Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge
Seismic monitoring of the cryosphere is mostly done with land seismometers on the surface of ice masses. Seismic monitoring beneath sea ice at the bottom of ice-covered oceans has hardly been attempted, because ocean bottom seismometers (OBS) are difficult to recover in perennial sea ice. As a resul...
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ftawi:oai:epic.awi.de:54934 2023-05-15T14:27:44+02:00 Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge Schlindwein, Vera Kirk, Henning Hiller, Marc S. Scholz, John-Robert Schmidt-Aursch, Mechita C. 2021 https://epic.awi.de/id/eprint/54934/ https://hdl.handle.net/10013/epic.eff01915-fdab-4ae5-83b3-d4712bb8a160 unknown Schlindwein, V. orcid:0000-0001-5570-2753 , Kirk, H. , Hiller, M. S. , Scholz, J. R. and Schmidt-Aursch, M. C. orcid:0000-0002-2393-4514 (2021) Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge , 37th General Assembly of the European Seismological Commission, Corfu, Greece, 19 September 2021 - 24 September 2021 . hdl:10013/epic.eff01915-fdab-4ae5-83b3-d4712bb8a160 EPIC337th General Assembly of the European Seismological Commission, Corfu, Greece, 2021-09-19-2021-09-24 Conference notRev 2021 ftawi 2021-12-24T15:46:35Z Seismic monitoring of the cryosphere is mostly done with land seismometers on the surface of ice masses. Seismic monitoring beneath sea ice at the bottom of ice-covered oceans has hardly been attempted, because ocean bottom seismometers (OBS) are difficult to recover in perennial sea ice. As a result, for example the tectonic activity of the Arctic mid-ocean ridge system is poorly known. Recently, ambient seismic noise in long-term seismic records proved a useful tool to monitor the state of the sea ice cover. From September 2018 - September 2019, we deployed a trial network of 4 broadband OBS in Arctic sea ice. OBS were positioned at distances of 10 km at a water depth of 4 km on eastern Gakkel Ridge. Station noise levels from power spectral density analysis are considerably lower for sub-ice stations than for OBS in the Greenland Sea and are comparable to those of Arctic land stations. The network was designed to record local earthquakes along Gakkel Ridge, but it also yielded valuable data on the sub-ice ambient seismic noise in the Arctic Ocean. Spectrograms covering the entire deployment reveal pronounced seasonality in different frequency bands: Above 5 Hz, noise levels increase when sea ice cover is present. In addition, anthropogenic noise is prominently seen. The secondary microseismic noise peak has two clearly separable components with opposite seasonal evolution. Microseisms at 3-10 s periods relate to swell events outside the Arctic Ocean with a higher incidence of such events during winter time. In contrast, secondary microseisms originating in the Arctic Ocean peak in September during the annual sea ice minimum. Their periods increase from 0.5 s to 5 s as the fetch area for wave evolution increases from June to September. Conference Object Arctic Arctic Arctic Ocean Greenland Greenland Sea Sea ice Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Arctic Arctic Ocean Gakkel Ridge ENVELOPE(90.000,90.000,87.000,87.000) Greenland |
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Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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ftawi |
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description |
Seismic monitoring of the cryosphere is mostly done with land seismometers on the surface of ice masses. Seismic monitoring beneath sea ice at the bottom of ice-covered oceans has hardly been attempted, because ocean bottom seismometers (OBS) are difficult to recover in perennial sea ice. As a result, for example the tectonic activity of the Arctic mid-ocean ridge system is poorly known. Recently, ambient seismic noise in long-term seismic records proved a useful tool to monitor the state of the sea ice cover. From September 2018 - September 2019, we deployed a trial network of 4 broadband OBS in Arctic sea ice. OBS were positioned at distances of 10 km at a water depth of 4 km on eastern Gakkel Ridge. Station noise levels from power spectral density analysis are considerably lower for sub-ice stations than for OBS in the Greenland Sea and are comparable to those of Arctic land stations. The network was designed to record local earthquakes along Gakkel Ridge, but it also yielded valuable data on the sub-ice ambient seismic noise in the Arctic Ocean. Spectrograms covering the entire deployment reveal pronounced seasonality in different frequency bands: Above 5 Hz, noise levels increase when sea ice cover is present. In addition, anthropogenic noise is prominently seen. The secondary microseismic noise peak has two clearly separable components with opposite seasonal evolution. Microseisms at 3-10 s periods relate to swell events outside the Arctic Ocean with a higher incidence of such events during winter time. In contrast, secondary microseisms originating in the Arctic Ocean peak in September during the annual sea ice minimum. Their periods increase from 0.5 s to 5 s as the fetch area for wave evolution increases from June to September. |
format |
Conference Object |
author |
Schlindwein, Vera Kirk, Henning Hiller, Marc S. Scholz, John-Robert Schmidt-Aursch, Mechita C. |
spellingShingle |
Schlindwein, Vera Kirk, Henning Hiller, Marc S. Scholz, John-Robert Schmidt-Aursch, Mechita C. Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge |
author_facet |
Schlindwein, Vera Kirk, Henning Hiller, Marc S. Scholz, John-Robert Schmidt-Aursch, Mechita C. |
author_sort |
Schlindwein, Vera |
title |
Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge |
title_short |
Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge |
title_full |
Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge |
title_fullStr |
Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge |
title_full_unstemmed |
Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge |
title_sort |
ambient seismic noise under the sea-ice of the arctic ocean: first results from a pilot experiment with ocean bottom seismometers at eastern gakkel ridge |
publishDate |
2021 |
url |
https://epic.awi.de/id/eprint/54934/ https://hdl.handle.net/10013/epic.eff01915-fdab-4ae5-83b3-d4712bb8a160 |
long_lat |
ENVELOPE(90.000,90.000,87.000,87.000) |
geographic |
Arctic Arctic Ocean Gakkel Ridge Greenland |
geographic_facet |
Arctic Arctic Ocean Gakkel Ridge Greenland |
genre |
Arctic Arctic Arctic Ocean Greenland Greenland Sea Sea ice |
genre_facet |
Arctic Arctic Arctic Ocean Greenland Greenland Sea Sea ice |
op_source |
EPIC337th General Assembly of the European Seismological Commission, Corfu, Greece, 2021-09-19-2021-09-24 |
op_relation |
Schlindwein, V. orcid:0000-0001-5570-2753 , Kirk, H. , Hiller, M. S. , Scholz, J. R. and Schmidt-Aursch, M. C. orcid:0000-0002-2393-4514 (2021) Ambient seismic noise under the sea-ice of the Arctic Ocean: First results from a pilot experiment with Ocean Bottom Seismometers at eastern Gakkel Ridge , 37th General Assembly of the European Seismological Commission, Corfu, Greece, 19 September 2021 - 24 September 2021 . hdl:10013/epic.eff01915-fdab-4ae5-83b3-d4712bb8a160 |
_version_ |
1766301609027960832 |