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question about ysu pbl scheme

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Hello professor, I want to change the magnitude of eddy diffusivity (Km) and boundary layer height (PBLH) in YSU PBL scheme. The code is module_bl_ysu.F. And Km is exch_m in this code, PBLH is hpbl in this code. Could you please give me some help? Thank you so much.
Both of these two variables are diagnostic variables calculated in PBL scheme at each time time.
If you change their magnitude, then the physics behind to support their calculation will be unreasonable and unrealistic.
Thank you for your reply. I got it and I only want to do some test simulation with different magnitude of Km or PBLH. And (1) make Km mutiply 1.5 or 0.5, change Km to 1.5Km or 0.5Km; (2) make PBLH mutiply 1.5 or 0.5, change PBLH to 1.5PBLH or 0.5PBLH. in the code module_bl_ysu.F, Km is EXCH_M, and PBLH is hpbl. Could you please give me some help to change it? Thank you.

In the figure of formula, Km is diffusivity, and h is PBL height. How to change it in the code?


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Please look at the code module_bl_ysu.F, in which you will find the subroutine "ysu2d". PBLH, EXCH_M and EXCH_H are calculated in this subroutine.
I suppose you can change their values in this subroutine.