Near-surface environmentally forced changes in the Ross Ice Shelf observed with ambient seismic noise

Geophysical Research Letters
By: , and 

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Abstract

Continuous seismic observations across the Ross Ice Shelf reveal ubiquitous ambient res- onances at frequencies >5 Hz. These firn-trapped surface wave signals arise through wind and snow bedform interactions coupled with very low velocity structures. Progressive and long-term spectral changes are associated with surface snow redistribution by wind and with a January 2016 regional melt event. Modeling demonstrates high spectral sen- sitivity to near-surface (top several m) elastic parameters. We propose that spectral peak changes arise from surface snow redistribution in wind events, and to velocity drops re- flecting snow lattice weakening near 0◦C for the melt event. Percolation-related refrozen layers and layer thinning may also contribute to long-term spectral changes after the melt event. Single-station observations are inverted for elastic structure for multiple stations across the ice shelf. High-frequency ambient noise seismology presents opportunities for continuous assessment of near surface ice shelf or other firn environments.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Near-surface environmentally forced changes in the Ross Ice Shelf observed with ambient seismic noise
Series title Geophysical Research Letters
DOI 10.1029/2018GL079665
Volume 45
Issue 11
Year Published 2019
Language English
Publisher American Geophysical Union
Contributing office(s) Geologic Hazards Science Center
Description 10 p.
First page 11,187
Last page 11,196
Other Geospatial Ross Ice Shelf