Water Circulation in Small Arctic Lakes in Winter

Dye experiments and detailed measurements of conductance and temperature in small lakes at Saqvaqjuac (63°39′N, 90°39′W), showed how water circulated in midwinter. Stored heat returning from the sediments warms adjacent water, which then sinks downslope. Water immediately beneath the ice moves laterally shoreward, picking up cryoconcentrated salts and sinking downslope. Displacement of deep waters upward at the lake center is postulated as completing the circulation. Rates of water movement are on the order of 10 m∙d −1 in 2- to 10-ha lakes. This type of winter circulation is expected to be ubiquitous throughout the arctic.