An experimentalist's overview of wind reduction systems in infrasound measurements

Abstract

The largest limiting factor in infrasound measurements is wind noise. This noise is caused by pressure fluctuations generated by turbulent flow passing over an acoustic sensor. The size scales of these turbulent fluctuations vary from centimeters to tens of meters and larger. This, coupled with the wide variety of possible measurements, means that there is no single best solution to this problem. Instead, wind reduction systems should be tailored to best fit the intended measurement. In this talk, I will give a brief review of wind noise from an experimentalist’s point of view, and will discuss some of the physical principles to consider when choosing a wind noise reduction system. This will include spherical and domed wind screens, porous hoses and pipe arrays, probe microphones, and terrain and foliage considerations.