St. Olaf Magazine | Fall 2021

The Tree Counter

Ann Raiho ’11, the second member of the Hudson Bay canoe team, has been as busy as her boatmate, Natalie Warren ’11, since their epic voyage. After graduating from St. Olaf with a mathematics major and an environmental science concentration, she completed a master’s in ecology from Colorado State University, a Ph.D. in ecology from Notre Dame, and postdoctoral research back at Colorado State.

Where are you working now?

I am employed by NASA as a contractor through the University of Maryland, working remotely from Colorado. I am part of team on a satellite called Surface Biology and Geology, which is still in the planning phase. The Earth Observatory Group is our informal name.

How would you describe your doctoral work in a nutshell?

My research focused on fusing complex ecosystem models with paleo-ecological data to inform unobservable long-term — decades to millennia — processes in forests. I worked with paleo-ecological data, which is fossil pollen taken from the bottom of lakes, and tree-ring records. I used those data along with mathematical models to better understand how forests change over long periods.

Could you give a specific example?

We used fossil pollen collected from over 200 lakes in Minnesota, Wisconsin, and Michigan to re-create forest characteristics like biomass from the past 10,000 years. During this time, many species shifted their geographic distributions. Understanding the exact timing and magnitude of these shifts gives us a better idea of how trees may respond to climate change in the future.

What is your satellite project designed to accomplish?

The satellite gives us so much more information: it takes a picture of every place on earth every 16 days, thus giving us a lot of repeat information. There could be many more big trees out there that we don’t know about, taking up a lot of carbon. None of the current models agree on how much carbon is being taken up by trees; this satellite data should help us better understand that.

How is your work related to climate change?

Trees live a long time. Over thousands of years, different species will migrate when climates change. With Earth’s climate changing rapidly now, we’re trying to plan for the future and determine where plants will thrive — and not thrive. Long-term data showing how plants have moved in the past will help us figure this out for the future. The satellite’s spectrometer takes pictures of things we can’t see, such as nitrogen content, cellulose, etc. We’re hoping to map plant characteristics from space and see how they change over time.

Did your time in the Boundary Waters affect your interest in ecology?

Absolutely. When I was younger, I read a lot of research about the Boundary Waters turning from a boreal forest into an open savanna because of climate change, so I have long been worried about global warming transforming the wild places that mean so much to me. And, of course, this is happening at a global scale as well as at a local one.

Did any particular part of your St. Olaf studies influence your later career?

The Biology in India study abroad program set me up well for a lifetime of independent research. I often think back to that program as a true turning point. Eight of us were sent out in pairs to two different field stations in the Tamil Nadu area of southern India. We spent four to six weeks doing an independent study project at each site. I looked at women’s nutrition and food insecurity in one study and where different butterflies lived in my second study. I was just 19, and it was mostly just me trying to figure it out on my own. Those independent research skills that I’ve used so much really started developing then.

What advice can you give to young Oles who share your passion for the environment and concerns about climate change?

Climate change is a global and complex problem, and a solution will require many types of people with a great variety of interests and skills. For me, my strengths and interests have always been in math and wilderness environments. Focusing on these interests led me to a career in global change ecology. In college, having a wide variety of experiences but also sticking with something (math) that I felt was important and unique helped me realize this path. At the time, I didn’t see the connection between my interests, but I instead felt that I could be flexible with my path. I always took opportunities that arose that fit with my background in math and ecology while also adding something I didn’t know much about but was interested in.

In the short term, I recommend to students not to say no to an opportunity that sounds interesting to them, to search actively for more opportunities, and to step back often to see the bigger picture of how what they’re doing or the path they plan to pursue contributes to the global effort to solve the climate crisis.