The Deep Ocean Buoyancy Budget and Its Temporal Variability
The Deep Ocean Buoyancy Budget and Its Temporal Variability
复制标题
深海浮力预算及其时间变化
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
A. Klocker
中科院分区：
文献类型：
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作者：
J. Palter;S. Griffies;B. Samuels;E. Galbraith;A. Gnanadesikan;A. Klocker
尽管海洋混合的速度很慢，但观测和模拟研究表明，浮力在令人惊讶的短年际到十年的时间尺度上重新分配到海洋的所有深度。人们对这种再分配的机制仍然知之甚少。这项工作使用一个地球系统模型来评估全球稳态海洋浮力（和相关的空间海平面）预算，其年际变化，以及其瞬态响应CO2增加一倍超过70年，重点是深海。在稳定状态下，深海垂直对流扩散平衡的简单观点在低至中纬度地区成立。在高纬度地区，这种平衡取决于无数的附加项，即中尺度和亚中尺度平流、对流和边缘海的溢流，以及与非线性状态方程有关的项。这些高纬度过程迅速地将表层浮力强迫的异常传递到局部的深海;深海、高纬度的变化导致了海洋表层浮力强迫的异常。
AbstractDespite slow rates of ocean mixing, observational and modeling studies suggest that buoyancy is redistributed to all depths of the ocean on surprisingly short interannual to decadal time scales. The mechanisms responsible for this redistribution remain poorly understood. This work uses an Earth system model to evaluate the global steady-state ocean buoyancy (and related steric sea level) budget, its interannual variability, and its transient response to a doubling of CO2 over 70 years, with a focus on the deep ocean. At steady state, the simple view of vertical advective–diffusive balance for the deep ocean holds at low to midlatitudes. At higher latitudes, the balance depends on a myriad of additional terms, namely mesoscale and submesoscale advection, convection and overflows from marginal seas, and terms related to the nonlinear equation of state. These high-latitude processes rapidly communicate anomalies in surface buoyancy forcing to the deep ocean locally; the deep, high-latitude changes th...