2022年3月28日
Effect of Climatic Precession on Dansgaard-Oeschger-Like Oscillations
Geophysical Research Letters
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- 巻
- 49
- 号
- 6
- 記述言語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1029/2021GL095695
Using the climate model MIROC4m, we simulate self-sustained oscillations of millennial-scale periodicity in the climate and Atlantic meridional overturning circulation under glacial conditions. We show two cases of extreme climatic precession and examine the mechanism of these oscillations. When the climatic precession corresponds to strong (weak) boreal seasonality, the period of the oscillation is about 1,500 (3,000) years. During the stadial, hot (cool) summer conditions in the Northern Hemisphere contribute to thin (thick) sea ice, which covers the deep convection sites, triggering early (late) abrupt climate change. During the interstadial, as sea ice is thin (thick), cold deep-water forms and cools the subsurface quickly (slowly), which influences the stratification of the North Atlantic Ocean. We show that the oscillations are explained by the internal feedbacks of the atmosphere-sea ice-ocean system, especially subsurface ocean temperature change and salt advection feedback with a positive feedback between the subpolar gyre and deep convection.
- リンク情報
- ID情報
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- DOI : 10.1029/2021GL095695
- ISSN : 0094-8276
- eISSN : 1944-8007
- SCOPUS ID : 85127440633