Evaluating carbon sequestration efficiency in an ocean circulation model by adjoint sensitivity analysis
Evaluating carbon sequestration efficiency in an ocean circulation model by adjoint sensitivity analysis
复制标题
通过伴随敏感性分析评估海洋环流模型中的碳封存效率
DOI：
10.1029/2002jc001598
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发表时间：
2004
影响因子：
--
通讯作者：
J. Marshall
中科院分区：
文献类型：
--
作者：
C. Hill;V. Bugnion;M. Follows;J. Marshall
[1]我们演示了应用伴随方法开发三维地图的碳封存效率和平均停留时间在海洋环流模式。与扰动灵敏度实验相比，伴随方法提供了一种计算有效的方式来表征完整的全球模型域的封存效率和停留时间的时间和空间变化。封存效率（在连续点源注入的碳在经过一段时间后仍留在海洋中的百分比），对于主温跃层底部（-900米）的注入，相对于北太平洋，北大西洋盆地（拉布拉多海的深对流区域除外）最初最低。然而，对于一个世纪或更长时间的注入期，该模型表明，太平洋注入地点一般是一个恒定速率注入源的效率较低。平均停留时间（定义为从特定点源脉冲注入的碳保留在海洋中的平均时间）也进行了评估和映射。这一措施还表明，大西洋封存从长远来看更有效。我们的计算得出了对流混合的双重作用，既暴露浅封存源的大气，也在亚极地大西洋和拉布拉多海，从浅注入源到深循环远离大气的碳。索引术语：1635全球变化：海洋（4203）; 4532海洋学身体状况：一般流通; 4806海洋学生物和化学：碳循环; 3210数学地球物理学：建模;关键词：伴随，海洋环流，碳封存
[1] We demonstrate the application of the adjoint method to develop three-dimensional maps of carbon sequestration efficiency and mean residence time in an ocean general circulation model. In contrast to perturbation sensitivity experiments, the adjoint approach provides a computationally efficient way to characterize both temporal and spatial variations of sequestration efficiency and residence time for a complete global model domain. Sequestration efficiency (the percentage of carbon injected at a continuous point source that remains in the ocean after an elapsed time), for injections at the base of the main thermocline (� 900 m), is initially lowest in the North Atlantic basin (except for regions of deep convection in the Labrador Sea) relative to the North Pacific. For injection periods of the order of a century or more, however, the model suggests that Pacific injection sites are generally less efficient for a constant rate injection source. The mean residence time (defined as the average period that impulsively injected carbon from a particular point source remains within the ocean) is also evaluated and mapped. This measure also suggests that Atlantic sequestration is more efficient in the long term. Our calculations draw out the dual role of convective mixing, both exposing shallow sequestration sources to the atmosphere and also, in the subpolar Atlantic and Labrador Sea, feeding carbon from shallow injection sources into the deep circulation away from the atmosphere. INDEX TERMS: 1635 Global Change: Oceans (4203); 4532 Oceanography: Physical: General circulation; 4806 Oceanography: Biological and Chemical: Carbon cycling; 3210 Mathematical Geophysics: Modeling; KEYWORDS: adjoint, ocean circulation, carbon sequestration