"CO2 levels have bounced around between 180 parts per million and 280 parts per million from one glacial cycle to another," Horn said. "Now we're at 390. I was looking to learn how nutrient utilization changed in the Southern Ocean and what kind of variability that has on CO2 levels over Earth's history and see what it means for today."
While this latter project did not involve travel to the Southern Ocean, he still looks back nostalgically on his time spent at sea.
"Life is simple at sea," he said. "It's just you and your work. You get to know the people you work with well, you see so many new places, and you see a lot of water. There was great excitement in the unknown. But I also enjoyed seeing a different side of oceanography with all of my lab work, too."
After graduation, Horn will begin work as a chemical oceanographer at Applied Science Associates, just a few miles down the road from the URI Graduate School of Oceanography. He looks forward to applying his diverse background and experience to the company's projects tracking oil and chemicals in the ocean and addressing other coastal and environmental hazards.
"I'm looking forward to getting out of academia and working in the private sector," Horn said. "Some day I may see myself starting my own company or maybe try teaching. But I've been in school for 25 years now; it's time to spread my wings a little bit and make a difference."