Experimental Methods for Understanding Turbulence in the Lower Atmosphere

Abstract

Study of the atmospheric boundary layer is of critical importance since a myriad of processes in this region are intrinsically linked to atmospheric transport and mixing, from dispersion of aerosol particles or pollen plumes, to modeling of weather and climate, and even to predator-prey tracking. On the larger scale, accurately representing land-atmospheric exchange processes remains a challenge in numerical weather predictions due to heterogeneities in topography, land cover, and stability. To address some of the difficulties encountered in probing the atmospheric surface layer, a unique and economically scalable field measurement platform was designed using nano-scale sensors and deployed in Utah's West Desert. Streamwise velocity and temperature data in the first meter above ground were captured with unprecedented spatial resolution, which allowed for an examination of their clustering properties under various atmospheric stability regimes. On a smaller scale, the atmospheric flow environment also dictates the mate- and/or host-seeking behavior of numerous animals. For one, female mosquitoes locate potential hosts by tracking carbon dioxide, volatile skin emanations, humidity, and thermal cues, each of which acts as a passive scalar distributed by local flow conditions. Thus, a better understanding of how the female mosquito responds to cues under various flow settings will facilitate strategies that seek to disrupt its host-seeking behavior and curtail the spread of mosquito-borne diseases. To this end, a low-cost active grid with individually controlled winglets was designed and constructed to mimic features of atmospheric flow in laboratory settings.