**3.6 Wind-generated noise**

Noise due to wind is a major contributor of the total ambient noise. Windassociated ambient noise was predicted and analyzed earlier by many researchers. Ambient noise depends on varying wind speeds over the frequency range of 500 Hz to 50 KHz. In this range of frequency, i.e., in KHz, hydrophone is used as an anemometer [1]. Wind speed is considered as the major constituent of ambient noise in the absence of ships and tumid marine life.

Wind noise can be treated as a typical case of random noise. Wind noise in the frequency range of 500 Hz to 20 KHz is called as Knudsen noise, because Knudsen discovered that it correlated very well with wind speed [7].
