Tracking deep-sea internal wave propagation with a differential pressure gauge array
Abstract Temperature is used to trace ocean density variations, and reveals internal waves and turbulent motions in the deep ocean, called ‘internal motions.’ Ambient temperature detected by geophysical differential pressure gauges (DPGs) may provide year-long, complementary observations. Here, we u...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2021-12-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-021-02721-1 |
| _version_ | 1818994460525068288 |
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| author | Chu-Fang Yang Wu-Cheng Chi Hans van Haren Ching-Ren Lin Ban-Yuan Kuo |
| author_facet | Chu-Fang Yang Wu-Cheng Chi Hans van Haren Ching-Ren Lin Ban-Yuan Kuo |
| author_sort | Chu-Fang Yang |
| collection | DOAJ |
| description | Abstract Temperature is used to trace ocean density variations, and reveals internal waves and turbulent motions in the deep ocean, called ‘internal motions.’ Ambient temperature detected by geophysical differential pressure gauges (DPGs) may provide year-long, complementary observations. Here, we use data from four DPGs fixed on the ocean bottom and a high-resolution temperature sensor (T-sensor) 13 m above the seafloor as a square-kilometer array deployed offshore ~ 50 km east of Taiwan facing the open Pacific Ocean to examine the impact of temperature on DPG signals related to internal motions. The DPG signals correlate with T-sensor temperature variations between 0.002 and 0.1 mHz, but have time shifts partially caused by slow thermal conduction from the ambient seafloor to the DPG chamber and partially by internal motion propagation time across the array. Applying beamforming-frequency-wavenumber analysis and linear regression to the arrayed T-sensor and DPG data, we estimate the propagating slowness of the internal motions to be between 0.5 and 7.4 s m−1 from the northwest and northeast quadrants of the array. The thermal relaxation time of the DPGs is within 103–104 s. This work shows that a systematic scan of DPG data at frequencies < 0.1 mHz may help shed light on patterns of internal wave propagation in the deep ocean, especially in multi-scale arrays. |
| first_indexed | 2024-12-20T20:58:18Z |
| format | Article |
| id | doaj.art-e818bd6a2c864951a10d47658c68a429 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-12-20T20:58:18Z |
| publishDate | 2021-12-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-e818bd6a2c864951a10d47658c68a4292022-12-21T19:26:47ZengNature PortfolioScientific Reports2045-23222021-12-011111910.1038/s41598-021-02721-1Tracking deep-sea internal wave propagation with a differential pressure gauge arrayChu-Fang Yang0Wu-Cheng Chi1Hans van Haren2Ching-Ren Lin3Ban-Yuan Kuo4Earth System Science Program, Taiwan International Graduate Program (TIGP), Academia Sinica and National Central UniversityInstitute of Earth Sciences, Academia SinicaRoyal Netherlands Institute for Sea Research (NIOZ)Institute of Earth Sciences, Academia SinicaInstitute of Earth Sciences, Academia SinicaAbstract Temperature is used to trace ocean density variations, and reveals internal waves and turbulent motions in the deep ocean, called ‘internal motions.’ Ambient temperature detected by geophysical differential pressure gauges (DPGs) may provide year-long, complementary observations. Here, we use data from four DPGs fixed on the ocean bottom and a high-resolution temperature sensor (T-sensor) 13 m above the seafloor as a square-kilometer array deployed offshore ~ 50 km east of Taiwan facing the open Pacific Ocean to examine the impact of temperature on DPG signals related to internal motions. The DPG signals correlate with T-sensor temperature variations between 0.002 and 0.1 mHz, but have time shifts partially caused by slow thermal conduction from the ambient seafloor to the DPG chamber and partially by internal motion propagation time across the array. Applying beamforming-frequency-wavenumber analysis and linear regression to the arrayed T-sensor and DPG data, we estimate the propagating slowness of the internal motions to be between 0.5 and 7.4 s m−1 from the northwest and northeast quadrants of the array. The thermal relaxation time of the DPGs is within 103–104 s. This work shows that a systematic scan of DPG data at frequencies < 0.1 mHz may help shed light on patterns of internal wave propagation in the deep ocean, especially in multi-scale arrays.https://doi.org/10.1038/s41598-021-02721-1 |
| spellingShingle | Chu-Fang Yang Wu-Cheng Chi Hans van Haren Ching-Ren Lin Ban-Yuan Kuo Tracking deep-sea internal wave propagation with a differential pressure gauge array Scientific Reports |
| title | Tracking deep-sea internal wave propagation with a differential pressure gauge array |
| title_full | Tracking deep-sea internal wave propagation with a differential pressure gauge array |
| title_fullStr | Tracking deep-sea internal wave propagation with a differential pressure gauge array |
| title_full_unstemmed | Tracking deep-sea internal wave propagation with a differential pressure gauge array |
| title_short | Tracking deep-sea internal wave propagation with a differential pressure gauge array |
| title_sort | tracking deep sea internal wave propagation with a differential pressure gauge array |
| url | https://doi.org/10.1038/s41598-021-02721-1 |
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