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Climate Leadership Legacy: Interviews with Dr. David Hollinger

Listen to a short collection of recorded conversations with Dr. David Hollinger on becoming and being a research scientist, starting a climate hub, and the importance of climate optimism through it all.

Dr. David Hollinger has led the USDA Northeast Climate Hub from its inception in 2014. In parallel to his director role at the USDA Climate Hubs, he was also a career scientist with the US Forest Service’s Northern Research Station based in Durham, NH. As a Plant Physiologist, Dave studied how the environment effects plants, and in particular, trees. He has led long-term research into impacts of climate on forest growth and water-use at the Howland forest in Maine, and helped found the AmeriFlux network of research sites. Much of his recent research interests have included cost-effective and practical responses to changing climatic conditions in forests and on farms across the northeastern United States.

Part 1: On Becoming and Being a Research Scientist

Recorded on December 8, 2022

I think I decided or realized in college that I didn't really want a desk job, although in the sense that's what I ended up with. I was lucky, I guess. I met some professors that, you know, were very inspiring to me. You know, both I had a couple in high school that way. Also in college. And then once I graduated from college, I had a actually before I graduated from college, I worked as a field assistant for a professor that did sort of ecological research. And that was, that was great. I mean, spending a summer sort of getting paid to sort of, you know, hike in the mountains and you know, dig up soil samples and bring them back. That was a that was a pretty good deal. So I decided I'd try to try to continue , continue on in that direction. We used to consider when I was a graduate student that carbon dioxide, the ambient levels outside were about 340 or 350 parts per million. And in fact my advisor thought that they were sort of 330 or parts per million because when he was a student that's, that's what they were. And actually by the time I think I finished grad school, it was maybe 360 parts per million. And through my career and the work that I've been doing up in, up at this Howland research forest where we've been measuring the forest carbon cycle, one of the things we do is we measure the CO2 concentration - continuously. And you know, there is an annual cycle where it goes, it's a little higher in the wintertime, in the summer time, there's so much photosynthesis occurring in the biosphere that the the whole atmospheric levels drop by, you know, ten or 15 parts per million. But, you know, I was looking at the results just the other day. It's about 420 parts per million right now. So so that's a huge increase in just in my working career, not even in my life. You know, it's probably 60 parts per million and it's gone up and it's which is about right because it's been roughly two parts per million a year. So there you go. In recent times. So that's, it's easy to measure. There's no, there's no controversy that it's going up. You can measure it everywhere. The atmosphere is so well-mixed. And just as a you know, course, as, you know, just part of my work, I see that going up all the, all the time. And that's just there in the background, going up and up and up. I grew up in eastern Massachusetts and back in the, in the, in the sixties, and the seventies and early seventies, I guess. And I remember we used to play pond hockey in the wintertime, and that was a sport that we played between Thanksgiving and Christmas. And, you know, I don’t think, the ponds don’t even freeze anymore at that time of year. Where, you know, it's, here we are in, we're in, you know, the Seacoast of New Hampshire, and it's pretty similar climate to, you know, down there in Massachusetts. And I don't know, it's just another 50 degree day today or something. So it's it's certainly changed. You know, as a researcher, it's actually kind of interesting. You know, you go through the whole process of, you know, trying to understand, you know, what's what's going on in - well as a biologist, an ecologist - you're trying to understand what's, what's happening in an, in an ecosystem. And, you know, you carry out a study and you find something out. And very occasionally, if you're lucky, you find out something new that, that’s maybe not generally recognized. And if you're aware of the the field, you'll realize that, “hey, this is something actually different and new”, and that doesn't happen very often. I mean, that might happen once or twice in a career. So if you're lucky enough for that to happen at all, I think you're you're in really good, good shape. And I guess in in my case, through some analysis, sort of understood how diffuse light, so light that's been kind of gone through clouds or a canopy can be more effective at you know, plant growth than, than direct sunlight. So it's it was kind of an understanding that the quality of light in terms of where it comes from is, is important. And, you know, that's not of perhaps general interest, but within the field, it has consequences for modeling. It has consequences for how you might sort of, you know, manage things like that. So that was, that was an interesting sort of, you know, time to sort of say, “oh, this is, this this actually makes a difference”. And that wasn't generally realized I think at at the time. But now, of course, it's you know, many people have gone on and, you know, gone in many different directions in with that same sort of, done much more research in that area. It's still neat to sort of, you know, have that that opportunity within science to sort of, you know, see something, you know, what appears to be new. I mean, it's been there all along, but you've brought it at least to, to the realization, you know, of the the scientific community.

Part 2: How to Convene (and Conclude) a Successful Climate Hub

Recorded on December 8, 2022

It wasn't really clear what a hub was going to be at that point. It was there were a lot of a lot of ideas floating around. Some of them had to do with a lot more research because the kind of undersecretaries had gotten together of USDA to try to formulate what what the hubs would do. And they were they were always supposed to be climate outreach, but there was a very high research, sort of cutting edge research component in the beginning. But it's very difficult to do both of those things, especially, you know, given the limitations that were available and in people and resources. But I think there was already a lot of research going on, you know, related to climate change within Northern Research Station and the other Forest Service and, you know, ARS Labs. So but this outreach, you know, really was was something was something special. And I remember the Northern Research Station director at the time asking me and and another scientist at the time, you know, is this something that we should be involved in? And so we spent spent a whole summer really putting all the pieces together. Had we had to write a proposal to sort of lead a climate hub, you know, lots of meetings, you know, found colleagues in the Agricultural Research Service and then NRCS that were also interested in participating. So we put it in, we weren't sure what was going to happen, but eventually they that was one of the ones that was that was successful. So. The Climate Hub was a really interesting challenge because, you know, by and large, you were working with a group of talented people, but you had no, if you will, supervisory role. So, you know, the you didn't have leverage, you know, you know, the if you will, of course, kind of leverage where you were all, you know, working in the same unit towards the same goal. You had people that were in in different parts of the agency, different parts of their career. They had different main goals. You know, their research goals that were part of their agency and part of their working groups. And it was then to as as a group, kind of come up with sort of goals, outreach goals and sort of and synthesis goals. Because I think the climate hubs, you know, when they were first put together, they were outreach and research, as I as I mentioned. But I think a really important aspect of the climate hubs has been that sort of synthesize. So basically go through research, both climate research and and, you know, other information about adaptation and whatnot and take the various pieces together, understand them fully yourself so that you can explain them and, you know, to to others. You know, the great thing is and these are talented people. So it's it's really just trusting people to understand the issues or maybe working to help them so that you're all on board with with what the issues are and then just letting them go with it. And and when you so it's I guess a kind of a participatory sort of leadership in that it wasn't myself making all of the decisions which, which is is really important because first of all, I don't know all the answers. I have a certain background, but there were other people in the hub which had very different backgrounds and special understanding in soils or agriculture, agronomics, economics, all of these things. And so you really trust those people to to use their experience and insight to help, you know, make these overall decisions. And so when you when you do that, you really do then have to sort of say, you know, that's the way we're going to go. And that includes making decisions about where the money goes. Because that’s, you know, if you're not really listening to other people and letting them make those decisions, you're not empowering them to sort of take things on. And if if people realize that that they're sort of in the driver's seat or at least sharing the driver's seat, they're much more interested and they can sort of, you know, drive the bus to that particular area where they think it should go as well. So it's worked out, you know, very well, at least from from my standpoint. It's also it's also probably easier, you know, if people if you have other people that are very knowledgeable and have good ideas about where to go, then you just, you know, stand back, get out of the way and try to find the resources to let them get there. And that can actually make your job a lot easier. You're not trying to be some sort of expert in everything. It it was also we were able to sort of, I guess, align the interests of the hub with the the co-directors. And I think that was really important for, you know, the participants to feel that they, you know, co-lead the hub. So the, you know, the the title is not it's not meaningless. I mean, if you're a co-director, then you are you are directing, you are you're part of the team in doing that. And, you know, we had ended up with a lot of co-directors, but then we ended up with a lot of people, you know, helping, helping lead the way. So. I know one of the other questions was where did I want to see the climate hubs and in five years or something? What I would really love to see is the maybe five years, five years for sure will be too soon. But but ultimately, I would love to see the climate hubs gone, because that would mean that we don't need them anymore. And that would mean that everybody is on board with adapting to climate change or mitigating it. It’s a combination, really. And the trouble, of course, is adapting to climate change works for a lot of people because it's in your own interests. You're you're changing your management. You're changing some aspect about your system that allows you to continue to do what you're doing and to sort of thrive economically. Mitigation, you know, storing carbon isn't necessarily, you know, in your financial interests or it may actually cost money to do that. And so, you know, you have to I think we have to remember that people they have to make a living first and foremost. And and if and sort of empowering or incentivizing them to do that in terms of mitigation is is a challenge. And that's a place for you know, the government hasn't quite decided how it's going to do that or if it's going to do that. You know, I suspect it will. We’ll, we'll have to see. But yeah, ideally it would be great if we don't need the climate hubs anymore because people have all that information and they're already motivated and they're they're doing all that stuff. So that's that's my my long term vision for the climate hubs is, is, you know, gone. That's that's how I know will be a success.

Part 3: Better be a Climate Optimist

Recorded on December 8, 2022

I think it would be difficult actually to work too much with climate change if we weren't optimistic. But I see a tremendous amount of change actually happening. So, yes, the CO2 is still going up each year and yes, the temperatures are rising and all of these other changes are well underway. There's no doubt about that. But I also see really big changes happening in the sort of underlying infrastructure around the world. One of the things that used to give me and still does gives me a tremendous shot of optimism is the Energy Information Agency. It's a... and there's also an international energy agency. But these monitor fossil fuel use, energy use and the source of energy. They also, you know, have their own projections about the future. And for years now, you know, wind and solar energy have been sort of increasing and increasing. And for a for a number of years now, the greatest capacity additions to the US electrical generating infrastructure have been wind and solar and and they haven't built new coal plants in probably more than a decade now. And the coal use is just just dropping away. And, you know, the renewables, solar and wind are set to set to pass even natural gas generation, you know, in a few more years as the largest source of energy. So there are a lot of these trends that have been underway for a long time. But they they've taken a number of years to really get to the point where they're impacting the overall, you know, energy mix and therefore CO2 production. At the same time, I actually think that this year, probably last year, really, society has hit a tipping point in terms of dealing with climate change. I mean, Europe and China have been ahead of us, but there is no automobile company or that is not putting all of their chips into the electrification, you know, game now. In Europe, you won't be able to sell a car or a new car with an internal combustion engine in less than a decade... so, or maybe it's just over a decade, but these these are investments that, you know, in battery factories and everything else that they're not going to pull back. So we are we are firmly sort of over the top in terms of sort of electrifying our, the transportation sector, which is the largest sector. You know, the government in in this country and pretty much most of the rest of the world are looking at climate change and addressing climate change as you know, one of the very most important tasks and they are actually doing it, you know, in Europe, they there are laws in a number of countries about being net zero by some sort of timeframe and typically before 2050. And that's that is tremendously hopeful to me. I mean, within, you know, the climate hub in the whole climate world, we we've talked about these scenarios of of greenhouse gases. And, you know, basically that the various climate models use these potential trajectories of greenhouse gases to estimate or calculate some sort of change in the future climate, how much warming is going to happen, and how precipitation is going to be shifted around in the globe. But the very worst models are really, really based on a huge increase in greenhouse gases. So we've had a big increase so far, but we have not had a huge increase. We've not had and honestly, I mentioned we're over 400 parts per million now, but the in the RCP 8.5 scenario, which was the sort of what they used to call the business as usual scenario, we would be near 1000 parts per million by 2100. So in 70 years. So we would go, you know, we would, we would be two and a half fold almost, you know, beyond what we are now. And that's not going to happen. You know, I expect the global CO2 emissions to sort of peak in the next couple of years, which is which is phenomenal because, you know, some of those higher scenarios, they were continuing to increase right through 2100. And that's I think that's very unlikely. The assumptions that went into these very high scenarios are just not being met. The energy mix is becoming much less carbon intensive and at the same time, energy use is becoming much more efficient. So the amount of energy used for per dollar of GDP or something like that is declining. So all of these factors are in some sense happening far quicker, I think, than a lot of folks within the climate change world are even aware yet. So the trends are powerful. And I'm also optimistic because there have been a number of other environmental problems too, that within my career I've experienced. I remember when lead in gasoline was a really big issue and it was a difficult one. And, you know, we heard from many people that they couldn't remove the lead from gasoline because it was just too too difficult or too expensive. And, you know, other people, you know, where the lead levels were, you know, leading to, you know, just all sorts of issues and, you know, mental issues in people and children in particular, because it's, you know, a neurotoxin. But, you know, laws were passed and lead was removed from gasoline and it didn't destroy the automobile industry. And we're better off. And the same thing happened with acid rain and the same thing has happened with the ozone depleting substances. And you can go back further and look at DDT. You can look at, you know, surface ozone. I remember reading a paper, I don't know, a few years ago that was predicting that that surface ozone levels were going to be so high that, you know, we were all going to be I don’t know... Oh, they they basically extrapolated that change. But in each of these cases within the U.S., you know, Congress passed a law or allowed the EPA in the case of ozone, to reduce the maximum levels that were there. And the EPA has done that a number of times. And the air is measurably cleaner. Rivers are measurably cleaner than than they were in the past. So just seeing what can be done, you know, that that we can do that without it destroying our economies is very kind of affirming and does lead me to be optimistic about dealing with with CO2 as well. So it's the history and it's the reality of things that are already now in motion. So I'm even optimistic that we can, you know, rewind some of the levels of CO2 in the atmosphere. Another greenhouse gas that can be a problem is that is a problem is methane. And that's been going up rapidly as well. But methane is really exciting because it is naturally destroyed in the atmosphere. And if the sort of emissions drop below the sort of, you know, present rate of destruction, the amount of methane in the atmosphere will drop very quickly. And I know the administration and the world is actually focusing, you know, efforts on methane just because if you get a grip on it, you can, you know, wind that wind the warming associated with methane backwards very quickly, you know, basically, we're going to have to reduce the fossil fuel, continue to reduce fossil fuel use. And we actually in the US by you know moving away from coal and going towards renewables, we actually have cut the the CO2 emissions as a whole. But there may be a certain number, a certain amount of emissions that are very difficult to get rid of. Some people talk about aircraft, for example, because, you know, fossil fuels are very energy dense and there's more energy per kilogram, if you will, of you know, kerosene for a for a jet plane than there is in, you know, typically batteries and whatnot. So it's hard to figure out how you may be able to get rid of that, although, you know, there are ideas with with hydrogen and with biofuels, things like that, that's, you know, we'll have to wait and see how that works out. But that may be slower. So it may be difficult to get to net zero. And that that may be where using some of the natural capacity of the biosphere to take up carbon will be, you know, useful to us all. One important realization or point for all of us is that the better we are at reducing fossil fuel emissions, the better we are at mitigating these sources, the less we're going to have to adapt. Okay. So if we were, you know, if we were perfect, if we, you know, and suddenly shut things off tomorrow, then, you know, adaptation is going to be pretty minimal. So I really hope that people, you know, focus on mitigation so that the conditions that we have to adapt to the changes in temperature and rainfall are not so large that we can't adapt to them because we're going to have to keep adapting if we don't mitigate. If we don't if we don't reduce, you know, fossil fuel emissions, you know, we're we're adapting for conditions in ten years, but ten years from now we’ll be adapting for conditions that will be that much warmer. And that that won't ever end if we don't do something and then we will hit some sort of tipping point. So embracing these these opportunities to, you know, convert, you know, the agriculture and forestry to lower carbon operations, you know, I think the hubs should maybe be sort of talking more about electric tractors or something like that or or other ways of drying grain that don't require, you know, such high fossil fuel usage. You know, fertilizer is, uses a tremendous amount of fossil fuels. And, you know, I think a focus on fertilizer efficiency and, you know, reduced nitrogen use is probably another place the government is going to go because you save the emissions of the fossil fuels, you also reduce the nitrous oxide emissions and that’s... N2O is one of the harder greenhouse gases to deal with once it's emitted because it sticks around in the atmosphere for a really long time. And unlike methane, which is, just goes right away. So long term N2O we really going to have to come to grips with that. So so yeah, the more we mitigate, the less we're going to have to adapt. And so I guess that would be my first concern. And the rest is, is yeah, just have to, you know, work with people, use their knowledge and experience that they have, especially, you know, the producers and forest landowners out there that have seen, you know, how their land responds. And, you know, just try to find neat, you know, cost effective, scalable solutions so that can turn things around.


Durham, NH

Project Status

Dec 8 2022

Project Lead