Climate, C02, Plants and Public Health:Ignorance is not bliss
March 05, 2020Lewis H. Ziska, PhD, EHS, Mailman School of Public Health, Columbia University.
Sponsored by the Yale Center on Climate Change and Health
Information
- ID
- 4912
- To Cite
- DCA Citation Guide
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- 02:19So, if you look at, this is a little bit out of date,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.