By JD Capuano
Cook’s recent work focuses on the linkages between land degradation, drought, and climate change. What makes him a rarity among climate modelers is how often he has gone on field excursions with research scientists. He travels to remote locales with research teams to help gather the raw materials he eventually uses in his models.
We recently spoke in a conference room of a building tucked away just south of Columbia University’s main campus in Northern Manhattan.
Your colleague, Kevin Anchucaitis, said you go into the field with the research scientists. He said this is a rare thing for climate modelers. Why do you do it?
It’s fun. There’s a tendency for a lot of us who are on the computational end of things to get a little far removed from where this data actually comes from. And so most of the field trips I’ve been on have been expeditions to find old trees. Through dendrochronology [the formal term for tree-ring dating], you can do tree ring reconstruction to get a time series of climate. I can get all the data online if I want to, but going out into the field gives you a little more of an appreciation of the work it takes to get these time series, and that they don’t simply appear like magic on the NOAA archive.
How long have you been taking core samples from trees?
Oh, off and on for 10 years. My father was a dendrochronologist and so I sort of caught the bug from him and … well that’s not really what I do, but I certainly know enough to help people with that sort of stuff.
I noticed in your bio that despite your best efforts, you’re also a part-time dendrochronologist. Why despite your best efforts?
Yeah. It’s sort of a joke. He [Cook’s father] is part of the reason I got really interested in environmental science. I like dendrochronology, but it’s not something I get very passionate about.
What do you get passionate about?
Drought, which I guess may be a weird thing to say. But as far as climate events that have a really big impact on people and ecosystems and societies, droughts really rank up there. In a lot of cases, people and ecosystems and species can sort of adapt to slowly increasing temperatures, but if you run out of water, you’re at the edge of a cliff. And so I got very interested in that my last year of graduate school. Then I did a postdoc here at Lamont with Richard Seager where we looked at the Dust Bowl—this major societal event that happened in the 1930’s.
Where else do you study droughts?
Mostly Southeast Asia. I’m involved in one project looking at variability in the monsoon over Southeast Asia. [We’re] trying to see what drives drought variability in that region. That’s another area where if the monsoon rains are late or weak, then it makes a really big difference to a lot of people.
You spearheaded the analysis of 114 years of uninterrupted weather data from Mohonk Preserve in Upstate New York. Your father was involved. This project seems like a convergence of the personal with the professional. What got this ball rolling?
It was my father working there in the late ‘70s. And then when I was in grad school, we were talking and he mentioned these long records of plant phenology, you know, first flowering dates. Spring events tend to be very sensitive to climate. If it’s warm, you get an early spring with early flowering. If it’s cold, you get a late flowering.
These sorts of long time series datasets are rare, especially in the U.S., so he suggested we do some sort of project together with this data. That’s how I started to get into the Mohonk scene. And that’s the first paper we did together looking at these plants and how they’re changing over time and what their sensitivity to temperature actually is.
It was kind of a fun way to do something with my father. So you’re right, it was this interesting sort of personal thing, a piece of research that we were both really interested in and excited about that we could work on together. That was pretty neat.
It’s unique having that continuous record there. What does that mean for climate science in understanding what’s been happening in the last 100 years?
You know, it’s one piece of the bigger picture, but it’s always fun to find a piece like Mohonk. [It] not only has really long levels of climate and ecology, but the way it was all set up by the Smiley family was with a very scientific mindset. To have this data under strict protocols by people who really cared about the science aspect of it is rare. So it’s fun to revisit those specific sorts of cases where we have data we know is high quality and asking, “Okay. Does this support the bigger picture that other people are putting together at the global and regional level?”
Do you find other scientists going to the Mohonk data to help them figure this out?
I think people have been excited about using the Mohonk data in a larger framework. One of the exciting things we found was looking at the temperature record. It looks exactly like the global hemisphere temperature. The trends and the variability are spot-on with the global record. [It shows] warming up the ‘50s, slight cooling, then warming since the ‘70s. This is just one random spot in New York. And this gives us confidence. Here’s this high-quality record that reflects what’s happening to the globe, which gives us a little more confidence in global and local interpretations.
What originally got you into science and climate science?
It was a few things. When I was in middle school and high school, my father used to take us on a road trip out west every summer, usually for about two or three weeks. And part of it was that he would go visit buddies at other universities and we’d go into the field and core trees and that sort of stuff. So that was part of it.
I had always been interested in science and went to school for environmental science. It was my senior year when I really started to think, “do I want to go to grad school and what am I really interested in?” That’s when I started learning a little more about climate and global-scale problems. And that’s when I got really excited about that because it seemed something very globally relevant.
I asked you earlier about going out into the field. Why is it rare for climate modelers?
Well, it’s not rare in a bad sense. Mostly it’s because we’re funded to do certain types of work. So my primary funding is to work on a model, right? If I’m getting paid off a grant or some project to work on the model, then there’s usually not money in there for me to go into the field. Part of it too is that I’m lucky enough through Kevin and my father to be hooked into a lot of people doing really interesting paleo research in the field [paleo refers to paleoclimatology, the study of climate prior to human measurement using tree rings, corals, sediments and glaciers]. So I think a lot of it is people doing their own thing and they just oftentimes don’t have the opportunity. Whereas I think a lot of them actually would love to go out into the field and see how this is done.
What do you like most about being in the field?
It’s a little Indiana Jones, you know? You’re hiking through these really old forests and whenever you find something really cool or intellectually exciting, it’s always a kind of rush, you know?
On one of the most recent trips I went on with Kevin we found—we didn’t even know it at the time—but it turned out to be some of the oldest trees in Southeast Asia. We found them on this ridgeline and we weren’t even there for those trees. We cored them, brought the cores back, and had them worked up. They turned out to be the basis for this 700-year long reconstruction of drought in Southeast Asia. It’s always kind of exciting when things work out.
