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This post was from a previous version of the WRF&MPAS-A Support Forum. New replies have been disabled and if you have follow up questions related to this post, then please start a new thread from the forum home page.

Hello professor, I found you said, AKHS is proportional to USTAR.
I want to output surface exchange coefficient for heat Ck and momentum Cd at 10m.
I found that YSU, MYNN2, MYNN3 PBL scheme, using same sfclay scheme Revised MM5 surface layer scheme, they can directly output "CD" and "CK" at 10m and "MOL" (T*).
But MYJ with myjsfclay and QNSE PBL scheme with qnsesfclay do not output Cd and Ck and T*. These two schemes only output AKMS and AKHS.
In Registry.EM_COMMON file, as follows:
state real CD ij misc 1 - r "CD" "DRAG COEFF AT 10m" ""
state real CK ij misc 1 - r "CK" "ENTHALPY EXCHANGE COEFF AT 10 m" ""
state real AKHS ij misc 1 - r "AKHS" "SFC EXCH COEFF FOR HEAT" "m s-1"
state real AKMS ij misc 1 - r "AKMS" "SFC EXCH COEFF FOR MOMENTUM" "m s-1"
HOW to use AKMS and AKHS to obtain Ck and Cd at 10m for MYJ and QNSE scheme? please give me some help. Thank you so much.

Here, I know "CD" and "CK" means COEFF AT 10m, and they do not have unit. But which height level are "AKHS" and "AKMS" at? And I note that the unit of "AKHS" and "AKMS" is "m s-1"? what is that mean? "AKHS" and "AKMS" stand wind speed? I can not understand it, please give me some help.
AND Due to only sfclay1 can output "CD" and "CK", but sfclay2 and sfclay4 do not output "CD" and "CK". sfclay2 and sfclay4 can output "AKMS" and "AKHS", but the value is too large, maybe 100 times for "CD" and "CK" in sfclay1. So how can I get "CD" and "CK" at 10m for sfclay2 and sfclay4? please give me some help. Thank you so much.
This post has been split from the other since it's best to start a new topic. Someone will respond to your inquiry soon.