Lake Superior Ventilation and Dissolved Oxygen Cycle

Lake Superior is one of the largest lakes in world yet its circulation, especially in the interior, is not well understood. Ventilation rate of the lake interior is key to determining the vertical distribution and fate of natural and anthropogenic tracers. In this study, we utilize “age” and “dye” tracers in a realistically configured numerical model of Lake Superior to characterize its ventilation. We find that Lake Superior is preferentially ventilated over rough bathymetry and that spring overturn following a very cold winter does not completely ventilate the interior. Also, dissolved oxygen in Lake Superior is not a good proxy of ventilation age, as expected from oceanography, because the lake is so strongly physically dominated.