Who I am and what I Do
In my work, I study the ways that living things (the biosphere) and the atmosphere interact with each other, focusing on life on land.  Through photosynthesis and the evaporation of water from plant leaves, seasonal cycles of growth and decay, and occasional big events like fires, the biosphere on Earth exchanges heat, water vapor, carbon dioxide, methane, nitrogen in different forms, and many other compounds with the atmosphere.  These exchanges result in the biosphere actively controlling the climate of the Earth.  If we understand this better, we can predict weather better, and we can also try to figure out how these exchanges could be different for life on another planet. A lot of my work involves computer modeling— using weather variables like light, temperature, and rain.  Using those, we hope to predict how much carbon dioxide an ecosystem will take in from the atmosphere and how much water will be released from the soil back to the atmosphere. I also sometimes do fieldwork, like setting up scientific instruments in a forest to measure the changes of carbon dioxide and water vapor, or to measure the reflectance spectrum of the leaves. The way leaves reflect at different wavelengths of light can distinguish different kind of plants and tell something about the plant's health status and other properties.

Areas of expertise
It's always good to have good math and statistics skills—in any science. This helps you to interpret data, especially when there can be complex relationships. And it enables you to theorize about new possible relationships that no one might have thought of before. Also, basic physics and chemistry are important. My field requires knowledge from a lot of different fields—meteorology, atmospheric chemistry, ecology, soil development, and plant physiology. All these things are related in Earth System Science, in which we try to understand how elements cycle through the atmosphere, the hydrosphere, the exosphere, and the biosphere. Environmental engineers will also share a lot of the same technical expertise, but they may apply it more to fixing up a messed-up ecosystem than toward trying to understand what the Earth was like in the past, might be like in the future, or how life might happen on another planet.

How I first became interested in this profession
When I first started graduate school at Berkeley, I was interested in solving environmental problems. While taking courses and learning more about the science, I got interested in Earth System Science. I was particularly intrigued by courses that provided a global understanding and touched upon the Earth's history. I have always had a love of astronomy as a kid, so when I graduated, I was very happy to be able to put together Earth Science with searching for life on other planets.

What helped me prepare for this job
My schooling, of course, trained me for a lot of what I do.  What was most important to learn was not just the technical skills, but also the ability to be an independent researcher, pursuing the unknown out of your own curiosity, and realizing that no one else can give you the answer. However, you can and must talk to many people and play your ideas off of them, as well as gain knowledge from their special expertise that you might have trouble figuring out on your own. If you would like to pursue research in science, it is important that you not be afraid to ask questions and to find a good mentor or two who can help you figure out the foundations you need to pursue your interests.

That was good practice for being a scientist.

My role models or inspirations
The best role models for me were not only intellectually excellent but also personally wonderful people who could balance their family with a very busy job and manage their laboratories well, respecting everyone as individuals. These included not only professors but also co-workers at previous jobs before I went to graduate school.

My career path
Since neither Earth System Science nor Astrobiology are traditional fields, most people arrive at them in indirect ways (now there are graduate programs in these fields). I graduated from Stanford with a degree in computer science. I was interested in solving environmental problems and pursued a master's degree in Energy & Resources. In learning about human impacts on the environment, I learned more about ecology and the cycling of elements through the Earth as a system. So, I went fully into natural science for the Ph.D., because I liked the mix of mathematical modeling and physics with biogeochemistry in biometeorology, I focused on that for my thesis. My thesis looked specifically at a single ecosystem, so for my next job, I wanted to get a bigger picture.  I found an opportunity to do global scale modeling at the Goddard Institute for Space Studies. I was also highly inspired by the Virtual Planetary Laboratory, so I have been introducing a biosphere to their extrasolar planetary model."

What I like best about my job
Anything I like to read, from Einstein to Asimov, is fair game for an idea. I never feel narrowly focused, but I get to work with astronomers, biologists, climate scientists.  I can work at home or in a nice café. They give away fun toys at AbSciCon, an astrobiology conference.

What I like least about my job
I always feel as though I don't know enough.

My advice to anyone interested in this occupation
Learn the fundamental sciences well (math, physics, chemistry, biology) and find a summer course or job at beautiful place like Woods Hole Marine Biological Laboratory or a NASA summer camp where you can have a hands-on project to work on with fun people. When you go to graduate school, find an advisor who has a happy group of people who like to interact a lot with each other.

Personal information
Hobbies: photography, violin, painting, writing, SCUBA diving.

Last Updated: February 15, 2005