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Organic matter fraction computation

Hi All
I'm new at CLM, and I found some sort of inconsistency in organic matter fraction computation. In CLM 4 Tech note (April 2010) it is defined as om_frac/organic_max (Eq. 6.61, pag. 113), as wellas in lawrence & Slater 2008 (Eq. 1, pag. 148). Which make perfectly sense to me. However, in the code (iniTimeConst.F90) it is defined as: (om_frac/organic_max)**2. Is it a bug, a typo in the report? or maybe I misanderstand the code. Any help is appreciated.
 

slevis

Moderator
Dear Carmelo,Sorry for the confusion. This is a known mistake in the code, and we plan to correct it.Thank you,Sam Levis
 

slevis

Moderator
Dear Carmelo,Sorry for the confusion. This is a known mistake in the code, and we plan to correct it.Thank you,Sam Levis
 

slevis

Moderator
I have new information on this topic:Squaring the ratio tones down the effect of organic matter. We have also introduced another parameterization in the clm (not sure whether in clm4 or 4.5) to further tone down the effect of organic matter when organic matter is little relative to the amount of mineral soil.

If necessary, pls follow-up with Dave Lawrence, who introduced organic matter to the clm.Sam Levis
 

slevis

Moderator
I have new information on this topic:Squaring the ratio tones down the effect of organic matter. We have also introduced another parameterization in the clm (not sure whether in clm4 or 4.5) to further tone down the effect of organic matter when organic matter is little relative to the amount of mineral soil.

If necessary, pls follow-up with Dave Lawrence, who introduced organic matter to the clm.Sam Levis
 
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