Hydrology of a Small Lake in the Canadian High Arctic

A hydrologic study was made on a small lake (area 0.2 km2) located in continuous permafrost area near Resolute, Northwest Territories, Canada. Depending on the processes that dominate, the hydrology of this lake shows four distinct periods. (1) Snowmelt period occurs when the bulk of the meltwater from the basin collects in the lake because the outflow channel is blocked by snowdrift producing large lake level rises and enhancing initial disintegration of the lake ice cover. (2) Outflow breakup period lasts for several days during which the lake discharges over 75% of its annual flow. (3) Summer period occurs when the lake ice cover rapidly diminishes and evaporation becomes an important source of water loss. In this period, lake evaporation is sustained by rainfall and contribution from the basin slopes. (4) Winter period is characterized by the growth and the maintenance of an ice cover which reaches a maximum thickness of 2.4 m. Over a year, net change in lake storage is small. In terms of the annual water balance, most of the meltwater input discharges as lake outflow while summer rainfall is consumed by evaporation.