A generalized complementary principle with physical constraints for land‐surface evaporation

The idea of complementary evaporative fluxes, first advanced by Bouchet (1963), is reformulated as a general polynomial, satisfying boundary conditions based on strictly physical considerations. Experimental evidence supports the validity of the imposed constraints. Earlier complementary relationships are shown to be special cases which satisfy only one of the necessary conditions. The new formulation provides a more rigorous base for the complementary principle.