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Which variable is the cloud liquid water path?

hefei@umich_edu

New Member
I found several variables in the master filed having the meaning of liquid water path(LWP) or can calculate the LWP. However, their values can not match each other. One variable is TGCLDLWP: total grid box averaged cloud liquid water path with unit of kg/m^2. The second is TMCLDLIQ: CLDLIQ colum burden. It has the same meaning as path and the same unit kg/m^2. The third is LWC: grid box averaged liquid water content. According to the longname, the vertical integral of LWC shall be the same as TGCLDLWP. However, what I get is that they have different values. And those two values are different from TMCLDLIQ too. The TMCLDLIQ is unreasonably small. My question is that, what's the difference among those three?What does TMCLDLIQ really mean? Which variable should be the cloud liquid water path? TGCLDLWP or vertical integral of LWC? Thanks a lot! 
 

hannay

Cecile Hannay
AMWG Liaison
Staff member
The liquid water path is TGCLDLWP. This is a total grid box liquid path (it means that it includes cloudy sky and clear sky). This is different from the in-cloud liquid water path that would take into account cloudy sky only (for the in-cloud liquid water you would divide by the grid box cloud fraction). 
 

hefei@umich_edu

New Member
Hi Hannay,Thanks a lot! It's very helpful! I get it right now. The integral of LWC is also equivalent to TGCLDLWP. Thus, they are consistent now.  And your answer makes sense on the difference between TGCLDLWP and TMCLDLIQ. Everything is clear now. Thank you again.Best regards,Fei
 
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