Measurements of optical turbulence in the lower troposphere by means of arrays of in-situ sensors mounted on stationary and moving platforms

Fast-response and low-noise in-situ measurements of mean values, mean gradients, and turbulent fluctuations of temperature and wind velocity are needed for empirically testing certain hypotheses and theories that form the basis for observing, modeling, and predicting optical turbulence. Examples of such hypotheses and theories are (1) the assumption of fully developed, locally homogeneous and isotropic turbulence, (2) the Obukhov-Corrsin similarity theory, (3) Taylor’s frozen-turbulence hypothesis, (4) the Monin-Obukhov similarity theory, and (5) the assumption of joint lognormality of local turbulence structure parameters and local dissipation rates. Here we present and discuss first results from two field studies: first, collocated ultrasonic anemometer-thermometer (``sonic'') and image-motion measurements from stationary platforms, and second, collocated thin-film and fine-wire turbulence measurements from a fast-moving platform (an automobile traveling at 40 mph).