IMPROVED AERODYNAMIC EVAPORATION TECHNIQUE FOR LARGE LAKES WITH APPLICATION TO THE INTERNATIONAL FIELD YEAR FOR THE GREAT-LAKES

An improved bulk transfer technique was developed for large‐lake evaporation based upon recent boundary layer research near the air‐water interface. A variable bulk transfer coefficient, dependent upon atmospheric stability, is given as a function of the nondimensional wind speed gradient, the potential temperature gradient, and the Monin‐Obukhov length. The technique, which requires the same data as the simplified mass transfer equation, can be readily applied to large lakes throughout the world. This technique has been applied to the Lake Ontario data set collected during the International Field Year for the Great Lakes. The inclusion of stability increases calculated evaporation during the unstable high‐evaporation months and decreases calculated condensation during the stable late spring months to more realistic levels. Comparisons between the Lake Hefner mass transfer equation and the technique recommended here indicate that the mass transfer equation may overestimate Lake Ontario evaporation by approximately 20%. This paper is not subject to U.S. copyright. Published in 1979 by the American Geophysical Union.