Mixing below the ice occurs due to density currents generated by heat from direct solar radiation and from meltwater runoff which may differ in density from the lake water due to both temperature and suspended sediment content, depending on its source and flow path. Despite these processes, the effects of wind at the lake surface are highly reduced due to the ice cover, and so vertical mixing of the water column may be incomplete. This may result in anoxic conditions, which has implications for biogeochemical processes within the lake.
Due to differences in density caused by solar radiation and meltwater runoff, intermixing beneath the ice occurs. The source and flow path of this runoff influence its density, which may differ from that of the lake water. As a result, wind's impact on the lake surface is reduced, leading to incomplete vertical mixing of the water column.