Meteorol Atmos Phys 85, 21–37 (2004) DOI 10.1007/s00703-003-0031-1 1 Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences, Moscow, Russia 2 Argonne National Laboratory, Argonne, IL, USA Application of SODARs in the study and monitoring of the environment M. A. Kallistratova 1 and R. L. Coulter 2 Received November 13, 2002; January 11, 2003; accepted March 14, 2003 Published online: November 13, 2003 # Springer-Verlag 2003 Summary Application of acoustic sounders (SODARs) to study the atmospheric boundary layer (ABL) began in the early 1970s. During the last two decades the scope of SODARs applications enlarged considerably. The proceedings of eleven symposia of the International Society for Remote Acoustic Sensing of the Atmosphere and Oceans (ISARS) are a unique collection of papers, where all directions of the SODAR use since 1981 are presented. In this paper, a review of SODAR applications to atmospheric research is presented based on materials published in these proceed- ings in the following fields: conditions of microwave and light propagation; regional climatology of the ABL; air pollution meteorology and weather forecast; mesoscale phenomena under stable and unstable stratification; micro- meteorology; peculiarities of the ABL in remote and complex terrain. 1. Introduction Remote acoustic sounding of the atmospheric boundary layer (ABL) has played a major role in understanding and investigating the peculiarities of this layer that is of great importance for the populace at large. SODAR echograms revealed that the ABL was much more complex and multi- farious than previously thought. The intensive use of acoustic sounding to study the ABL started almost simultaneously with the appearance of the first SODARs in the early 1970s, and continues unabated to this day. Achievements in development of SODAR techniques during last two decades (see the companion paper in this issue, Coulter and Kallistratova, 2003) and growth in commercial SODARs contributed to SODAR expansion to new areas of atmospheric research. SODARs have apparently raised their status to that of a ‘‘respectable’’ operational technique. Their applications cover a wide range of different fields including: investigation of conditions of microwave and light propagation; regional clima- tology of the ABL; air pollution meteorology and weather forecasting; and study of mesoscale flows and turbulence structure under stable and unstable stratification (low-level jet flows, wave motions, elevated layers, convective thermals, etc.). In many cases SODAR was used in conjunction with other instruments, which enhanced the understanding of atmospheric processes. SODAR measurements in complex and remote terrain, such as the Antarctic and Arctic, mountains, coastal sites and sea, urban and desert areas pro- vided new information on flows and turbulence several hundred of meters above the surface in such regions, where the use of other mea- surement techniques is difficult. The papers on SODAR applications are dispersed among many atmospheric physics and meteorology journals.