A dynamically based transport parameterization for one-dimensional photochemical models
A dynamically based transport parameterization for one-dimensional photochemical models
复制标题
一维光化学模型的动态传输参数化
DOI：
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发表时间：
1986
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通讯作者：
J. Holton
中科院分区：
文献类型：
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作者：
J. Holton
平流层中的净垂直示踪剂通量主要是由于全球尺度平均纬向环流的平流，而不是湍流涡旋的扩散。使用一个简单的模型，这种流通，它示出的净通量可以近似的通量梯度关系，其中垂直的“涡输运”系数是成正比的非绝热加热速率的平方和成反比的速率，在该速率下，水平涡混合和化学阻尼破坏的示踪剂梯度。因此，对于具有不同化学寿命的示踪剂，迁移系数将不同。为各种源气体（CH 4，N2O，CF2Cl2和CFCl3）计算的配置文件显示，这种参数化提供了一个改进传统的配方，利用一个单一的传输系数为所有物种。
The net vertical tracer flux in the stratosphere is due primarily to advection by the global-scale mean meridional circulation, not to diffusion by turbulent eddies. Using a simple model of this circulation, it is shown that the net flux can be approximated by a flux-gradient relationship in which the vertical “eddy transport” coefficient is proportional to the square of the diabatic heating rate and inversely proportional to the rate at which meridional tracer gradients are destroyed by horizontal eddy mixing and chemical damping. Thus the transport coefficient will differ for tracers with differing chemical lifetimes. Profiles computed for various source gases (CH4, N2O, CF2Cl2, and CFCl3) show that this parameterization provides an improvement over conventional formulations that utilize a single transport coefficient for all species.