Notes on the interpretation of ambient noise statistics

Abstract

Interpretation of statements about the character of ambient sea noise, as well as schemes to measure or model noise, are sensitive to the context or underlying view of what is essentially a stochastic process. A framework is proposed to aid in establishing and articulating a nontrivial context or view. For low to mid frequencies, the framework consists of individual types of noise components (background ship noise, wind noise, transient noises) , each with rough estimates of fluctuation rates and statistical distributions for time scales from seconds to years. Estimates of the dependence of fluctuation properties on frequency, beamwidth, etc. , are made whenever possible. Within such a framework, statements about noise properties can be much more readily interpreted , as illustrated through examples derived from ambient noise modeling and measurement problems.