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

March 05, 2020

Information

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

Sponsored by the Yale Center on Climate Change and Health

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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02:19So, if you look at, this is a little bit out of date,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.