Margaret Conley ’18 Continues Harvard Forest Study to Better Understand the Carbon Sink in the Terrestrial Biosphere

In 2006, Battle and his colleagues built a proprietary data collection system for placement in the Harvard Forest. The Harvard Forest, in central Massachusetts, is a private facility endowed by Harvard University for use by scientists interested in a range of fields, from atmospheric chemistry to entomology.

Battle's study uses air samples to measure carbon dioxide and oxygen levels in the forest's atmosphere over time. The ratio of carbon dioxide to oxygen varies with the forest ecosystem's natural processes, like photosynthesis. As such, the atmospheric ratios differ depending on the processes in the plants at any given location. Thus, the data Battle and his students collect can help determine how much carbon dioxide is being consumed by the forests, i.e., sinking into the terrestrial biosphere, as opposed to sinking into the ocean.

As the study has progressed, Battle has hired a number of students to assist him with data collection and processing. Conley made this work the focus of her honors project, which culminated in the production of a research paper and presentation.

In order to more accurately interpret the mass of data collected over twelve years, Conley made use of an application produced by the National Oceanic and Atmospheric Administration (NOAA) called highsplit:

"The highsplit allows us to trace where the air came from: we can track the path of a parcel of air backward through time," she said.

By tracing the path of air entering the forest, Conley compared and contrasted the impacts of local and long-distance air exchanges. Conley said her typical day working on the project includes "graphing, using Matlab, splitting up the data into manageable chunks, and designing simple models to determine the relative importance of air source and local exchange."