An eddy‐permitting coupled physical‐biological model of the North Atlantic: 1. Sensitivity to advection numerics and mixed layer physics
An eddy‐permitting coupled physical‐biological model of the North Atlantic: 1. Sensitivity to advection numerics and mixed layer physics
复制标题
北大西洋的涡流允许耦合物理生物模型：1. 对平流数值和混合层物理的敏感性
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
V. Garçon
中科院分区：
文献类型：
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作者：
A. Oschlies;V. Garçon
通过将四组分远洋生态系统模式与高分辨率数值环流模式相结合，研究了北大西洋生物初级生产的物理影响。一系列的灵敏度实验证明了上层海洋湍流和平流数值的精确公式的重要作用。与低扩散、高阶、正定平流方案相比，上游平流方案中隐含的不切实际的大扩散率大约是初级产量的两倍。这在赤道上升流区尤其值得关注，在那里，上游平流导致上层海洋硝酸盐浓度显著增加。通过改变生物模型来抵消这种不切实际的大规模隐性扩散的影响，很容易导致对生态系统动力学解释的误解。亚栅格尺度的环流扩散强烈控制着亚热带环流中冬季混合未到达营养线的生物生产。垂直粘度的参数化主要在赤道地区是重要的，在赤道地区摩擦成为动量平衡的重要因素。
Physical influences on biological primary production in the North Atlantic are investigated by coupling a four‐component pelagic ecosystem model with a high‐resolution numerical circulation model. A series of sensitivity experiments demonstrates the important role of an accurate formulation of upper ocean turbulence and advection numerics. The unrealistically large diffusivity implicit in upstream advection approximately doubles primary production when compared with a less diffusive, higher‐order, positive‐definite advection scheme.This is of particular concern in the equatorial upwelling region where upstream advection leads to a considerable increase of upper ocean nitrate concentrations. Counteracting this effect of unrealistically large implicit diffusion by changes in the biological model could easily lead to misconceptions in the interpretation of ecosystem dynamics. Subgrid‐scale diapycnal diffusion strongly controls biological production in the subtropical gyre where winter mixing does not reach the nutricline. The parameterization of vertical viscosity is important mainly in the equatorial region where friction becomes an important agent in the momentum balance.