scope:

Introduction

A description of the relation between emission and immission is only possible on the basis of information about the horizontal and vertical dispersion conditions in the atmosphere, which depend on meteorological parameters. In addition to wind, these include factors influencing turbulence (such as solar radiation, cloud cover, stability of atmospheric layers, condition and type of the surface of the earth), and precipitation. Wind has a substantial effect on the dispersion and transport of gases and particles, on their dwell time, their mixing, and changes in their concentrations. Wind speed and direction must therefore be measured continuously.

This guideline describes the in-situ measurement of wind speed using rotating, thermal, ultrasonic, and laser anemometers, the measurement of wind direction using wind vanes, and further methods for the determination of the wind vector. Remote sensing of the wind vector by Doppler SODAR, Doppler LIDAR, etc., is dealt with in VDI 3786 Part 11 and Part 14 [1; 2] . In addition to the measurement methods, this guideline describes the installation of the measuring instruments, quality assurance, the recording and evaluation ofthe measured data.

The evaluation of the measured data shall be considered when planning measurements so as to ensure comparability of the results. In that sense, the methodology to be selected for data acquisition, data transmission, and data evaluation is largely predetermined by the measurement task.

This guideline can but present a framework. For particular problems and special investigations, meteorological expert counsel is required. This is particularly true in the field of research.