LYNDONVILLE — What happens when climate model projections for the Northeastern United States are based on outdated or inaccurate temperature estimates of large bodies of water such as the Great Lakes? That’s what Northern Vermont University Associate Professor of Atmospheric Sciences Janel Hanrahan and two NVU student interns set out to study in summer 2018. The results of their research were recently published in the Journal of Applied Meteorology and Climatology in the paper titled, “Examining the Impacts of Great Lakes Temperature Perturbations on Simulated Precipitation in the Northeastern United States.”
“This internship provided undergraduate atmospheric sciences students with first-hand experience working with climate model data and publishing in a peer-reviewed journal, something that many students don’t do until graduate school,” Hanrahan said.
As climate scientists work on projections for future precipitation in the region, they questioned the impact that warming water temperatures of large lakes may have on those projections. Hanrahan said modeling software typically assigns estimates to lake temperatures. But given the wide variability in the surface water temperatures of the Great Lakes and the warming that’s been occurring over the past few decades, Hanrahan and her student team — recent NVU alums Jessica Langlois, Class of 2019, and Lauren Cornell, Class of 2020 — set out to see if altering the surface temperatures in the model would impact the precipitation projected in the Northeast.
They found it would. “By using varying temperature values of 10C below and above the baseline temperatures, we could see the impact of those temperature changes on precipitation projection,” Hanrahan said. “If we’re trying to project future rainfall in 2050, but don’t have accurate Great Lakes data, we won’t get an accurate projection.”
“This project, which will inform regional climate modeling moving forward, allowed the students to collaborate with scientists from Dartmouth College, the University of Vermont, and the National Center for Atmospheric Research,” Hanrahan said.
The research was funded in part by the Vermont EPSCoR Basin Resilience to Extreme Events (BREE) project.