Icing-dammed proglacial lakes form as a result of water-flow pathway restrictions caused by freezing of winter baseflow. With the majority of glaciers in the eastern Canadian High Arctic that previously terminated at sea level now terminating on land (Vaughan et al., 2013), emerging proglacial environments are becoming more common - resulting in the occurrence of novel terrestrial proglacial water flow regimes. This research addressed the knowledge gap of how a glacier, proglacial environment, and hydrological cycle contribute to delayed water-flow, in the form of a proglacial icing-dammed lake, in the terrestrial proglacial environment. The research was conducted at a unique location on Bylot Island, NU, in the eastern Canadian High Arctic, where icing-dammed proglacial lakes have been observed to form multiple years prior.
In the proglacial environment, icing development has been studied as proxies to infer winter baseflow from upvalley glacial hydrological networks (Hodgkins et al., 2004; Wainstein, 2011). In addition, icing ablation has been studied as it reallocates a portion of winter streamflow to summer streamflow via icing melt (Reedyk et al., 1995). But icing-dammed lake formation in the proglacial environment remains relatively unexplored due to the uniqueness of their formation.
Direct observations, time-lapse photography, lake water level and temperature monitoring, lake bathymetric mapping, and meteorological, electrical conductivity, turbidity, and dye tracing measurements were used to examine the characteristics of an icing-dammed proglacial lake to infer the processes involved for its formation and preservation into the July 2014 summer melt season.
Results suggest that the icing-dammed proglacial lake formation is dependent on: the previous year’s icing state at the end of the melt season; the current icing forming a seal with the surrounding topography to restrict water flow and raise local base water level; and the current year’s melt season flow regime not exceptionally exceeding the current icing’s melt thereby allowing water to pool and form a lake.