Physico-chemical characteristics and origin of hypersaline meromictic Lake Garrow in the Canadian high Arctic

Abstract

The thermal stratification of this lake is mesothermic (heliothermic). Some of the solar energy that penetrates through the 2 m ice cover is stored for a long period of time in the upper level of the monimolimnion, under a greenhouse effect due the water density gradient. The energy transfer (0.06°C m-1) by conduction toward the bottom sediments is very constant from one year to the next and is likely to prevent the presence of permafrost under this water body. In its chemical composition, this meromictic lake is quite comparable to the world's saltiest water bodies and is the first lake, with a salinity greater than sea water to be reported for the Canadian Arctic. Its anoxic monimolimnion is nearly three times (90‰) as salty as normal sea water. This hypersaline water seems to have been derived from isostatic trapped marine waters within the present lacustrine basin as well as from underground during deglaciation of the area. -from Authors