Unusually loud ambient noise in tidewater glacier fjords: a signal of ice melt

Geophysical Research Letters
By: , and 

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Abstract

In glacierized fjords, the ice-ocean boundary is a physically and biologically dynamic environment that is sensitive to both glacier flow and ocean circulation. Ocean ambient noise offers insight into processes and change at the ice-ocean boundary. Here we characterize fjord ambient noise and show that the average noise levels are louder than nearly all measured natural oceanic environments (significantly louder than sea ice and non-glacierized fjords). Icy Bay, Alaska has an annual average sound pressure level of 120 dB (re 1 μPa) with a broad peak between 1000 and 3000 Hz. Bubble formation in the water column as glacier ice melts is the noise source, with variability driven by fjord circulation patterns. Measurements from two additional fjords, in Alaska and Antarctica, support that this unusually loud ambient noise in Icy Bay is representative of glacierized fjords. These high noise levels likely alter the behavior of marine mammals.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Unusually loud ambient noise in tidewater glacier fjords: a signal of ice melt
Series title Geophysical Research Letters
DOI 10.1002/2014GL062950
Volume 42
Issue 7
Year Published 2015
Language English
Publisher American Geophysical Union
Publisher location Washington, D.C.
Contributing office(s) Alaska Science Center
Description 8 p.
First page 2309
Last page 2316
Country United States
State Alaska
Other Geospatial Icy Bay
Online Only (Y/N) N
Additional Online Files (Y/N) N