南大洋深水形成的可能20世纪放缓
1Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA. Ocean Chemistry Division, Atlantic Oceanographic and Meteorological Laboratory, National Oceanic and Atmospheric Administration, Miami, FL 33149-1026, USA.
Science (New York, N.Y.)
|November 5, 1999
概括
南大洋的深水产量现在低于过去,这可能解释了海洋学数据的差异. 这可能与北大西洋深水形成和冰上漂流的循环有关.
科学领域:
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
- 地质化学 地质化学
背景情况:
- 目前南洋深水产量估计与历史数据之间存在差异.
- 之前的研究表明,在过去的800年里,南大洋的深水通风率显著上升.
研究的目的:
- 为了协调南大洋深水产量的相互矛盾的估计.
- 研究深水产量变化在气候周期中的潜在作用.
主要方法:
- 在南大洋深处对化碳-11 (CFC-11) 库存的分析.
- 将CFC-11数据与物理海洋学和地球化学代理数据进行比较 (例如,碳-14 /碳比,PO4)).
主要成果:
- 目前的CFC-11库存表明,深水生产率约为5 x 10^6 m^3 / s.
- 这一速度低于从碳-14和PO14数据中得出的历史估计 (约为15 x 10^6 m^3/s).
- 建议在20世纪期间大幅减少南大洋深水产量.
结论:
- 观察到的深水产量减少可能解释了当前和历史估计之间的差异.
- 北大西洋和南大洋之间的潜在摇摆机制的深水生产可以驱动1500年的冰上漂浮周期.
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