ESRL/PSD Seminar Series

Abstract

Acoustic tomography of the atmospheric surface layer (ASL) is based on measurements of the travel times of sound propagation between speakers and microphones which constitute a tomography array. Then, the temperature and wind velocity fields inside the tomographic volume or area are reconstructed using different inverse algorithms. Improved knowledge of these fields is important in many practical applications. Tomography has certain advantages in comparison with currently used instrumentation for measurements of the turbulence fields. An array for acoustic tomography of the atmospheric surface layer has recently been built at the Boulder Atmospheric Observatory (BAO). The size of the array is 80 m x 80 m, and it enables the horizontal-slice tomography at the height 8 m above the ground. The instrumentation and principle of operation of the BAO tomography array are explained. Inverse algorithms for reconstruction of the temperature and wind velocity fields from the travel times are reviewed. Results in numerical simulations of the BAO tomography array and reconstruction of the turbulence fields in tomography experiments are presented. Acoustic tomography of the atmosphere can also be performed at other scales, ranging from a size of an ultrasonic anemometer/thermometer to the height of the atmospheric boundary layer and even in the stratosphere and thermosphere.