Related Experiment Video
Updated: Jun 2, 2026

Visualizing Oceanographic Data to Depict Long-term Changes in Phytoplankton
Published on: July 28, 2023
Low frequency deep ocean ambient noise trend in the Northeast Pacific Ocean
1School of Earth and Ocean Sciences, University of Victoria, Victoria, British Columbia V8P 5C2, Canada. chapman@uvic.ca
Abstract:
Concern about effects of anthropogenic noise on marine life has stimulated new studies to establish present-day ocean noise levels and compare them to noise levels from previous times. This paper reports on the trend in low-frequency (10-400 Hz) ambient noise levels and presents measurements made using a calibrated multi-element volume array at deep ocean sites in the Northeast Pacific from 1978 to 1986. The experiments provided spectral noise levels as well as horizontal and vertical noise directionality. The data presented here provide evidence that the trend derived from 1960s data extended to around 1980, but has since continued at a lower rate.
Related Concept Videos
Deep Sea Microbial Ecology
Marine Microbial Ecology
Intensity and Pressure of Sound Waves
Unlike the time average of a sinusoidal term, which is zero since it is positive and...
Sound as Pressure Waves
The pressure fluctuation depends on the difference in displacements between the successive points in the...
Harmonic Mean
Take the example of the speed of a car, which is the measure of the rate of distance traveled. If the vehicle traverses the same distance back-and-forth, its average speed equals the total distance traveled divided by the total time taken. However, if the car moves with varying speeds, then the arithmetic mean is more skewed...
Influence of Earth's Curvature and Atmospheric Refraction on Leveling

