Satellite impact on environmental acoustics

Abstract

The continuous surveillance of atmospheric and oceanic conditions at the sea surface by remote sensing platforms can be exploited to improve acoustic propagation prediction. This improvement is especially important in areas where surface observations are not usually taken or are difficult to take, e.g., in oceanic areas off the main shipping routes or under stormy weather patterns. It has been recently shown that both the climatology of the water mass, as well as the analyzed and/or predicted atmospheric surface fluxes can contain significant errors that are larger than those associated with the remotely sensed signals. The purpose of this paper is to illustrate quantitatively the improvement in the prediction of the acoustic environment and propagation due to remote sensing in such situations by three examples. The first two will use a 1-D mixed-layer model coupled to a range-independent acoustic model to study the impact of joint scatterometer/IR observations on propagation in surface ducts. Both a situation where mechanical stirring due to the wind or where convective stirring due to strong surface cooling is dominant are investigated. The third example will study the improvement in the description of the vertical structure and the horizontal position of an oceanic front, and the corresponding acoustic propagation patterns, due to combined altimeter/IR observations. This study will use a 2-D ocean model coupled to a range-dependent acoustic model.