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MYNN TKE budget

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New member
I'm using the em_seabreeze2d_x case with MYNN level3 in WRF 4.2. I noticed the TKE budget terms (QBUOY. QDISS etc) had magnitudes that were way too big. For example, QBUOY near surface was way larger than 1 after being nominalized by w_star^3/Zi. I went through the code and found the QBUOY was multiplied by delt, which I don't quite understand the reason for. After I removed the *delt part in the code, the magnitude seemed to be normal. I wonder if this is the correct way to do it? If not, can you briefly explain the reason why the code was that way?

Thanks, and best,
Would you please take a look at this paper:
Nakanishi, M., and H. Niino, 2009: Development of an improved turbulence closure model for the atmospheric boundary layer. J. Meteor. Soc. Japan, 87, 895–912. doi:10.2151/jmsj.87.895
I remember this paper describes the MYNN PBL and many details in the codes can be found here.