An experimental study in micro‐meteorology

Abstract

Abstract A description is presented of the experimental techniques used on four micrometeorological expeditions. The instrumentation was designed to provide half‐hourly mean values of wind speed, temperature and humidity at a number of levels up to 16 metres, and of the vertical fluxes of heat, water vapour, net radiation and sensible heat into the ground. The observational material is to be published separately. Analysis of the observations, all for the unstable case, shows close similarity between the turbulent transfer processes for heat and water vapour over the whole range of stability represented by the measurements. Both are more strongly influenced by instability than the exchange of momentum, the difference in behaviour becoming more marked with increasing instability. It is suggested that the similarity between heat and water vapour transfer is due to a correlation between the temperature and specific humidity of the air which originates at the evaporating surface.