Estimation of surface stress and heat flux from profile data

The problem of estimating shearing stress from the wind profile in the lowest layers is discussed from the operational viewpoint. It is concluded that wind‐profile data alone may never in practice be sufficient, even though a universal profile with the stress as a separable parameter may be established by future research. On the other hand the determination of both stress and heat flux, with adequate accuracy, may be possible from single values of temperature gradient and wind gradient observed simultaneously. A difficulty common to all indirect methods lies in interpreting the sampling variations.