of airgun noise. Airguns are used for seismic surveying of
the ocean floors.
the advent of steamships in the 1850s, manmade sounds have
influenced the levels of ambient noise in the oceans. Added
to the background of natural noises, overall levels of sound
in all frequency bands have increased. This increase may potentially
influence both the behavior of marine animals and the ability
of scientists to study acoustic phenomena in the ocean. Studies
of the effect of noise, both manmade and natural, on marine
life are being planned in collaboration with NOAA Fisheries
of man-made environmental sounds are shown below. Natural
environmental sounds include earthquakes, landslides, and
weather (such as rain and waves).