Assessment of the separate effects of baroclinicity and thermal stability in the atmospheric boundary layer over the sea



Pibal soundings taken during the period 1929 to 1936 were analysed to augment our knowledge of boundary layer climatology. Use of the geostrophic departure method enables computation of surface stress and the cross-isobar angle as functions of stability and baroclinicity, the latter being assessed from the upper wind shear. The comparative effects of both terms are discussed and the importance of the often-neglected baroclinicity in explaining the scatter of the computed parameters is stressed. Use of similarity theory enables us to achieve some further order in the data and eventually to estimate the universal functions A and B freed from baroclinic effects.