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Updated: Aug 6, 2026
06:06
Sediment Core Extrusion Method at Millimeter Resolution Using a Calibrated, Threaded-rod
Published on: August 17, 2016
Seasonal changes in sediment sound speed profiles
Charles W Holland1, Chad Smith2, Tim Sonnemann1
1Electrical and Computer Engineering, Portland State University, Portland, Oregon 97207, USA.
JASA Express Letters
|July 16, 2026
Summary
Marine sediment sound speed changes seasonally, impacting underwater acoustics. Measurements confirm significant variations in the upper 9 meters, challenging the assumption of constant sound speed profiles.
Area of Science:
- Oceanography
- Acoustics
- Geophysics
Background:
- Marine sediment sound speed profiles are often assumed constant.
- Seasonal temperature changes may affect sediment sound speed.
- Empirical data on these variations are scarce.
Purpose of the Study:
- To measure seasonal variations in marine sediment sound speed profiles.
- To assess the impact of these variations on acoustic propagation.
Main Methods:
- In-situ measurements of sediment sound speed profiles at the New England Patch.
- Data collection during different seasons (late March and early October).
Main Results:
- Significant seasonal differences observed in the upper 9 meters of marine sediment.
- Sound speed gradients varied from 6.0 s⁻¹ in March to 2.6 s⁻¹ in October.
- These variations demonstrably affect acoustic propagation.
Conclusions:
- Marine sediment sound speed is not constant and varies seasonally.
- Seasonal temperature fluctuations are a likely driver of these changes.
- Accurate sound speed profiles are crucial for effective underwater acoustic modeling.
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