Daily evaporation from a small lake in the continental Low Arctic of Canada was examined using three independent experimental methods and a simplified combination model. Mean daily lake evaporation (± variability between methods) was estimated to be 3.2+0.3−0.3 mm d−1 and 2.5+0.6−0.3 mmd−1 over fifty-day periods during two consecutive summers. Based on these results and additional class-A pan data, total thaw-season evaporation estimates of 220 mm to 320 mm were obtained, equivalent to 70% to 100% of annual precipitation. These values are 15 to 70% higher than predicted by standard evaporation maps of Canada. Our results indicate that the Priestley-Taylor model provides a good approximation of the Bowen ratio energy balance model in this setting. As expected, estimates based on mass balance are highly sensitive to uncertainty in measurement of lake inflow and outflow.

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