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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

Release Date: February 2023

Part 3: Better be a Climate Optimist

Release Date: March 2023

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Durham, NH

Project Status

Dec 8 2022

Project Lead