When the wind howls, what exactly is making the noise?
• When the wind blows over, through or round an object, it can produce whispers, whistles or howls, depending on the shape of the object and the wind speed. The interaction creates turbulence in the air in the form of eddies, or vortices. As a vortex forms, there is a change in air pressure within it and this propagates a pressure wave. A series of vortices, produced at a certain frequency, will make a sound of the same frequency. As the wind speed rises, so does the rate of vortex…
