Effect of Rain upon Underwater Noise Levels

Abstract
Measurements during two heavy rainstorms through an off‐shore calibrated hydrophone system showed an increase of up to 25 db in the 20 to 20 000 cps band pressure level as compared to the ambient level before and after. During the period of heaviest rainfall the pressure spectrum level was approximately constant at −23 db //1 dyne/cm 2 from below 1 kc to above 10 kc, and apparently extends to beyond 40 kc. The pressure spectrum level of the ambient noise can be calculated from the wind force and from a reasonable estimate of the intensity of rainfall.