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Some parameter issues.

zkk2157

New member
In the file module_cu_kfeta.F, the parameter TIMEC is obtained through automatic calculation. However, I have noticed in many papers that the TIMEC parameter is regarded as an adjustable and optimizable parameter, and I don't understand why. At the same time, in the paper, the critical Richardson number of the water boundary layer in the file module_bl_ysu.F is also regarded as an adjustable variable, but in the original code, it was obtained through automatic calculation. Why is that?
 
TIMEC is convective time scale in the KFETA scheme. Its value depends on many factors like grid size, wind speed, shallow or deep convection, etc. This is why it is calculated. There is no conflict between the paper description " TIMEC parameter is regarded as an adjustable and optimizable parameter' and coding in the model.

As for the critical Richardson number, its value is commonly within the range of 0.2 - 1.0, while 0.25 is a widely used. Its value can be adjusted to better suit a particular environment.

Please refer to the literature for more information regarding these parameters in KFETA cumulus scheme and YSU PBL scheme.
 
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