THE EFFECT OF WEATHER VARIABILITY ON THE ENERGY-BALANCE OF A LAKE IN THE HUDSON-BAY LOWLANDS, CANADA

Hourly summertime estimates of evaporation, from a small tundra lake near Churchill, Manitoba, are compared to equilibrium evaporation estimates of the Penman model. For the entire measurement period α=1.35. For individual days α ranges from 1.0 to 2.0 and for individual hours from 1.0 to 4.0. Local advection is primarily responsible for the large fluxes of latent heat. The latent heat flux exceeds available radiant energy over the the summer, with temperature inversions occurring over the lake on the majority of days. The advective enhancement of lake evaporation responds to daily weather variations. -from Authors