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How is surfdata's variable monthly_lai obtained?

xiaom

X M
New Member
Hi, I am using the surfdata file 'surfdata_1.9x2.5_16pfts_Irrig_CMIP6_simyr2000_c170824.nc' and have taken the weighted average of the 'monthly_lai' variable from the model’s default surfdata to compare it with GIMMS LAI data. In the CLM5 technical manual, I saw that the LAI values in the surfdata are based on the average MODIS LAI data from 2001-2003. Therefore, I compared the average LAI values for the corresponding years from GIMMS with the weighted average of 'monthly_lai' in the surfdata. The GIMMS data values were about 0.24 higher than the SURFDATA values.

I would like to know the following questions:

1. Is the 'monthly_lai' value in the surfdata I am using based on the average of 2001-2003? If not, how were these LAI values obtained?

2. For the various types of surfdata, were the LAI values all derived using the method mentioned in the CLM5 technical manual, which uses the 2001-2003 MODIS LAI data?

3.Is it rational to compare the average GIMMS LAI data with the weighted average of the monthly_lai data from surfdata?

Looking forward to your reply, thank you!
 

oleson

Keith Oleson
CSEG and Liaisons
Staff member
1. Yes
2. Yes
3. I don't know anything about GIMMS so I can't see whether such a comparison is reasonable.
 
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