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Counter intuitive behavior for MYJ vertical diffusion coefficients

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New member
Dear all,

I have a question regarding the results i am obtaining when changing the vertical diffusion coefficients in the MYJ PBL scheme. By changing the AKM and AKH coefficients in the "SUBROUTINE DIFCOF", and by changing I mean multiplying the variables by 0.5 or 2, I am getting counter intutitve results for wind intensities. When I reduce the AKM and AKH coefficients by multiplying them by half, I expected wind intensities to increase since I am basically reducing the turbulence mixing by half. However, wind intensities got increased? Likewise, once I increased the AKM and AKH by a factor of 2, I expected a decrease in the wind intensity values, however they increased?

Please advise, any kind of help is appriciated. Thanks!