Ralph Keeling knows as well as anyone what it’s like to have big shoes to fill. His father, Charles Keeling, began tracking the concentration of CO2 in our atmosphere at regular intervals in the 1950’s, showing an obvious and steady increase over time. These results, graphically accessible as the now well-known ”Keeling Curve,” sparked scientific interest in the effects of CO2 on our climate in the 1970s, and continue to serve as an invaluable resource for scientists today.
A prominent climate scientist in his own right, Ralph Keeling serves as director of the Scripps CO2 Program, where his father’s historic work started. His research tracks oxygen levels in our atmosphere, adding valuable new information to the complex picture of how our environment handles increasing amounts of CO2.
We talked to Ralph Keeling to find out what it’s like to follow in a famous scientist’s footsteps, and the windy route that led to his own established career.
Did you always know that you would become a scientist like your father?
By the time I was a teenager, I was interested in science, but didn’t know if I’d be any good at it. You don’t really know at that age where your talent lies. I was inspired by my father’s work, but I hadn’t fully digested it, so I went off to college exploring different areas of science.
I was a chemistry major for a while, and I decided to not major in chemistry because I got tired of doing chemistry labs. I didn’t think they were a good use of my time, and I would defend that, even today. The intellectual benefit for the hours put in was not a balance, I thought. I love gadgets – if we were playing around with gadgets and learning how to use gadgets, that would have been fine. But this business of writing down the procedure, method, hypothesis and the conclusion, looking up everything in the journals for something that is basically a fake experiment anyway, because someone’s already done it – there was no exploration. You’re trying to bake a cake and make it turn out and then describe it as science, and I didn’t find that very illuminating at all. I would have loved a course where you just repair equipment – that would have been fantastic.
What did you decide on?
I majored in physics and dabbled a little bit in earth sciences, so in that sense I was a bit like my father. I hadn’t been too guided by him, up until that point. [Then] I went to graduate school, [still] not sure I wanted to do earth sciences. I was interested in areas of fundamental physics, so I went to Harvard in applied physics, in part because it gave me freedom to still decide what I really wanted to do.
I had kind of theoretical interests, but I went through a bit of an epiphany my first or second year of graduate school. I felt like putting my life into areas of fundamental science was less in tune with the times than putting my career into some aspect related to the changing planet. The planet was changing under our feet, and it was important to get going and look at it. I felt like there weren’t enough people actually studying what was happening to the environment at a time when it was undergoing massive change. Fifty years earlier, maybe fundamental physics would have been more transformative. But I felt like this was socially more relevant, and in some ways, maybe for that reason, more interesting.
I also made the switch from thinking I wanted to do theoretical science to doing experimental science. It was a very separate thought process. I felt like doing experiments was going to lead to a richer life, in that I’d be interacting with more ordinary people, not just sitting behind a desk.
How did your graduate work evolve to match your interests?
The best opportunity at Harvard, I felt, was to work for a professor who was doing stratospheric photochemistry, a guy named Jim Anderson. He was the first person to demonstrate that there were chlorine radicals in the stratosphere. But I actually wasn’t that interested in photochemistry.
It was around that time or a little before that I first really appreciated my father’s data. I knew my father worked on carbon, but I hadn’t really seen his data, and it was at that point that my father really started explaining his work to me. And I [had] carried away from a conversation with him, several years before I went to graduate school, that maybe you might want to measure oxygen in the air. I was kind of adrift in graduate school, not being sure I wanted to do photochemistry, so I was investing time in figuring out how to do oxygen, because I had the freedom to drift around.
You might think that Jim Anderson would have been disappointed that I wasn’t doing something closer to his interests, but he was all for it. He said, “We gotta do this! That’s big, measuring oxygen – I bet you can do it, Ralph! And the only question is whether you’ve got enough patience, but we can pull this off if you have enough patience.” It was fantastic advising; I took a lot away from his spirit of “can do.” I really benefitted from the wonderful group he had, people with diverse talents, which I needed as I worked on this project. He basically gave me the freedom to be an independent scientist at a very early point, pursuing research that I conceived of by myself, but with backing from a really strong group and really strong mentor.
Special thanks to the Department of Earth & Planetary Sciences; the Initiative for Sustainability and Energy at Northwestern (ISEN); the Program in Environmental Policy and Culture; and the Environmental Science, Engineering and Policy Program who hosted Ralph Keeling at Northwestern’s annual Climate Change Symposium this fall.