High frequency observations of under-ice convection

Abstract eng:
High-frequency observations of thermal structure under the ice of a large lake reveal the presence of large (10-20 m) overturning convection cells, driven by solar heating. Two winters observations are used to quantify the under-ice mixing and dissolved oxygen dynamics. The most vigorous convection occurred near the end of winter, as the water surface layer started warming, with a gradually deepening of the mixed layer over time. This coincided with the prediction by the Canadian Lake Ice Model of when the ice cover began to melt and decrease in thickness. During the same period the dissolved oxygen had become super-saturated from the surface to 23 m below the surface, suggesting abundant algal growth. Thorpe scale analysis revealed that very large scale mixing occurred beneath the ice; the mixed layer depth increased during the melting period, and mixing was most active during the day.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket