The Breath of Lake Superior: Lakes in a World of Rising Carbon Dioxide

December 2023 Twin Ports Freshwater Folk


Daniel Sandborn, doctoral candidate, Water Resources Science, Large Lakes Observatory, University of Minnesota Duluth.


Wednesday, December 6, 2023


11:30 a.m.-1:00 p.m. CT


Virtual registration

Event schedule:

  • 11:30 a.m. Meet-and-greet breakout sessions
  • 12:00 p.m. Announcements by attendees
  • 12:05 p.m. Seminar(s)
  • 12:45 p.m. Moderated question and answer
  • 1:00 p.m. Adjourn

About TPFF:

Twin Ports Freshwater Folk (TPFF) is an informal gathering of people from the Twin Ports of Duluth, Minnesota and Superior, Wisconsin, who are engaged in freshwater research, policy, or regulation issues, for networking and informal discussion. Meetings take place the first Wednesday of every month.


Water Resources Science Doctoral Candidate Daniel Sandborn from the University of Minnesota Duluth Large Lakes Observatory will provide an overview of the work detailed in the published preprint: Underway pCO2 surveys unravel CO2 invasion of Lake Superior from seasonal variability.


Carbon dioxide gas concentrations were measured in surface waters of Lake Superior for four years, forming the first multi-year dataset of direct observations of carbon dioxide gas concentration in the Laurentian Great Lakes. Lake Superior’s surface carbon dioxide concentration was closely tied to that of the atmosphere on time scales longer than one year. Seasonal variations in carbon dioxide concentration were driven by water temperature, biological activity, river influence, and gas exchange with the atmosphere. Lake Superior released and absorbed carbon dioxide cyclically at different times of the year, absorbing more than it released from April to November. Mixing surface waters maintain the same carbon dioxide concentration as the atmosphere (which is increasing due to anthropogenic emissions), so the partial pressure of carbon dioxide gas in Lake Superior surface waters increased over the past two decades. This work improves the scientific understanding of carbon cycling in Lake Superior and advances techniques for carbon cycle observation and modeling of other lakes.

Event sponsors:


Sign up to receive notifications about upcoming TPFF events.


Alex Frie, research and fellowship coordinator, Minnesota Sea Grant, University of Minnesota and University of Minnesota Duluth.

Image credit: Daniel Sandborn