Describe 'attenuation' in the context of acoustic signals.

Attenuation refers specifically to the reduction in the strength of acoustic signals as they propagate through a medium, such as water in the marine environment. As sound waves travel, they lose energy due to various factors, including scattering, absorption, and geometric spreading. This gradual decrease in intensity means that the further the sound travels, the weaker it becomes, which is a crucial consideration in underwater acoustics, particularly for applications such as sonar and marine communications.

In contrast, the other choices suggest different phenomena: amplification implies an increase in signal strength rather than a decrease; complete absorption relates only to how sound energy is entirely absorbed by a surface, which doesn't encompass the broader concept of attenuation; and reflection deals with how sound waves bounce off surfaces, which also does not define attenuation. Understanding attenuation is vital for interpreting acoustic data accurately and for the effective use of sound in oceanographic studies.