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Marine Systems & Ocean Technology

, Volume 10, Issue 1, pp 18–25 | Cite as

Numerical study on the effect of artificial mound settled in the shallow ocean for CO2 fixation

  • Shinichiro Hirabayashi
  • Toru Sato
  • Michimasa Magi
  • Tatsuo Suzuki
Article
  • 1.1k Downloads

Abstract

An artificial mound was settled in the shallow ocean to enhance vertical mixing of nutrients and consequent primary production. It is expected that this technology contributes to the biological fixation of CO2 in the ocean. The turbulent mixing generated by the interaction between tidal currents and the mound was numerically simulated by using large eddy simulation in the cases of spring and half tides. The energy dissipation rate calculated from the numerical simulation shows a large horizontal variation when the tidal speed is large and a clear enhancement by the mound can be seen. The comparison between numerical result and the measurement implies that the location of the measurement was not included in the region of large energy dissipation. The vertical diffusivity was estimated from the numerical result to roughly quantify the vertical diffusive velocity of nutrients, which was enhanced up to 10−6–10−5 m s−1 when the tidal speed is its maximum, while it was 10−7 m s−1 when the effect of the mound is little .

Keywords

Artificial mound Large eddy simulation Energy dissipation rate Vertical diffusivity Biological CO2 fixation Primary production 

Notes

Acknowledgments

The present study was supported in part by the Research Institute of Innovative Technology for the Earth (RITE).

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Copyright information

© The Author(s) 2015

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  • Shinichiro Hirabayashi
    • 1
  • Toru Sato
    • 1
  • Michimasa Magi
    • 2
  • Tatsuo Suzuki
    • 3
  1. 1.Department of Ocean Technology, Policy, and EnvironmentUniversity of TokyoKashiwaJapan
  2. 2.CO2 Storage Research GroupResearch Institute of Technology for the EarthKizugawaJapan
  3. 3.Artificial Sea-Mount InstituteHachioji-shiJapan

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