BRAD NEWBOLD 0:01
Hello everybody and welcome to we measure the world, a podcast produced by scientists for scientists.
MARCO BITTELLI 0:08
Even if tomorrow morning, we stopped burning fossil fuels, which is unthinkable, you know, from tomorrow morning. And there's not a single molecule of co2 from fossil fuels going into the atmosphere, the climate will not reverse quickly, because we are at over 400 ppm in volume in the atmosphere. So in any case, we're gonna have to adapt and mitigate what we already did so far. So understanding the water budget, the soil water budget plant, you know, plant dynamics, cropping systems, it's key. I mean, we also we are going to be between nine and 10 billion people, they estimate, you know, if you look at FAO, they have a certain number, the United Nation is another number. But the estimation is laid by 2050 will be probably about 9 billion people, if not more on the planet. You know, so we need to feed the 9 billion people in this in the changing climate. These are challenging topics.
BRAD NEWBOLD 1:09
That's a small taste of what we have in store for you today. We measure the world explores interesting Environmental Research trends, solutions to research issues, and tools to better understand the entire soil plant atmospheric continuum. stay current on applied environmental research, measurement methods and more. Thanks for joining us.
HOLLY LANE 1:29
Today's guest is a soil physics expert Dr. Marco Bittelli. Marco received his bachelor's degree in agricultural sciences from the University of bolonia in Italy, and his Master's and PhD in soil physics from Washington State University in Pullman. He spent a year as a postdoc in the physics department at the University of Heidelberg and now teaches courses in soil physics, hydrological modeling, philosophy of science and scientific methods at the University of bolonia. Marco is a referee for the National Science Foundation and also serves as a reviewer for international journals. He is the author of two books and the co author of multiple book chapters, journal papers and has over 70 papers and conference proceedings. And to top that off, he is also signed jazz guitarist and has released three albums. Marco, thanks so much for being here. I'm really excited to talk with you. Can you start off by telling us how you got into your field? And also how you got into jazz guitar?
MARCO BITTELLI 2:29
Oh, yeah. Okay. Well, when I was a teenager, my mother took me into a trip to Egypt. My mother was a professor of mathematics. And when she retired, she became a travel guide, because she loved to travel the world. And so she went all over the planet. And she took me to Egypt, and I remember in Tabor, which is this beautiful ancient city on the Nile River, we dove into the desert. And there was this Botanical Garden, within a greenhouse, very big, kept by a British man. And he was established by the British government a couple of centuries before. And it was just unbelievable to see that, of course, there was water there, but there was a deep well, so in the middle of the desert, there was this incredible botanical garden with an enormous variety of species. And so I came back from that trip, deciding to study plants and soil and the environment. So I finished high school and then I enrolled at the University of Bologna in the Department of Agriculture. And that's where, really the initial motivation then along the way, originally, I wanted to study topical crops because of that very trip, but then along the way, I met this wonderful professor, Professor Luigi kvass, have actually recently passed away. He was teaching soil and environmental physics. And when I took his class, I found that that was the subject I wanted to, to study. And so that's the motivation for science. For guitar, my brother is a professional musician and composer. He actually wrote songs with Vasco Rossi. I don't know if there is any Italian listening to this podcast, but if there are Italians listening, Vasco Rossi is our biggest pop star in Italy, you know, really, number one. So he's older than me. My brother is six years older than me. And so he gave me a guitar when I was 12. And then, the love of music has been running in the family. My grandfather was a musician. So he's been always running in our family. But he didn't make it a career. I decided to just yeah, it's just it's just a passion. Yes.
BRAD NEWBOLD 5:01
Yeah, so we're super excited to have you so we can kind of have this discussion of some of your more recent projects that you've been a part of?
MARCO BITTELLI 5:09
the largest project is in Antarctica. So Italian friends friends have an expierimental station is called Concordia. This is an important station that has been going for a long time. In the summer, there are up to 200 scientists who work in that station, they do research in a variety of areas related to ice and Antarctica and climate. Our project is dedicated to the measurement of the electrical properties of the Antarctic sheet, basically, the reason is because the thickness of the sheet is determined by by a variety of methods that are measured based on gravity. They measure based on GPS. But an important method is by satellites, with radar and microwaves, satellites that are sending signals. If they are active satellites, if they are passive, they're just receiving the signal and the time the signal takes to cross the ice. Help us to understand the sickness of the ice.
HOLLY LANE 6:24
So when you say the sheet, you're talking about the ice cover,
MARCO BITTELLI 6:28
yes. So under Antarctica, we have darkened and it's very thick, it's a very thick amount of ice. And then we need to know how much ice we are losing if we are losing any, and we know we are losing it right being some debate for a few years. But now we know. Unfortunately, we are losing a large amount of ice in Antarctica as well. So we need to quantify and understanding the policies related to climate change. I, together with many 1000s, of other scientists believe this is the most serious issue we are facing as human species this century. It is an incredibly serious problem. We started also in the Alps, I will get to that topic later. But what what our project is is dedicated to is to collect ice cores measure the dielectric properties of ice cores to be able to improve our models for the satellites. We already published the paper recently in cold regions science and technology in which we are showing the data and we developed a model that allows it to have this information for remote sensing.
HOLLY LANE 7:40
So some of that work, then is ground truthing.
MARCO BITTELLI 7:43
Yes, is mostly done in situ. So we go there, and we collect ice cores. And we also bring the ice cores back to Florence. So they go on boats, and they go all over the planet
HOLLY LANE 7:55
Do you keep them frozen?
MARCO BITTELLI 7:56
Yeah, of course, we need to keep them at the same temperature at which they are collected. And, and then when they arrive in Florence in our cold room laboratory, we measure additional properties, mostly chemical properties, that we have more difficulty measuring in situ, because there are some ions that are present in the eyes that affects the dielectric properties, in particular, the imaginary part. And then we do a lot of modeling. Clearly after having collected the data. We have this the electric models, the electromagnetic models, so to to characterize the eyes, the eyes. So that's been my most important in terms of time and money and involvement. And we also study ice in the Alps. This is a very recent project that I'm going to start in September. And again is to try to characterize is no melting and ice melting. Because also our glaciers in the Italian Alps are losing a large amount of ice and snow, right every year. And so this is very serious because the entire population of Italy, I mean is affected the water budget on an area where millions and millions of people is determined by the recharges of groundwater and reverse. So both surface and underground water because of snow melting. So instead of having snow slowly melting into the soil and recharging the groundwater, we have just precipitation as rain is a completely different ballgame in terms of the water budget. And so this will affect the availability of water for agriculture and for Cities.
HOLLY LANE 9:55
Does that affect water quality as well?
MARCO BITTELLI 9:57
Yeah, certainly. Certainly. Because you haven't runoff with the rain as a movement of sediments and, and pollutants. So nutrient so is very different, right? I mean, there's a water budget driven by snow melt or driven by marine
HOLLY LANE 10:18
glacial runoff play into something like that, compared to like a glacier melting versus active new snowfall or precipitation.
MARCO BITTELLI 10:27
Well, glaciers formed because of accumulation of snow that under a certain temperature level, you know, below zero, over the over the geological years of use over a long period of time became a permanent glacier. So when you have a decrease in snow melting, you're not accumulating news now into the glacier. And if you have higher temperature, you're melting. There is, I mean, there are so many images and pictures. But I was last year, I also like to climb the mountain. So as as one of my probably myself to bash, I like to climb a mountain. So last year, I went to the summit of the marmolada, which is the only glacier we have in the in the Dolomites. And that there was a hole that they made. I think it was a 1895 the hole was made in there rock, to be able to hide into the rock from the glacier. So they were walking from the glacier into this hole into this cave. Now that cave is 95 meters above the current level of the glacier, it means that from approximately let's see 1890 so 100 and 30 years ago, or something like that, we lost the thickness of about 90 meters of of glacia. When you see that its BANG its right in your face, you realized how much ice we are losing. And there was a paper. You know, the EU, the European Geophysical Union that we have in Veen every year that there was a paper that estimated that, that by the end of this century, all the glaciers in the ARBs will probably be gone. Now, of course, I hope that paper was wrong. But if we don't change direction, is going to be probably incredibly problematic issue. Most of my research now is directly or indirectly related to this even another problem we have is to study landslides and the water budget in vineyards, in Italy or in different agricultural settings. But that also related to climate change, because in Italy, when I was a student in the College of Agriculture, we knew that we did not irrigate grape vines for wine or for eating grapes, it was not an irrigated crop. Today, it is an irrigated crop, meaning that many farmers realize that if they don't have a debate navigation system, some seasons, because of the lack of water of the high temperature, they cannot get enough yield, or the wine quality is very bad, or if there is too much sugar, then for too much alcohol. So it became an irrigated crop. Now in Italy, even in the north, you know, between when I was a student now I'm 54, so in over 30 years, so croping system of changing and this way, I think the devices you develop at Meter, we use them all the time, because we really like your devices they are very reliable, but they are very important, they will be more and more important because we need to monitor and at this point, we cannot really completely reverse it. And even if tomorrow morning, we stopped burning fossil fuels, which is unthinkable, you know, from tomorrow morning, there's not a single molecule of co2 from fossil fuels going into the atmosphere, the climate will not reverse quickly, because we reach already over 400 ppm in volume in the atmosphere. So in any case, we're gonna have to adapt and mitigate what we already did so far. So understanding the water budget, the soil water budget, plant, you know, plant dynamics, cropping systems is key. I mean, we also we are going to be between 9 and 10 billion people, they estimate, you know, if you look at FAO, they have a certain number, the United Nations has another number, but the estimation is led by 2050 will be probably around 9 billion people, if not more on the planet. You know, so we need to feed the 9 billion people in this in a changing climate. These are challenging topics
BRAD NEWBOLD 15:08
With your discussion and interest in climate change and how it's affecting agriculture and other aspects of our daily lives. Does this play into your projects as well? You've worked on some projects with levees in the PO river or in shallow landslides and those kinds of things. Are those related..?
MARCO BITTELLI 15:26
Sure sure yeah, I mean, it's not only related to climate change, floods existed before there were floods 300 years ago, but probably with changing precipitation patterns and the frequency of certain extreme events these will become even more initial so the protection of river Levy's indeed and and landslides outdo even your by the fact that the material saturates you know, soil saturates and then you reach a certain threshold for the mechanical properties and then the landslides can occur, you know, you There is, of course, quite a bit of physics and mathematics behind it, but but really the water, I like to say water potential better than water content, because really the variable we need to know, to understand the process of landslides is the water potential.
HOLLY LANE 16:22
For those listening who maybe aren't familiar with the term water potential, can you describe how that compares to just basic water content?
MARCO BITTELLI 16:31
Sure, water potential is the energy state of water in a system with respect to a level with a reference level that we are assigned to have zero water potential. So if we imagine to take a bucket of water, we put it on this table. So from the gravitational standpoint, we can decided that this table is at level zero. But commonly, we choose the ground surface as our level zero. So if I move this bucket of water up or down, I change its gravitational potential. Now, if this water is completely free of ions, so is pure water, there is no forces exerted on this water by the fact that there are bindings with the ions. So that's water potential is zero. Now if I take this water, and I put it into a vase with soil, then the water is binded by capillary forces and absorptive forces on the surface of the soil. So in that case, this the water is not free to move, as it was before. So that's called the metric potential. So the water potential is basically the energy state of water in a given system, it can be a soil, it can be a plant, it can be a food, you know, it can be a cracker or a piece of bread. So with respect to a reference level, and so the energy state, that means the water movement and the rate of water moment, for instance, within the soil, so water moves in the soil, because there is a difference in water potential. So its the difference in the in the energy state.
HOLLY LANE 18:14
So that's why it's much more informative than just knowing how much water is there, because it tells you something about the energy state of the water and where that water might go.
MARCO BITTELLI 18:23
Yes, absolutely. Yes. Clearly, the two properties are related with what is called the water retention curve that puts you in relation the metric potential and the water content. But really, what's the driving force for movement? It's the potential. Even in the vapor phase, I mean, water moves from the soil through the plants toward the atmosphere, because there is a gradient in energy. This applies also to water vapor.
HOLLY LANE 18:53
So I know that you've done a little bit of work, but looking at the best way to actually measure and understand matrix potential. And you've compared pressure plates and other methods. Can you talk a little bit about that work?
MARCO BITTELLI 19:05
Yes, pressure plate, is a classic technique that I think it was developed by Richards was a very famous scientist in our field. That's why they have called Richards play. So I guess that's why he developed those. And the way they work, basically, you put a sample into into a container, then you apply an external pressure, for instance, with a compressor, and then when you think that you reach a certain equilibrium, let's say at one bar, then you see when water stop dripping out from that container, it means that the water is at equilibrium with that pressure. And then you take out the sample, and you measure how much water there is in that sample. And so you create a relationship between a value of metric potential and the value of water content. By repeating these measurements a different pressure you develop your water retention curve,
HOLLY LANE 20:06
because every different type of soil has a different relationship.
MARCO BITTELLI 20:10
Yes, yes, sandy soil has a different water potential with respect to a clay soils or silty loam, and so forth. But also you have a different level of water content, a different level of water potential, the lower the water potential, so the more negative the less amount of water you have. So that sometime is as fast as an absolute value, but if you think it is a minus sign, so the amount of energy that you need to apply to bring it back to zero, then the drier the soil, the lower is the is a level so, but we found out already, I think the first paper was over 10 years ago, that when the soil was gets very dry, the soil does not really reach equilibrium. Even if you leave it in the plate for many, many days or even months. The reason is that the hydraulic conductivity becomes so small, when the soil is so dry, it's very difficult for the sample to reach equilibrium and to be able to really identify the exact value of water potential with respect to the water content that you have in there. So in practice, you don't see the water that should come out at that level of water potential because the conductivity is too small. So that technique may provide some wrong data below. I think it was about 50 Joule Per Kilograms, we found out that Yeah, so it's 50 kilo Pascal, which becomes...
HOLLY LANE 21:46
Which for people who aren't familiar with that scale. That's right, in that plant available range for water. Right?
MARCO BITTELLI 21:53
A little bit below a little bit because usually plant available water. Yeah, I know it is because we now know it is right there is no plant available water is between field capacity, which is minus 30, let's say for refined soil to what they call wilting point, which I think is another number that doesn't have much sense to me, wilting point, and they will tell you why later. But yeah, the plant available water is in that range. So it's in the upper part of the plant available water, the soil is still fairly wet at 50 joules per kilogram. So I think there are many wrong data in in databases. And, and then we found out that using dewpoint methods, for instance, methods based on equilibrium of the vapor phase provides way more accurate value in that dry part. They say in, you know, in the dead dry, but below that value. So we first published a couple of papers showing the a mi, and not the reliability of these methods, and then we compare it with other methods that are more reliable. There is techniques in our field that, in my opinion needed to be abandoned. Yes, that's the way in every field, you know, I mean, in medicine and engineering, I mean, you use a technique for a century or two, that pressure plates is not at all, I think that from the 40s, but I think it's time to change, we have better techniques,
HOLLY LANE 23:25
what are the techniques that you choose to use that you think are the best options?
MARCO BITTELLI 23:29
Well, for water retention, I really like the HYPROP by Meter is an evaporation methods that provides the water retention curve, what I like about it is that it also provides the hydraulic conductivity, because it's based on inverse methods, we compute the hydraulic properties from from fluxes and known water potential, because you have two TENSIOMETERS. So, you know the value of the water potential in two points. So, I use that technique I still use vapor pressure methods for in the lab more and more in recent years, I like to get the water retention directly in the field. And because also you see phenomena like hysteresis and that you could do it also in the lab, but not really because the evaporation methods you know is a drying methods. So, you just dry the soil and so, you see all the the dying part of the curve. While in the field also is a little bit more complicated to analyze the data, you see the different branches of ice theories. And so I usually place a water content and a water potential measurement right there in the field.
HOLLY LANE 24:47
Because then you can see the dynamics of rainfall. And, evaporation.
MARCO BITTELLI 24:52
Exactly, exactly I see the dynamics directly in the field, they can build a water retention because clearly they can take the value of water potential and water contents at the same time. Yeah, this what they do more and more.
BRAD NEWBOLD 25:05
So earlier you touched on working with river embankments on the PO river and also talking about those shallow landslides. Is that primarily using water potential? Are there other measurements that you're using for those projects?
MARCO BITTELLI 25:17
Well, there are there are a series of measurement that geotechnical engineers do. So mechanical properties. So resistance and friction angle, I want to say I'm not an expert in soil mechanics. So I work with geotechnical engineers, and they take care of that part. You can't do everything at least for me, I couldn't, I couldn't do everything. So it's an area of soil physics, that is I'm probably not the most expert in it. So, but we work together well. So they I work with the geotechnical engineers who take care of soil mechanics, I take care of the hydrological measurements modeling of soil water movement, and the the water budget you know, so the contribution of plants and so forth. So they make a series of measurements for mechanical properties. And they make the measure for data logical properties. In terms of hydrological properties, yes, we measure water content, water potential, hydraulic conductivity is very important. They call it permeability. They geotechnical engineers cause the water potential suction, I've been trying to convince them to change name, because it's in physics, it is a physical properties and this energy state, but they keep calling it suction, which is fine. I'm just joking. So we measure suction, and we measure water potential and the water budget.
BRAD NEWBOLD 26:51
And so with in in working with those those various measurements, and especially if you're dealing with slope stability, or embankment stability or other things like that, are there any difficulties that you run across in making those measurements or at least trying to interpret the data that you're coming across
MARCO BITTELLI 27:07
what the first difficulty we encounter was to reach depth that we usually don't reach in agriculture, because the levees are very deep, you know, so we built a an instrument that I think meter then patented is now selling it, I have to say what the idea was of Paolo Castiglioni just for reference, basically, it is an installation device that allows to install the sensors we, we went down to eight meters, if I remember correctly, but the paper is published. So the idea was okay, we can of course, you cannot dig a trench in river. If it goes down, right, so the problem is to Don't be invasive. And while in agricultural, the root zone, you know, when you go down to one meter, two meters, you're happy. And also often in agriculture, you can dig a trench without making much damage to your field in those condition, you cannot do it. And so we drill the borehole. And then we develop this device that is able to push the sensor inside. And there is also a little camera. So we could see if the sensor was properly installed into the soil. And that was very neat. I like it, because we could get information really quite deep in the profile. Yes.
BRAD NEWBOLD 28:32
We've had a lot of a lot of folks who have really enjoyed using the borehole installation tool. Yes, it is much less invasive,
HOLLY LANE 28:40
Much less labor to you dont have to dig so much.
MARCO BITTELLI 28:42
Yeah. And it is yeah, it's so expensive also, because, you know, if you have to dig a trench, you have to get a specific machine. There's quite some money. So, so that was a we work together. I mean, we did our contribution. But I think the mechanical part really was Paolo came out with that idea of putting the leverage. That worked. Well, that was one challenge. The other challenge that we're facing today is spatial value. I mean, not today, it's been known for decades is that is that even across the river, the properties changes so much, especially in Italy, that is a very old country. I mean, those levees were developed over centuries. And so who knows what they used at the time, of course, you can probe and collect sample and understand what material they use, but they are very variable. So that's another issue we need to work on, on methods that get information on the spatial variability. That's why I've been working on GPR so geophysical methods now I'm working. But I've been just using a methodology that is developed by Professor Mantovani Fella who's developed a gamma ray. Plot proximal spectroscopy with gamma ray that allows To get information on water content over a larger area, so again, it is his field is working on it is I don't have a gamma ray in my lab, I don't work on it, but I started to use it. And I found it very promising as methods. So the next challenge for us is to try to incorporate in our models, these natural spatial, natural or human made spatial variability, both in natural conditions or in manmade structures,
HOLLY LANE 30:38
you've kind of been talking a bit about climate change, and we've reached this point of no return in a way. And so how do you keep from getting really discouraged and deal with maybe some of those negative emotions that your research brings up?
MARCO BITTELLI 30:51
Well, I have faith in humans. So I think we will overcome this, you we will pay a price. So we are already paying a price for what we did to the planet, but it was part of our evolution. So, you know, I am not that kind of person who think we will go back to, you know, using horses to move around. So fossil fuels was a part of our history, we found out that we could use that energy to improve, you know, to have better lives. I mean, if you think of the lifespan of humans, like 200 years ago, when Mozart was alive, I think the average, you know, length of a lifetime was about 40 years now now is about 80. And so we improved, we improved on many, many aspects on the human rights on technology society. So fossil fuels were a chapter of our history as humans, we need to move into a different chapter. And they think we have the capabilities to do it, we need to build the awareness. This is a global problem. It is an issue that involves all of us, from everywhere, China, Europe, India, Australia, Russia, the entire planet, is involved. Because these are processes that are not limited. Now you're having a lot of fires here in the northwest, you know, and then then in other areas of floods, we need to think globally, like an astronaut will do. You know, if you've seen those astronauts to stay in the International Space Station they look at at Earth, and they see it as one thing, you know, they see it and our mother earth, that's what we should do, we should think more globally, be less selfish. So think about the planet as one thing, and then I think we'll we'll be able to overcome this problem. And we will have learned because all the sciences that we are doing now will be science that will be with us. And I have two children. So I like to leave them a planet that is still livable, I definitely feel emotional. As I said, I love the mountains, because my father loved the mountain himself. I was I was 16, 15 when he took me to those peaks in the Alps. And so now when I go back, seeing the landscape changing so much, it is emotional to me I see the impact that we have on the planet. But for me, it's a motivation. And I tell the same to my children because it's something we all have to do with it. We have democracies, we can vote, we can buy an electric car, we can install solar panels. So on our roofs, we can use less water, we can eat differently. There are a long list of things that as individual we can already do. I took a cab coming back from the Alps, going back to Bologna in my last field trip and the taxi driver, had an electric car. So I spent the entire time interviewing him. I learned a lot of great stuff, you know, he has a charging station in his garage at night at which he has a fixed price of 120 euros a month. And regardless how much energy though so is is much less expensive than gas for him. He goes to sleep with one charger, he does 450 kilometers. So I think is about 300 miles. So it's perfectly enough for his work as a taxi driver. And, and so it works. Obviously that energy must be produced without burning fossil fuels. Otherwise, it doesn't make much sense, but we have the technology to do it. So long answer for short question, but yes, I do get the emotional, but I'm optimistic I don't think we will extinct you know, some time you read the extinction of the human species, stuff like that I don't believe that we will have to adapt to a different climate. But we'll, we'll be able to do it right.
HOLLY LANE 35:15
And the more you learn about climate change, the more we know about how to mitigate it and make improvements.
MARCO BITTELLI 35:22
Yeah, we need to understand it to how to mitigate it. Think about Venice, about even Miami, there are cities where they are already building structures to contain the water, because of the rising sea level. And these are big projects, you know, they're not small things. So we need to be able to quantify these changes in an accurate way.
BRAD NEWBOLD 35:44
I think that one of the difficulties is that a lot of times it's human nature to be very myopic, and self centered and not proactive, because they don't really see the effects that it has on them right now.
MARCO BITTELLI 35:57
BRAD NEWBOLD 35:57
Or in the future,
MARCO BITTELLI 35:58
you got the right point and allow me this comparison. Look at COVID, COVID, has been a very serious thing. So I don't want to be misunderstood. You know, I understand it. Today we about 4 million people died globally of COVID. So it's not it's not a joke. So I first I want to make this clear that if we reacted to climate change, and for the seriousness of the topic, the same way with reacted to COVID, we could do an enormous amount of thing. The reason is, that is easy for me. And for you to understand the risk of ending up in an hospital, with tubes in your nose to breathe is a very palpable, immediate fear. And with that fear, we stopped the world, you remember the images of New York, Rome and Paris completely empty is out of a movie, we were able to stop the planet flights with people will not flying because of a virus that killed 4 million people. And the reason is that it was easy to convince people of this threat. Now climate changes, if we don't act will be more way more serious than COVID by orders of magnitude more serious than COVID. But the reason we cannot convince people to act as strongly is because it's a challenge that we don't really perceive. And so the problem with climate change is it's as you said, use exactly nailed the point here. I mean, you got it. We need to make people understand about the seriousness of this issue, even if they don't perceive it immediately as a risk for their health. And we have the power to do it.
HOLLY LANE 37:37
Are you working on any current music projects?
MARCO BITTELLI 37:41
Yeah, I'm recording my fourth album. Okay. fourth album. Yes, yes. So I think I will have a new album next year.
BRAD NEWBOLD 37:49
Oh, that's great. That's great. Well, yeah. Well,
HOLLY LANE 37:52
I think our time is up. So thank you so much, again, Dr. Batali, for taking the time today to talk with us about your research and music and life advice and all that fun stuff?
MARCO BITTELLI 38:03
Well, I want to add something because I know this podcast is made here at Meter. And I really, I really enjoyed working with people here. And I've been working with them for a long time now. And it's really good, beautiful to collaborate, very open minded people, great serious scientists to Gaylon Campbell who was my major professor, and then all the people here calling and all the family. So yeah, I've been lucky to meet such smart and generous and good people. So I am happy to be here today to speak.
BRAD NEWBOLD 38:43
We were grateful that you were able to stop by absolutely with us. We appreciate Yeah, your your insight. And yeah, all the work that you've been doing.
HOLLY LANE 38:53
And if you listeners have any questions about this topic for us, or for Dr. Bittelli, you can always feel free to contact us at metergroup.com or you can send us a Tweet @meter_env or you can reach out to me at HLplants. And you can also view the full transcript from today in the podcast description.
BRAD NEWBOLD 39:13
That's all for now. Stay safe, and we'll catch you next time on "We Measure the World."