just looking at one, the nutritional aspect,
  • 43:09you get a sense like Oh, of just how fundamental
  • 43:12an aspect this is and how important it can be.
  • 43:16So plants interact by multiple means in
  • 43:19the health of our quality, the medicine and nutrition,
  • 43:22and maybe more than just people plants with this life.
  • 43:25How is it going to affect in terms
  • 43:26of having a global impact?
  • 43:30A lot of questions to be addressed.
  • 43:32But here's the thing to keep in mind.
  • 43:35If you look at it from the point
  • 43:37of view of animals and plants,
  • 43:39and you weigh all the animals weigh all the plants
  • 43:41in terms of their biomass.
  • 43:44All animals are shown here.
  • 43:48They weigh about two gigatons.
  • 43:51Plants constitute about two gigatons of carbon.
  • 43:56All the rest is plants and
  • 43:58they constitute 450 gigatons of carbon.
  • 44:02If I affect plants, I'm going to affect
  • 44:06every living thing on earth.
  • 44:08And yet the CO2 as plant food mean dominates our thinking.
  • 44:12It's much more than that.
  • 44:16What are the consequences?
  • 44:22Where do we go from here?
  • 44:24Well, we acknowledge that there's interaction,
  • 44:28that carbon dioxide also needs to be looked at.
  • 44:31We acknowledge that the potential research
  • 44:33in the context of public health is enormous.
  • 44:36There's so much more that we can be doing with this.
  • 44:39What can we do to work together?
  • 44:45What can we do, what can we do as a means
  • 44:48to find new opportunities,
  • 44:52new ways that we can come together to try
  • 44:56and find new research to do on this area
  • 45:00that we haven't been able to find yet.
  • 45:03And I'm hoping that at some point, this will come to pass.
  • 45:09So thank you all very much for your time.
  • 45:10(students clapping)
  • 45:15- [Kai] So now is the question time and
  • 45:17if you have a question, just raise your hand ask it.
  • 45:23- [Lewis] I know it's a lot of information people.
  • 45:26Yes.
  • 45:27- [Student] I just wondered if any...
  • 45:29You know, you said that tocopherol might not go down
  • 45:32because it's not, in a way, it doesn't contain nitrogen.
  • 45:36So how's that experiment you've done when on (mumbles)
  • 45:40available - [Lewis] Yeah this is one of
  • 45:41the things that occurred to us initially was that
  • 45:44what we're seeing is because of stimulation of growth,
  • 45:46and there's a position (mumbles) of nitrogen.
  • 45:49So to counter that we made sure that
  • 45:53we had the chamber experiment where we could really vary
  • 45:56the amount of nitrogen but also ensure
  • 45:58that we're getting super amounts of nitrogen
  • 46:00something like and is one of (mumbles).
  • 46:07- [Student] Great work - [Lewis] Yes.
  • 46:08I'm sorry.
  • 46:09- [Student] No, that's great work.
  • 46:11- [Male Student] Have people looked at
  • 46:12sea grasses and aquatic plants?
  • 46:14- [Lewis] No, not to my knowledge.
  • 46:16Not to my knowledge.
  • 46:20Yes.
  • 46:21- [Student] So, as you mentioned in your view,
  • 46:25the cost is highly variable costs probably 10 hours ago.
  • 46:31They are paid by the common practices,
  • 46:33so, I guess that by, to what extent or stage
  • 46:37is impact of climate change will have observance of
  • 46:43human health outcome and also
  • 46:47using all this technology of reading,
  • 46:53nutritious varieties and also different farming practices
  • 46:57and also intensification to
  • 47:01increase productivity as a
  • 47:06to what, kind of, what can you say all these tests
  • 47:10can help us to (murmurs) and damage to the plants?
  • 47:13- [Lewis] There's a lot in there.
  • 47:15So let me try and actually to address
  • 47:17that particular number entire somehow.
  • 47:20But let me try and address it quickly.
  • 47:23One of the things that we're currently doing and nutrition
  • 47:25is currently doing justification,
  • 47:26we're using what are called monocultures.
  • 47:29The genetics of the crop that you're growing all the same.
  • 47:32So as you get rid of small landowners,
  • 47:35which have more diverse genetics, and you go
  • 47:38to bigger and bigger fields,
  • 47:41there are different reasons for it
  • 47:42that it becomes more and more uniform, has to be.
  • 47:46The problem with becoming more uniform, you don't have
  • 47:48a diversity necessary in order to find the lines
  • 47:54that are you could say different to their effects
  • 47:57and CO2 and with respect to protein.
  • 48:00That's part of our job or it was part of our job
  • 48:02when I was with USDA is to begin to look at these
  • 48:05different lines and to look at how they might respond.
  • 48:10Part of it is management and began there are different
  • 48:12aspects of that as well, because of rising water
  • 48:16product prices and water consumption.
  • 48:18Flooded rice is not as grown as much as it used to be.
  • 48:22And it has a whole nother suite of consequences that
  • 48:24I unfortunately don't have time to, we could talk more
  • 48:26about it after class if you wanna know more.
  • 48:29What we are currently doing in terms of breeding
  • 48:32is we we're seeing two dissimilar breeding attempts.
  • 48:38We have farmers and breeders who are breeding for yield
  • 48:41and breeding for taste and breeding for insect resistance.
  • 48:45And as CO2 is going up in nature, we think that in
  • 48:48itself is having a selection effect.
  • 48:50So for example, we see wild rice, weeded rice,
  • 48:54is showing a much stronger response to the change,
  • 48:57recent changes in CO2 and cultivated absence.
  • 49:01And they're actually putting more of that additional
  • 49:03carbon dioxide into seedling for the weeded rice.
  • 49:07So we think that there's an opportunity here as well.
  • 49:11And that is to look at the weeded rice as a means to begin
  • 49:14to adapt to, for the cultivated rice to adapt,
  • 49:18and to look at the both technology and genetics
  • 49:22of the weeded rice as a means to begin to bring or
  • 49:26to adapt cultivated rice, so that it can not only respond
  • 49:30to warm climate, but actually might benefit by it.
  • 49:33Okay, anybody have a cell phone?
  • 49:38Would you google something for me?
  • 49:40This isn't about... is that okay?
  • 49:43Okay.
  • 49:46Would you google to something for me?
  • 49:49Would you, and this is not about rice, but just for fun,
  • 49:52would you google carbon dioxide and marijuana
  • 49:58and tell me what the first sentence that you get.
  • 50:14What does it say?
  • 50:16- [Student] How do you use CO2 increase you
  • 50:19- [Lewis] Can you say that louder?
  • 50:20- [Student] Sure, how do you use CO2 to
  • 50:21increase yields in your marijuana.
  • 50:23- [Lewis] How do you do CO2 to increase yields
  • 50:25in your marijuana crop?
  • 50:28So I'm guessing here that if they can do that
  • 50:34and literally they have indoor chambers and they're doing
  • 50:36it you know that way.
  • 50:38But remember the CO2 has already gone up by 30%.
  • 50:40Are we missing out on an opportunity by not taking
  • 50:44the increase that's already occurred and begin
  • 50:46to find the best suited genotypes that can take
  • 50:49that increase and divert them into seeds.
  • 50:52I can go online, I can do this in more depth,
  • 50:55I can find out from the marijuana industry,
  • 50:58when to give the CO2, how much to give the CO2,
  • 51:01what the temperature is to give the CO2,
  • 51:02what the hormone THC I can get from the CO2 will be.
  • 51:07Why can't we do that for food?
  • 51:10I would argue there's an opportunity there.
  • 51:13Anyway
  • 51:16So...
  • 51:17Yes.
  • 51:18- [Student] How's it that when kind of follow the
  • 51:20mass cyber, there isn't any much of a research into
  • 51:24trying to (mumbles) the decrease in vitamins
  • 51:28and minerals in the plants and
  • 51:29to actual public health in the past?
  • 51:31- [Lewis] No, and that's a good point.
  • 51:33We haven't done that yet but,
  • 51:36that's one of the things we'd like to work on.
  • 51:40We put in a convergence
  • 51:44RFP for NSF to do that.
  • 51:47And they turned us down.
  • 51:48So we, I know,
  • 51:52we're still on track.
  • 51:54I think it's important.
  • 51:55Yes.
  • 51:56- [Student] Yeah, on that note, I mean,
  • 51:57I couldn't help but wonder in your, during your presentation
  • 52:01if the increase or if the alarming increase in
  • 52:10malnourished, obese folks might have, you know, if
  • 52:16I'm sorry, can't talk to the, I just gave up coffee
  • 52:19- [Lewis] Oh, am sorry.
  • 52:20(laughing)
  • 52:24- [Student] You spoke about plants being carbon rich
  • 52:29and vitamin poor, now right?
  • 52:31And so I can't help but wonder if
  • 52:34that could potentially be some contributing factor
  • 52:38to this concurrent prevalence
  • 52:42of obesity alongside malnutrition.
  • 52:45- [Lewis] We don't know, we think it could be,
  • 52:47certainly logically interpreted there's...
  • 52:50it could be, but we'd like to be able to get
  • 52:52the numbers just to show it.
  • 52:53- [Student] Sure.
  • 52:55- [Lewis] So unfortunately, that at the moment,
  • 52:58it's the Chinese folks, we just have to ignore it.
  • 53:02- [Student] I also had another thought and maybe it's
  • 53:05for everyone in the room,
  • 53:06just from a public health stand-point,
  • 53:09you know, are there...
  • 53:10do we know of any large ongoing sources of data
  • 53:14that actually, that ask about allergy, food allergy
  • 53:19or environmental allergy?
  • 53:21But this isn't my area of research,
  • 53:24but does anyone know of any?
  • 53:27- I don't imagine that there are databases
  • 53:30for food allergies that are available.
  • 53:34I don't know how far back they go.
  • 53:38And it would be difficult thing given the other issue
  • 53:41in epidemiology is early exposure, and other aspects
  • 53:45that make it difficult to try and assess with
  • 53:47a separate role of climate of carbon dioxide.
  • 53:51But it's a good idea.
  • 53:53We did, I didn't mention this, but we did a study on peanut,
  • 53:58we have two different varieties of peanut
  • 54:01which we grew at different carbon dioxide concentrations,
  • 54:03and over a two year period, and one of the varieties
  • 54:08for both years showed an increase in Arachis stage one.
  • 54:11Arachis is peanut genus that's also the name
  • 54:14of the primary allergen that peanuts produce.
  • 54:17It's about a 10% increase in the allergen,
  • 54:18but the other one didn't do anything.
  • 54:22So it needs more work.
  • 54:24We need to find out why is this line responding
  • 54:27the other line not responding.
  • 54:29What's going on?
  • 54:31We just don't know.
  • 54:34Yes.
  • 54:35- [Student] I have kind an answer to your question.
  • 54:37I mean, those collect technology
  • 54:41so they have some (mumbles) from 2007, 2010.
  • 54:47Probably just some recorded geology.
  • 54:51And it looks like they have problem (mumbling)
  • 54:54the categories so...
  • 54:55- [Female Student] Oh, awesome, thank you.
  • 54:59- [Lewis] Okay, yes, last question.
  • 55:01- [Male Student] That is (mumbling) though is that
  • 55:07the total climate change mitigation challenges
  • 55:12that mattered, is there any one focusing on
  • 55:14the technology challenges (mumbles)?
  • 55:18- [Lewis] There are a number of things, for means better
  • 55:20at the management level, but also at the genetics level
  • 55:26and at the consumer level and we think,
  • 55:28within the food system are ways to reduce
  • 55:32greenhouse gas emissions.
  • 55:34So for example, one of the things that USDA was working on
  • 55:39before I left was
  • 55:41was called
  • 55:44water deficit irrigation with rice.
  • 55:47Typically, rice is flooded because
  • 55:50it's a way of keeping weeds down.
  • 55:53And, but flooding rice also produces a lot of methane.
  • 55:57And so if you change the management, you can reduce
  • 56:00the amount of methane that's being produced.
  • 56:01But farmers are worried and of course,
  • 56:04they do that, that's going to reduce
  • 56:05the bottom line of production.
  • 56:08So USDA was doing studies trying to look
  • 56:10at alternative drawing and say that they did management plan
  • 56:15as a means to see if it would reduce methane.
  • 56:17Because you can't wag your finger at a farmer
  • 56:20and say you're producing too much methane.
  • 56:22But you can go up to them and say, "Hey, you know
  • 56:23"I've go this great idea that's gonna increase your yields,
  • 56:26"but also reduce your cost for water,
  • 56:28"oh by the way, it's gonna reduce the methane,
  • 56:29"but you don't care."
  • 56:32And just go, go with that.
  • 56:34There's lots of opportunities.
  • 56:37What if you were a pure consumer, and you're at the market,
  • 56:40and you're looking at buying a package of beef,
  • 56:44what if the information was there,
  • 56:46it says how much of my greenhouse gas feature
  • 56:49for buying this kind of be for us?
  • 56:51Yeah, you know, I could compare it to different brands
  • 56:54to see, okay, well, I've got three different brands
  • 56:56of beef here, but hey, this one's producing much less
  • 56:59greenhouse gas, maybe I should buy this brand.
  • 57:02So yeah, there's lots of really cool, interesting,
  • 57:06fun things to look at.
  • 57:08I mean, it's just, it's a question
  • 57:10of having the resources to do it.
  • 57:15- [Kai] Okay, thank you for this kind,
  • 57:18I think it was an excellent lecture.
  • 57:21Although we have a few, many but all of us have an interest.