Temperature correction and usefulness of ocean bottom pressure data from cabled seafloor observatories around Japan for analyses of tsunamis, ocean tides, and low-frequency geophysical phenomenaReport as inadecuate




Temperature correction and usefulness of ocean bottom pressure data from cabled seafloor observatories around Japan for analyses of tsunamis, ocean tides, and low-frequency geophysical phenomena - Download this document for free, or read online. Document in PDF available to download.

Earth, Planets and Space

, Volume 63, Issue 11, pp 1133–1149

First Online: 14 February 2012Received: 23 March 2011Revised: 16 July 2011Accepted: 22 July 2011

Abstract

Ocean bottom pressure OBP data obtained by cabled seafloor observatories deployed around Japan, are known to be significantly affected by temperature changes. This paper examines the relationship between the OBP and temperature records of six OBP gauges in terms of a regression coefficient and lag at a wide range of frequencies. No significant temperature dependency is recognized in secular variations, while substantial increases, at rates of the order of 1 hPa-year, are commonly evident in the OBP records. Strong temperature dependencies are apparent for periods of hours to days, and we correct the OBP data based on the estimated OBP-temperature relationship. At periods longer than days, the temperature corrections work well for extracting geophysical signals for OBP data at a station off Hokkaido KPG2, while other corrected data show insufficient signal-to-noise ratios. At a tsunami frequency, the correction can reduce OBP fluctuations, due to rapid temperature changes, by as much as millimeters, and is especially effective for data at a station off Shikoku MPG2 at which rapid temperature changes most frequently occur. A tidal analysis shows that OBP data at a station off Honshu TM1, and at KPG2, are useful for studies on the long-term variations of tidal constituents.

Key wordsOcean bottom pressure temperature correction tsunami ocean tide oceanic variation  Download fulltext PDF



Author: Daisuke Inazu - Ryota Hino

Source: https://link.springer.com/







Related documents