The Nocturnal Boundary Layer: A Case Study Compared with Model Calculations

Abstract

A case study of nocturnal boundary-layer development is presented. The data include observations of turbulence and of profiles of wind and temperature. The measurements were done along a 200 m high meteorological mast. The observations are interpreted in terms of the results of a one-dimensional boundary-layer model. The model is derived from the full set of equations governing the evolution of the nocturnal boundary layer by neglecting advection. The validity of this approximation is discussed. From a comparison of observations and calculated results it follows that the influence of advection is important especially in the upper part of the boundary layer. Nevertheless, we find that important characteristics of the nocturnal boundary layer such as its height can be reasonably well simulated by a one-dimensional model.